Auto merge of #72627 - Dylan-DPC:rollup-bavnoq5, r=Dylan-DPC

Rollup of 6 pull requests

Successful merges:

 - #72270 (add a lint against references to packed fields)
 - #72294 (JS cleanup)
 - #72342 (Warn about unused crate deps)
 - #72401 (Use correct function for detecting `const fn` in unsafety checking)
 - #72581 (Allow unlabeled breaks from desugared `?` in labeled blocks)
 - #72592 (Update books)

Failed merges:

r? @ghost

src/test/ui/issues/issue-27060-rpass.rs

@@ -7,19 +7,10 @@ pub struct Good {
     aligned: [u8; 32],
 }
 
-#[repr(packed)]
-pub struct JustArray {
-    array: [u32]
-}
-
 // kill this test when that turns to a hard error
 #[allow(safe_packed_borrows)]
 fn main() {
-    let good = Good {
-        data: &0,
-        data2: [&0, &0],
-        aligned: [0; 32]
-    };
+    let good = Good { data: &0, data2: [&0, &0], aligned: [0; 32] };
 
     unsafe {
         let _ = &good.data; // ok

src/test/ui/issues/issue-27060.rs

@@ -5,11 +5,6 @@ pub struct Good {
     aligned: [u8; 32],
 }
 
-#[repr(packed)]
-pub struct JustArray {
-    array: [u32]
-}
-
 #[deny(safe_packed_borrows)]
 fn main() {
     let good = Good {

src/test/ui/issues/issue-27060.stderr

@@ -1,11 +1,11 @@
 error: borrow of packed field is unsafe and requires unsafe function or block (error E0133)
-  --> $DIR/issue-27060.rs:26:13
+  --> $DIR/issue-27060.rs:21:13
    |
 LL |     let _ = &good.data;
    |             ^^^^^^^^^^
    |
 note: the lint level is defined here
-  --> $DIR/issue-27060.rs:13:8
+  --> $DIR/issue-27060.rs:8:8
    |
 LL | #[deny(safe_packed_borrows)]
    |        ^^^^^^^^^^^^^^^^^^^
@@ -14,7 +14,7 @@ LL | #[deny(safe_packed_borrows)]
    = note: fields of packed structs might be misaligned: dereferencing a misaligned pointer or even just creating a misaligned reference is undefined behavior
 
 error: borrow of packed field is unsafe and requires unsafe function or block (error E0133)
-  --> $DIR/issue-27060.rs:28:13
+  --> $DIR/issue-27060.rs:23:13
    |
 LL |     let _ = &good.data2[0];
    |             ^^^^^^^^^^^^^^

src/test/ui/label/label_break_value_desugared_break.rs

@@ -0,0 +1,12 @@
+// compile-flags: --edition 2018
+#![feature(label_break_value, try_blocks)]
+
+// run-pass
+fn main() {
+    let _: Result<(), ()> = try {
+        'foo: {
+            Err(())?;
+            break 'foo;
+        }
+    };
+}

src/test/ui/lint/unaligned_references.rs

@@ -0,0 +1,22 @@
+#![deny(unaligned_references)]
+
+#[repr(packed)]
+pub struct Good {
+    data: &'static u32,
+    data2: [&'static u32; 2],
+    aligned: [u8; 32],
+}
+
+fn main() {
+    unsafe {
+        let good = Good { data: &0, data2: [&0, &0], aligned: [0; 32] };
+
+        let _ = &good.data; //~ ERROR reference to packed field
+        let _ = &good.data as *const _; //~ ERROR reference to packed field
+        let _: *const _ = &good.data; //~ ERROR reference to packed field
+        let _ = &good.data2[0]; //~ ERROR reference to packed field
+        let _ = &*good.data; // ok, behind a pointer
+        let _ = &good.aligned; // ok, has align 1
+        let _ = &good.aligned[2]; // ok, has align 1
+    }
+}

