Rollup of 11 pull requests

compiler/rustc_borrowck/src/region_infer/mod.rs

@@ -417,7 +417,7 @@ impl<'tcx> RegionInferenceContext<'tcx> {
     /// minimum values.
     ///
     /// For example:
-    /// ```
+    /// ```ignore (illustrative)
     /// fn foo<'a, 'b>( /* ... */ ) where 'a: 'b { /* ... */ }
     /// ```
     /// would initialize two variables like so:

compiler/rustc_hir/src/def.rs

@@ -360,7 +360,7 @@ impl DefKind {
 /// For example, everything prefixed with `/* Res */` in this example has
 /// an associated `Res`:
 ///
-/// ```
+/// ```ignore (illustrative)
 /// fn str_to_string(s: & /* Res */ str) -> /* Res */ String {
 ///     /* Res */ String::from(/* Res */ s)
 /// }
@@ -421,7 +421,7 @@ pub enum Res<Id = hir::HirId> {
     /// }
     ///
     /// impl Foo for Bar {
-    ///     fn foo() -> Box<Self> { // SelfTyAlias
+    ///     fn foo() -> Box<Self /* SelfTyAlias */> {
     ///         let _: Self;        // SelfTyAlias
     ///
     ///         todo!()

compiler/rustc_hir/src/hir.rs

@@ -3016,7 +3016,7 @@ impl fmt::Display for LoopIdError {
     }
 }
 
-#[derive(Copy, Clone, Debug, HashStable_Generic)]
+#[derive(Copy, Clone, Debug, PartialEq, HashStable_Generic)]
 pub struct Destination {
     /// This is `Some(_)` iff there is an explicit user-specified 'label
     pub label: Option<Label>,

compiler/rustc_hir_analysis/src/check/compare_impl_item.rs

@@ -425,7 +425,7 @@ impl<'tcx> TypeFolder<TyCtxt<'tcx>> for RemapLateParam<'tcx> {
 ///
 /// trait Foo {
 ///     fn bar() -> impl Deref<Target = impl Sized>;
-///              // ^- RPITIT #1        ^- RPITIT #2
+///     //          ^- RPITIT #1        ^- RPITIT #2
 /// }
 ///
 /// impl Foo for () {

compiler/rustc_hir_typeck/src/loops.rs

@@ -2,7 +2,6 @@ use std::collections::BTreeMap;
 use std::fmt;
 
 use Context::*;
-use rustc_ast::Label;
 use rustc_hir as hir;
 use rustc_hir::attrs::AttributeKind;
 use rustc_hir::def::DefKind;
@@ -42,8 +41,8 @@ enum Context {
     ConstBlock,
     /// E.g. `#[loop_match] loop { state = 'label: { /* ... */ } }`.
     LoopMatch {
-        /// The label of the labeled block (not of the loop itself).
-        labeled_block: Label,
+        /// The destination pointing to the labeled block (not to the loop itself).
+        labeled_block: Destination,
     },
 }
 
@@ -186,18 +185,18 @@ impl<'hir> Visitor<'hir> for CheckLoopVisitor<'hir> {
             {
                 self.with_context(UnlabeledBlock(b.span.shrink_to_lo()), |v| v.visit_block(b));
             }
-            hir::ExprKind::Break(break_label, ref opt_expr) => {
+            hir::ExprKind::Break(break_destination, ref opt_expr) => {
                 if let Some(e) = opt_expr {
                     self.visit_expr(e);
                 }
 
-                if self.require_label_in_labeled_block(e.span, &break_label, "break") {
+                if self.require_label_in_labeled_block(e.span, &break_destination, "break") {
                     // If we emitted an error about an unlabeled break in a labeled
                     // block, we don't need any further checking for this break any more
                     return;
                 }
 
-                let loop_id = match break_label.target_id {
+                let loop_id = match break_destination.target_id {
                     Ok(loop_id) => Some(loop_id),
                     Err(hir::LoopIdError::OutsideLoopScope) => None,
                     Err(hir::LoopIdError::UnlabeledCfInWhileCondition) => {
@@ -212,18 +211,25 @@ impl<'hir> Visitor<'hir> for CheckLoopVisitor<'hir> {
 
                 // A `#[const_continue]` must break to a block in a `#[loop_match]`.
                 if find_attr!(self.tcx.hir_attrs(e.hir_id), AttributeKind::ConstContinue(_)) {
-                    if let Some(break_label) = break_label.label {
-                        let is_target_label = |cx: &Context| match cx {
-                            Context::LoopMatch { labeled_block } => {
-                                break_label.ident.name == labeled_block.ident.name
-                            }
-                            _ => false,
-                        };
+                    let Some(label) = break_destination.label else {
+                        let span = e.span;
+                        self.tcx.dcx().emit_fatal(ConstContinueBadLabel { span });
+                    };
 
