Rollup of 6 pull requests

Cargo.lock

@@ -2,23 +2,14 @@
 # It is not intended for manual editing.
 version = 3
 
-[[package]]
-name = "addr2line"
-version = "0.20.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f4fa78e18c64fce05e902adecd7a5eed15a5e0a3439f7b0e169f0252214865e3"
-dependencies = [
- "gimli 0.27.3",
-]
-
 [[package]]
 name = "addr2line"
 version = "0.21.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "8a30b2e23b9e17a9f90641c7ab1549cd9b44f296d3ccbf309d2863cfe398a0cb"
 dependencies = [
  "compiler_builtins",
- "gimli 0.28.0",
+ "gimli",
  "rustc-std-workspace-alloc",
  "rustc-std-workspace-core",
 ]
@@ -180,7 +171,7 @@ version = "0.1.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "9792d37ca5173d7e7f4fe453739a0671d0557915a030a383d6b866476bbc3e71"
 dependencies = [
- "object 0.32.0",
+ "object",
 ]
 
 [[package]]
@@ -246,16 +237,16 @@ checksum = "d468802bab17cbc0cc575e9b053f41e72aa36bfa6b7f55e3529ffa43161b97fa"
 
 [[package]]
 name = "backtrace"
-version = "0.3.68"
+version = "0.3.69"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "4319208da049c43661739c5fade2ba182f09d1dc2299b32298d3a31692b17e12"
+checksum = "2089b7e3f35b9dd2d0ed921ead4f6d318c27680d4a5bd167b3ee120edb105837"
 dependencies = [
- "addr2line 0.20.0",
+ "addr2line",
  "cc",
  "cfg-if",
  "libc",
  "miniz_oxide",
- "object 0.31.1",
+ "object",
  "rustc-demangle",
 ]
 
@@ -1435,12 +1426,6 @@ dependencies = [
  "wasi",
 ]
 
-[[package]]
-name = "gimli"
-version = "0.27.3"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b6c80984affa11d98d1b88b66ac8853f143217b399d3c74116778ff8fdb4ed2e"
-
 [[package]]
 name = "gimli"
 version = "0.28.0"
@@ -2430,15 +2415,6 @@ dependencies = [
  "libc",
 ]
 
-[[package]]
-name = "object"
-version = "0.31.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "8bda667d9f2b5051b8833f59f3bf748b28ef54f850f4fcb389a252aa383866d1"
-dependencies = [
- "memchr",
-]
-
 [[package]]
 name = "object"
 version = "0.32.0"
@@ -3357,7 +3333,7 @@ dependencies = [
  "cstr",
  "libc",
  "measureme",
- "object 0.32.0",
+ "object",
  "rustc-demangle",
  "rustc_ast",
  "rustc_attr",
@@ -3393,7 +3369,7 @@ dependencies = [
  "itertools",
  "jobserver",
  "libc",
- "object 0.32.0",
+ "object",
  "pathdiff",
  "regex",
  "rustc_arena",
@@ -4327,7 +4303,7 @@ name = "rustc_target"
 version = "0.0.0"
 dependencies = [
  "bitflags 1.3.2",
- "object 0.32.0",
+ "object",
  "rustc_abi",
  "rustc_data_structures",
  "rustc_feature",
@@ -4856,7 +4832,7 @@ checksum = "a2eb9349b6444b326872e140eb1cf5e7c522154d69e7a0ffb0fb81c06b37543f"
 name = "std"
 version = "0.0.0"
 dependencies = [
- "addr2line 0.21.0",
+ "addr2line",
  "alloc",
  "cfg-if",
  "compiler_builtins",
@@ -4867,7 +4843,7 @@ dependencies = [
  "hermit-abi 0.3.2",
  "libc",
  "miniz_oxide",
- "object 0.32.0",
+ "object",
  "panic_abort",
  "panic_unwind",
  "profiler_builtins",
@@ -5171,9 +5147,9 @@ version = "0.7.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "4db52ee8fec06e119b692ef3dd2c4cf621a99204c1b8c47407870ed050305b9b"
 dependencies = [
- "gimli 0.28.0",
+ "gimli",
  "hashbrown 0.14.0",
- "object 0.32.0",
+ "object",
  "tracing",
 ]
 

compiler/rustc_lint/messages.ftl

@@ -323,6 +323,8 @@ lint_invalid_reference_casting_assign_to_ref = assigning to `&T` is undefined be
 lint_invalid_reference_casting_borrow_as_mut = casting `&T` to `&mut T` is undefined behavior, even if the reference is unused, consider instead using an `UnsafeCell`
     .label = casting happend here
 