src/test/ui/lint/unaligned_references.stderr

@@ -0,0 +1,39 @@
+error: reference to packed field is unaligned
+  --> $DIR/unaligned_references.rs:14:17
+   |
+LL |         let _ = &good.data;
+   |                 ^^^^^^^^^^
+   |
+note: the lint level is defined here
+  --> $DIR/unaligned_references.rs:1:9
+   |
+LL | #![deny(unaligned_references)]
+   |         ^^^^^^^^^^^^^^^^^^^^
+   = note: fields of packed structs are not properly aligned, and creating a misaligned reference is undefined behavior (even if that reference is never dereferenced)
+
+error: reference to packed field is unaligned
+  --> $DIR/unaligned_references.rs:15:17
+   |
+LL |         let _ = &good.data as *const _;
+   |                 ^^^^^^^^^^
+   |
+   = note: fields of packed structs are not properly aligned, and creating a misaligned reference is undefined behavior (even if that reference is never dereferenced)
+
+error: reference to packed field is unaligned
+  --> $DIR/unaligned_references.rs:16:27
+   |
+LL |         let _: *const _ = &good.data;
+   |                           ^^^^^^^^^^
+   |
+   = note: fields of packed structs are not properly aligned, and creating a misaligned reference is undefined behavior (even if that reference is never dereferenced)
+
+error: reference to packed field is unaligned
+  --> $DIR/unaligned_references.rs:17:17
+   |
+LL |         let _ = &good.data2[0];
+   |                 ^^^^^^^^^^^^^^
+   |
+   = note: fields of packed structs are not properly aligned, and creating a misaligned reference is undefined behavior (even if that reference is never dereferenced)
+
+error: aborting due to 4 previous errors
+

src/test/ui/unsafe/unsafe-unstable-const-fn.rs

@@ -0,0 +1,13 @@
+#![stable(feature = "foo", since = "1.33.0")]
+#![feature(staged_api)]
+#![feature(const_compare_raw_pointers)]
+#![feature(const_fn)]
+
+#[stable(feature = "foo", since = "1.33.0")]
+#[rustc_const_unstable(feature = "const_foo", issue = "none")]
+const fn unstable(a: *const i32, b: *const i32) -> bool {
+    a == b
+    //~^ pointer operation is unsafe
+}
+
+fn main() {}

src/test/ui/unsafe/unsafe-unstable-const-fn.stderr

@@ -0,0 +1,11 @@
+error[E0133]: pointer operation is unsafe and requires unsafe function or block
+  --> $DIR/unsafe-unstable-const-fn.rs:9:5
+   |
+LL |     a == b
+   |     ^^^^^^ pointer operation
+   |
+   = note: operations on pointers in constants
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0133`.

src/test/ui/unused-crate-deps/auxiliary/bar.rs

@@ -0,0 +1 @@
+pub const BAR: &str = "bar";

src/test/ui/unused-crate-deps/auxiliary/foo.rs

@@ -0,0 +1,5 @@
+// edition:2018
+// aux-crate:bar=bar.rs
+
+pub const FOO: &str = "foo";
+pub use bar::BAR;

src/test/ui/unused-crate-deps/libfib.rs

@@ -0,0 +1,21 @@
+// Test warnings for a library crate
+
+// check-pass
+// aux-crate:bar=bar.rs
+// compile-flags:--crate-type lib -Wunused-crate-dependencies
+
+pub fn fib(n: u32) -> Vec<u32> {
+//~^ WARNING external crate `bar` unused in
+let mut prev = 0;
+    let mut cur = 1;
+    let mut v = vec![];
+
+    for _ in 0..n {
+        v.push(prev);
+        let n = prev + cur;
+        prev = cur;
+        cur = n;
+    }
+
+    v
+}

src/test/ui/unused-crate-deps/libfib.stderr

@@ -0,0 +1,10 @@
+warning: external crate `bar` unused in `libfib`: remove the dependency or add `use bar as _;`
+  --> $DIR/libfib.rs:7:1
+   |
+LL | pub fn fib(n: u32) -> Vec<u32> {
+   | ^
+   |
+   = note: requested on the command line with `-W unused-crate-dependencies`
+
+warning: 1 warning emitted
+