-                        if !self.cx_stack.iter().rev().any(is_target_label) {
-                            let span = break_label.ident.span;
-                            self.tcx.dcx().emit_fatal(ConstContinueBadLabel { span });
+                    let is_target_label = |cx: &Context| match cx {
+                        Context::LoopMatch { labeled_block } => {
+                            // NOTE: with macro expansion, the label's span might be different here
+                            // even though it does still refer to the same HIR node. A block
+                            // can't have two labels, so the hir_id is a unique identifier.
+                            assert!(labeled_block.target_id.is_ok()); // see `is_loop_match`.
+                            break_destination.target_id == labeled_block.target_id
                         }
+                        _ => false,
+                    };
+
+                    if !self.cx_stack.iter().rev().any(is_target_label) {
+                        let span = label.ident.span;
+                        self.tcx.dcx().emit_fatal(ConstContinueBadLabel { span });
                     }
                 }
 
@@ -249,7 +255,7 @@ impl<'hir> Visitor<'hir> for CheckLoopVisitor<'hir> {
                         Some(kind) => {
                             let suggestion = format!(
                                 "break{}",
-                                break_label
+                                break_destination
                                     .label
                                     .map_or_else(String::new, |l| format!(" {}", l.ident))
                             );
@@ -259,7 +265,7 @@ impl<'hir> Visitor<'hir> for CheckLoopVisitor<'hir> {
                                 kind: kind.name(),
                                 suggestion,
                                 loop_label,
-                                break_label: break_label.label,
+                                break_label: break_destination.label,
                                 break_expr_kind: &break_expr.kind,
                                 break_expr_span: break_expr.span,
                             });
@@ -268,7 +274,7 @@ impl<'hir> Visitor<'hir> for CheckLoopVisitor<'hir> {
                 }
 
                 let sp_lo = e.span.with_lo(e.span.lo() + BytePos("break".len() as u32));
-                let label_sp = match break_label.label {
+                let label_sp = match break_destination.label {
                     Some(label) => sp_lo.with_hi(label.ident.span.hi()),
                     None => sp_lo.shrink_to_lo(),
                 };
@@ -416,7 +422,7 @@ impl<'hir> CheckLoopVisitor<'hir> {
         &self,
         e: &'hir hir::Expr<'hir>,
         body: &'hir hir::Block<'hir>,
-    ) -> Option<Label> {
+    ) -> Option<Destination> {
         if !find_attr!(self.tcx.hir_attrs(e.hir_id), AttributeKind::LoopMatch(_)) {
             return None;
         }
@@ -438,8 +444,8 @@ impl<'hir> CheckLoopVisitor<'hir> {
 
         let hir::ExprKind::Assign(_, rhs_expr, _) = loop_body_expr.kind else { return None };
 
-        let hir::ExprKind::Block(_, label) = rhs_expr.kind else { return None };
+        let hir::ExprKind::Block(block, label) = rhs_expr.kind else { return None };
 
-        label
+        Some(Destination { label, target_id: Ok(block.hir_id) })
     }
 }

compiler/rustc_hir_typeck/src/upvar.rs

@@ -2391,13 +2391,11 @@ fn migration_suggestion_for_2229(
 /// let mut p = Point { x: 10, y: 10 };
 ///
 /// let c = || {
-///     p.x     += 10;
-/// // ^ E1 ^
+///     p.x += 10; // E1
 ///     // ...
 ///     // More code
 ///     // ...
 ///     p.x += 10; // E2
-/// // ^ E2 ^
 /// };
 /// ```
 /// `CaptureKind` associated with both `E1` and `E2` will be ByRef(MutBorrow),

compiler/rustc_infer/src/infer/outlives/obligations.rs

@@ -36,7 +36,7 @@
 //! fn bar<T>(a: T, b: impl for<'a> Fn(&'a T)) {}
 //! fn foo<T>(x: T) {
 //!     bar(x, |y| { /* ... */})
-//!          // ^ closure arg
+//!     //      ^ closure arg
 //! }
 //! ```
 //!