+lint_invalid_reference_casting_note_book = for more information, visit <https://doc.rust-lang.org/book/ch15-05-interior-mutability.html>
+
 lint_lintpass_by_hand = implementing `LintPass` by hand
     .help = try using `declare_lint_pass!` or `impl_lint_pass!` instead
 

compiler/rustc_lint/src/lints.rs

@@ -764,11 +764,13 @@ pub enum InvalidFromUtf8Diag {
 #[derive(LintDiagnostic)]
 pub enum InvalidReferenceCastingDiag {
     #[diag(lint_invalid_reference_casting_borrow_as_mut)]
+    #[note(lint_invalid_reference_casting_note_book)]
     BorrowAsMut {
         #[label]
         orig_cast: Option<Span>,
     },
     #[diag(lint_invalid_reference_casting_assign_to_ref)]
+    #[note(lint_invalid_reference_casting_note_book)]
     AssignToRef {
         #[label]
         orig_cast: Option<Span>,

compiler/rustc_lint/src/reference_casting.rs

@@ -56,20 +56,7 @@ impl<'tcx> LateLintPass<'tcx> for InvalidReferenceCasting {
     }
 
     fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx Expr<'tcx>) {
-        // &mut <expr>
-        let inner = if let ExprKind::AddrOf(_, Mutability::Mut, expr) = expr.kind {
-            expr
-        // <expr> = ...
-        } else if let ExprKind::Assign(expr, _, _) = expr.kind {
-            expr
-        // <expr> += ...
-        } else if let ExprKind::AssignOp(_, expr, _) = expr.kind {
-            expr
-        } else {
-            return;
-        };
-
-        let ExprKind::Unary(UnOp::Deref, e) = &inner.kind else {
+        let Some((is_assignment, e)) = is_operation_we_care_about(cx, expr) else {
             return;
         };
 
@@ -86,15 +73,58 @@ impl<'tcx> LateLintPass<'tcx> for InvalidReferenceCasting {
         cx.emit_spanned_lint(
             INVALID_REFERENCE_CASTING,
             expr.span,
-            if matches!(expr.kind, ExprKind::AddrOf(..)) {
-                InvalidReferenceCastingDiag::BorrowAsMut { orig_cast }
-            } else {
+            if is_assignment {
                 InvalidReferenceCastingDiag::AssignToRef { orig_cast }
+            } else {
+                InvalidReferenceCastingDiag::BorrowAsMut { orig_cast }
             },
         );
     }
 }
 
+fn is_operation_we_care_about<'tcx>(
+    cx: &LateContext<'tcx>,
+    e: &'tcx Expr<'tcx>,
+) -> Option<(bool, &'tcx Expr<'tcx>)> {
+    fn deref_assign_or_addr_of<'tcx>(expr: &'tcx Expr<'tcx>) -> Option<(bool, &'tcx Expr<'tcx>)> {
+        // &mut <expr>
+        let inner = if let ExprKind::AddrOf(_, Mutability::Mut, expr) = expr.kind {
+            expr
+        // <expr> = ...
+        } else if let ExprKind::Assign(expr, _, _) = expr.kind {
+            expr
+        // <expr> += ...
+        } else if let ExprKind::AssignOp(_, expr, _) = expr.kind {
+            expr
+        } else {
+            return None;
+        };
+
+        if let ExprKind::Unary(UnOp::Deref, e) = &inner.kind {
+            Some((!matches!(expr.kind, ExprKind::AddrOf(..)), e))
+        } else {
+            None
+        }
+    }
+
+    fn ptr_write<'tcx>(
+        cx: &LateContext<'tcx>,
+        e: &'tcx Expr<'tcx>,
+    ) -> Option<(bool, &'tcx Expr<'tcx>)> {
+        if let ExprKind::Call(path, [arg_ptr, _arg_val]) = e.kind
+            && let ExprKind::Path(ref qpath) = path.kind
+            && let Some(def_id) = cx.qpath_res(qpath, path.hir_id).opt_def_id()
+            && matches!(cx.tcx.get_diagnostic_name(def_id), Some(sym::ptr_write | sym::ptr_write_volatile | sym::ptr_write_unaligned))
+        {
+            Some((true, arg_ptr))
+        } else {
+            None
+        }
+    }
+
+    deref_assign_or_addr_of(e).or_else(|| ptr_write(cx, e))
+}
+
 fn is_cast_from_const_to_mut<'tcx>(cx: &LateContext<'tcx>, e: &'tcx Expr<'tcx>) -> bool {
     let e = e.peel_blocks();
 

compiler/rustc_span/src/symbol.rs

@@ -1179,6 +1179,9 @@ symbols! {
         ptr_offset_from,
         ptr_offset_from_unsigned,
         ptr_unique,
+        ptr_write,
+        ptr_write_unaligned,
+        ptr_write_volatile,
         pub_macro_rules,
         pub_restricted,
         public,