src/test/ui/unused-crate-deps/suppress.rs

@@ -0,0 +1,11 @@
+// Suppress by using crate
+
+// edition:2018
+// check-pass
+// aux-crate:bar=bar.rs
+
+#![warn(unused_crate_dependencies)]
+
+use bar as _;
+
+fn main() {}

src/test/ui/unused-crate-deps/unused-aliases.rs

@@ -0,0 +1,13 @@
+// Warn about unused aliased for the crate
+
+// edition:2018
+// check-pass
+// aux-crate:bar=bar.rs
+// aux-crate:barbar=bar.rs
+
+#![warn(unused_crate_dependencies)]
+//~^ WARNING external crate `barbar` unused in
+
+use bar as _;
+
+fn main() {}

src/test/ui/unused-crate-deps/unused-aliases.stderr

@@ -0,0 +1,14 @@
+warning: external crate `barbar` unused in `unused_aliases`: remove the dependency or add `use barbar as _;`
+  --> $DIR/unused-aliases.rs:8:1
+   |
+LL | #![warn(unused_crate_dependencies)]
+   | ^
+   |
+note: the lint level is defined here
+  --> $DIR/unused-aliases.rs:8:9
+   |
+LL | #![warn(unused_crate_dependencies)]
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^
+
+warning: 1 warning emitted
+

src/test/ui/unused-crate-deps/use_extern_crate_2015.rs

@@ -0,0 +1,13 @@
+// Suppress by using crate
+
+// edition:2015
+// check-pass
+// aux-crate:bar=bar.rs
+
+#![warn(unused_crate_dependencies)]
+
+extern crate bar;
+
+fn main() {
+    println!("bar {}", bar::BAR);
+}

src/test/ui/unused-crate-deps/warn-attr.rs

@@ -0,0 +1,10 @@
+// Check for unused crate dep, no path
+
+// edition:2018
+// check-pass
+// aux-crate:bar=bar.rs
+
+#![warn(unused_crate_dependencies)]
+//~^ WARNING external crate `bar` unused in
+
+fn main() {}

src/test/ui/unused-crate-deps/warn-attr.stderr

@@ -0,0 +1,14 @@
+warning: external crate `bar` unused in `warn_attr`: remove the dependency or add `use bar as _;`
+  --> $DIR/warn-attr.rs:7:1
+   |
+LL | #![warn(unused_crate_dependencies)]
+   | ^
+   |
+note: the lint level is defined here
+  --> $DIR/warn-attr.rs:7:9
+   |
+LL | #![warn(unused_crate_dependencies)]
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^
+
+warning: 1 warning emitted
+

src/test/ui/unused-crate-deps/warn-cmdline-static.rs

@@ -0,0 +1,10 @@
+// Check for unused crate dep, no path
+
+// edition:2018
+// check-pass
+// compile-flags: -Wunused-crate-dependencies
+// aux-crate:bar=bar.rs
+// no-prefer-dynamic
+
+fn main() {}
+//~^ WARNING external crate `bar` unused in

src/test/ui/unused-crate-deps/warn-cmdline-static.stderr

@@ -0,0 +1,10 @@
+warning: external crate `bar` unused in `warn_cmdline_static`: remove the dependency or add `use bar as _;`
+  --> $DIR/warn-cmdline-static.rs:9:1
+   |
+LL | fn main() {}
+   | ^
+   |
+   = note: requested on the command line with `-W unused-crate-dependencies`
+
+warning: 1 warning emitted
+

src/test/ui/unused-crate-deps/warn-cmdline.rs

@@ -0,0 +1,9 @@
+// Check for unused crate dep, no path
+
+// edition:2018
+// check-pass
+// compile-flags: -Wunused-crate-dependencies
+// aux-crate:bar=bar.rs
+
+fn main() {}
+//~^ WARNING external crate `bar` unused in

src/test/ui/unused-crate-deps/warn-cmdline.stderr

@@ -0,0 +1,10 @@
+warning: external crate `bar` unused in `warn_cmdline`: remove the dependency or add `use bar as _;`
+  --> $DIR/warn-cmdline.rs:8:1
+   |
+LL | fn main() {}
+   | ^
+   |
+   = note: requested on the command line with `-W unused-crate-dependencies`
+
+warning: 1 warning emitted
+