compiler/rustc_middle/src/hir/map.rs

@@ -533,8 +533,10 @@ impl<'tcx> TyCtxt<'tcx> {
     /// ```
     /// fn foo(x: usize) -> bool {
     ///     if x == 1 {
-    ///         true  // If `get_fn_id_for_return_block` gets passed the `id` corresponding
-    ///     } else {  // to this, it will return `foo`'s `HirId`.
+    ///         // If `get_fn_id_for_return_block` gets passed the `id` corresponding to this, it
+    ///         // will return `foo`'s `HirId`.
+    ///         true
+    ///     } else {
     ///         false
     ///     }
     /// }
@@ -543,8 +545,10 @@ impl<'tcx> TyCtxt<'tcx> {
     /// ```compile_fail,E0308
     /// fn foo(x: usize) -> bool {
     ///     loop {
-    ///         true  // If `get_fn_id_for_return_block` gets passed the `id` corresponding
-    ///     }         // to this, it will return `None`.
+    ///         // If `get_fn_id_for_return_block` gets passed the `id` corresponding to this, it
+    ///         // will return `None`.
+    ///         true
+    ///     }
     ///     false
     /// }
     /// ```

compiler/rustc_middle/src/mir/mod.rs

@@ -1017,7 +1017,8 @@ pub struct LocalDecl<'tcx> {
     /// ```
     /// fn foo(x: &str) {
     ///     #[allow(unused_mut)]
-    ///     let mut x: u32 = { // <- one unused mut
+    ///     let mut x: u32 = {
+    ///         //^ one unused mut
     ///         let mut y: u32 = x.parse().unwrap();
     ///         y + 2
     ///     };

compiler/rustc_mir_build/messages.ftl

@@ -87,7 +87,7 @@ mir_build_confused = missing patterns are not covered because `{$variable}` is i
 mir_build_const_continue_bad_const = could not determine the target branch for this `#[const_continue]`
     .label = this value is too generic
 
-mir_build_const_continue_missing_value = a `#[const_continue]` must break to a label with a value
+mir_build_const_continue_missing_label_or_value = a `#[const_continue]` must break to a label with a value
 
 mir_build_const_continue_not_const = could not determine the target branch for this `#[const_continue]`
     .help = try extracting the expression into a `const` item

compiler/rustc_mir_build/src/builder/expr/as_operand.rs

@@ -57,7 +57,9 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
     /// ```
     /// #![feature(unsized_fn_params)]
     /// # use core::fmt::Debug;
-    /// fn foo(_p: dyn Debug) { /* ... */ }
+    /// fn foo(_p: dyn Debug) {
+    ///     /* ... */
+    /// }
     ///
     /// fn bar(box_p: Box<dyn Debug>) { foo(*box_p); }
     /// ```

compiler/rustc_mir_build/src/errors.rs

@@ -1254,8 +1254,8 @@ pub(crate) struct ConstContinueBadConst {
 }
 
 #[derive(Diagnostic)]
-#[diag(mir_build_const_continue_missing_value)]
-pub(crate) struct ConstContinueMissingValue {
+#[diag(mir_build_const_continue_missing_label_or_value)]
+pub(crate) struct ConstContinueMissingLabelOrValue {
     #[primary_span]
     pub span: Span,
 }

compiler/rustc_mir_build/src/thir/cx/expr.rs

@@ -852,9 +852,9 @@ impl<'tcx> ThirBuildCx<'tcx> {
                 if find_attr!(self.tcx.hir_attrs(expr.hir_id), AttributeKind::ConstContinue(_)) {
                     match dest.target_id {
                         Ok(target_id) => {
-                            let Some(value) = value else {
+                            let (Some(value), Some(_)) = (value, dest.label) else {
                                 let span = expr.span;
-                                self.tcx.dcx().emit_fatal(ConstContinueMissingValue { span })
+                                self.tcx.dcx().emit_fatal(ConstContinueMissingLabelOrValue { span })
                             };
 
                             ExprKind::ConstContinue {

compiler/rustc_mir_dataflow/src/impls/initialized.rs

@@ -108,6 +108,7 @@ impl<'tcx> MaybePlacesSwitchIntData<'tcx> {
 ///
 /// ```rust
 /// struct S;
+/// #[rustfmt::skip]
 /// fn foo(pred: bool) {                        // maybe-init:
 ///                                             // {}
 ///     let a = S; let mut b = S; let c; let d; // {a, b}
@@ -197,6 +198,7 @@ impl<'a, 'tcx> HasMoveData<'tcx> for MaybeInitializedPlaces<'a, 'tcx> {
 ///
 /// ```rust
 /// struct S;
+/// #[rustfmt::skip]
 /// fn foo(pred: bool) {                        // maybe-uninit:
 ///                                             // {a, b, c, d}
 ///     let a = S; let mut b = S; let c; let d; // {      c, d}
@@ -289,6 +291,7 @@ impl<'tcx> HasMoveData<'tcx> for MaybeUninitializedPlaces<'_, 'tcx> {
 ///
 /// ```rust
 /// struct S;
+/// #[rustfmt::skip]
 /// fn foo(pred: bool) {                        // ever-init:
 ///                                             // {          }
 ///     let a = S; let mut b = S; let c; let d; // {a, b      }