library/core/src/ptr/mod.rs

@@ -1357,6 +1357,7 @@ pub const unsafe fn read_unaligned<T>(src: *const T) -> T {
 #[inline]
 #[stable(feature = "rust1", since = "1.0.0")]
 #[rustc_const_unstable(feature = "const_ptr_write", issue = "86302")]
+#[rustc_diagnostic_item = "ptr_write"]
 #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces
 pub const unsafe fn write<T>(dst: *mut T, src: T) {
     // Semantically, it would be fine for this to be implemented as a
@@ -1459,6 +1460,7 @@ pub const unsafe fn write<T>(dst: *mut T, src: T) {
 #[inline]
 #[stable(feature = "ptr_unaligned", since = "1.17.0")]
 #[rustc_const_unstable(feature = "const_ptr_write", issue = "86302")]
+#[rustc_diagnostic_item = "ptr_write_unaligned"]
 #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces
 pub const unsafe fn write_unaligned<T>(dst: *mut T, src: T) {
     // SAFETY: the caller must guarantee that `dst` is valid for writes.
@@ -1607,6 +1609,7 @@ pub unsafe fn read_volatile<T>(src: *const T) -> T {
 /// ```
 #[inline]
 #[stable(feature = "volatile", since = "1.9.0")]
+#[rustc_diagnostic_item = "ptr_write_volatile"]
 #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces
 pub unsafe fn write_volatile<T>(dst: *mut T, src: T) {
     // SAFETY: the caller must uphold the safety contract for `volatile_store`.

library/std/src/keyword_docs.rs

@@ -1820,7 +1820,7 @@ mod true_keyword {}
 
 #[doc(keyword = "type")]
 //
-/// Define an alias for an existing type.
+/// Define an [alias] for an existing type.
 ///
 /// The syntax is `type Name = ExistingType;`.
 ///
@@ -1838,6 +1838,13 @@ mod true_keyword {}
 /// assert_eq!(m, k);
 /// ```
 ///
+/// A type can be generic:
+///
+/// ```rust
+/// # use std::sync::{Arc, Mutex};
+/// type ArcMutex<T> = Arc<Mutex<T>>;
+/// ```
+///
 /// In traits, `type` is used to declare an [associated type]:
 ///
 /// ```rust
@@ -1860,6 +1867,7 @@ mod true_keyword {}
 ///
 /// [`trait`]: keyword.trait.html
 /// [associated type]: ../reference/items/associated-items.html#associated-types
+/// [alias]: ../reference/items/type-aliases.html
 mod type_keyword {}
 
 #[doc(keyword = "unsafe")]

src/tools/clippy/clippy_utils/src/hir_utils.rs

@@ -10,6 +10,7 @@ use rustc_hir::{
     GenericArgs, Guard, HirId, HirIdMap, InlineAsmOperand, Let, Lifetime, LifetimeName, Pat, PatField, PatKind, Path,
     PathSegment, PrimTy, QPath, Stmt, StmtKind, Ty, TyKind, TypeBinding,
 };
+use rustc_hir::MatchSource::TryDesugar;
 use rustc_lexer::{tokenize, TokenKind};
 use rustc_lint::LateContext;
 use rustc_middle::ty::TypeckResults;
@@ -311,7 +312,7 @@ impl HirEqInterExpr<'_, '_, '_> {
                 lls == rls && self.eq_block(lb, rb) && both(ll, rl, |l, r| l.ident.name == r.ident.name)
             },
             (&ExprKind::Match(le, la, ref ls), &ExprKind::Match(re, ra, ref rs)) => {
-                ls == rs
+                (ls == rs || (matches!((ls, rs), (TryDesugar(_), TryDesugar(_)))))
                     && self.eq_expr(le, re)
                     && over(la, ra, |l, r| {
                         self.eq_pat(l.pat, r.pat)

src/tools/clippy/tests/ui/if_same_then_else2.rs

@@ -98,7 +98,7 @@ fn if_same_then_else2() -> Result<&'static str, ()> {
     };
 
     if true {
-        // FIXME: should emit "this `if` has identical blocks"
+        //~^ ERROR: this `if` has identical blocks
         Ok("foo")?;
     } else {
         Ok("foo")?;

src/tools/clippy/tests/ui/if_same_then_else2.stderr

@@ -82,6 +82,25 @@ LL | |         f32::NAN
 LL | |     };
    | |_____^
 
+error: this `if` has identical blocks
+  --> $DIR/if_same_then_else2.rs:100:13
+   |
+LL |       if true {
+   |  _____________^
+LL | |
+LL | |         Ok("foo")?;
+LL | |     } else {
+   | |_____^
+   |
+note: same as this
+  --> $DIR/if_same_then_else2.rs:103:12
+   |
+LL |       } else {
+   |  ____________^
+LL | |         Ok("foo")?;
+LL | |     }
+   | |_____^
+
 error: this `if` has identical blocks
   --> $DIR/if_same_then_else2.rs:124:20
    |
@@ -103,5 +122,5 @@ LL | |         return Ok(&foo[0..]);
 LL | |     }
    | |_____^
 
-error: aborting due to 5 previous errors
+error: aborting due to 6 previous errors
 

tests/ui/const-generics/issues/issue-100313.stderr

@@ -4,6 +4,7 @@ error: assigning to `&T` is undefined behavior, consider using an `UnsafeCell`
 LL |             *(B as *const bool as *mut bool) = false;
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
+   = note: for more information, visit <https://doc.rust-lang.org/book/ch15-05-interior-mutability.html>
    = note: `#[deny(invalid_reference_casting)]` on by default
 
 error[E0080]: evaluation of constant value failed