compiler/rustc_mir_transform/src/ctfe_limit.rs

@@ -18,7 +18,7 @@ impl<'tcx> crate::MirPass<'tcx> for CtfeLimit {
             .basic_blocks
             .iter_enumerated()
             .filter_map(|(node, node_data)| {
-                if matches!(node_data.terminator().kind, TerminatorKind::Call { .. })
+                if matches!(node_data.terminator().kind, TerminatorKind::Call { .. } | TerminatorKind::TailCall { .. })
                     // Back edges in a CFG indicate loops
                     || has_back_edge(doms, node, node_data)
                 {

compiler/rustc_mir_transform/src/elaborate_drop.rs

@@ -611,6 +611,7 @@ where
     ///
     /// For example, with 3 fields, the drop ladder is
     ///
+    /// ```text
     /// .d0:
     ///     ELAB(drop location.0 [target=.d1, unwind=.c1])
     /// .d1:
@@ -621,8 +622,10 @@ where
     ///     ELAB(drop location.1 [target=.c2])
     /// .c2:
     ///     ELAB(drop location.2 [target=`self.unwind`])
+    /// ```
     ///
     /// For possible-async drops in coroutines we also need dropline ladder
+    /// ```text
     /// .d0 (mainline):
     ///     ELAB(drop location.0 [target=.d1, unwind=.c1, drop=.e1])
     /// .d1 (mainline):
@@ -637,6 +640,7 @@ where
     ///     ELAB(drop location.1 [target=.e2, unwind=.c2])
     /// .e2 (dropline):
     ///     ELAB(drop location.2 [target=`self.drop`, unwind=`self.unwind`])
+    /// ```
     ///
     /// NOTE: this does not clear the master drop flag, so you need
     /// to point succ/unwind on a `drop_ladder_bottom`.

compiler/rustc_span/src/hygiene.rs

@@ -768,7 +768,9 @@ impl SyntaxContext {
     ///
     /// ```rust
     /// #![feature(decl_macro)]
-    /// mod foo { pub fn f() {} } // `f`'s `SyntaxContext` is empty.
+    /// mod foo {
+    ///     pub fn f() {} // `f`'s `SyntaxContext` is empty.
+    /// }
     /// m!(f);
     /// macro m($f:ident) {
     ///     mod bar {

compiler/rustc_thread_pool/src/scope/mod.rs

@@ -501,9 +501,9 @@ impl<'scope> Scope<'scope> {
     /// let mut value_c = None;
     /// rayon::scope(|s| {
     ///     s.spawn(|s1| {
-    ///           // ^ this is the same scope as `s`; this handle `s1`
-    ///           //   is intended for use by the spawned task,
-    ///           //   since scope handles cannot cross thread boundaries.
+    ///         //   ^ this is the same scope as `s`; this handle `s1`
+    ///         //     is intended for use by the spawned task,
+    ///         //     since scope handles cannot cross thread boundaries.
     ///
     ///         value_a = Some(22);
     ///

compiler/rustc_thread_pool/src/sleep/mod.rs

@@ -44,7 +44,7 @@ impl SleepData {
 /// jobs are published, and it either blocks threads or wakes them in response to these
 /// events. See the [`README.md`] in this module for more details.
 ///
-/// [`README.md`] README.md
+/// [`README.md`]: README.md
 pub(super) struct Sleep {
     /// One "sleep state" per worker. Used to track if a worker is sleeping and to have
     /// them block.

library/alloc/src/string.rs

@@ -265,12 +265,12 @@ use crate::vec::{self, Vec};
 /// You can look at these with the [`as_ptr`], [`len`], and [`capacity`]
 /// methods:
 ///
+// FIXME Update this when vec_into_raw_parts is stabilized
 /// ```
 /// use std::mem;
 ///
 /// let story = String::from("Once upon a time...");
 ///
-// FIXME Update this when vec_into_raw_parts is stabilized
 /// // Prevent automatically dropping the String's data
 /// let mut story = mem::ManuallyDrop::new(story);
 ///
@@ -970,13 +970,13 @@ impl String {
     ///
     /// # Examples
     ///
+    // FIXME Update this when vec_into_raw_parts is stabilized
     /// ```
     /// use std::mem;
     ///
     /// unsafe {
     ///     let s = String::from("hello");
     ///
-    // FIXME Update this when vec_into_raw_parts is stabilized
     ///     // Prevent automatically dropping the String's data
     ///     let mut s = mem::ManuallyDrop::new(s);
     ///