Rollup of 7 pull requests

compiler/rustc_arena/src/lib.rs

@@ -19,6 +19,7 @@
 #![feature(rustc_attrs)]
 #![cfg_attr(test, feature(test))]
 #![feature(strict_provenance)]
+#![feature(ptr_const_cast)]
 
 use smallvec::SmallVec;
 
@@ -27,7 +28,7 @@ use std::cell::{Cell, RefCell};
 use std::cmp;
 use std::marker::{PhantomData, Send};
 use std::mem::{self, MaybeUninit};
-use std::ptr;
+use std::ptr::{self, NonNull};
 use std::slice;
 
 #[inline(never)]
@@ -55,15 +56,24 @@ pub struct TypedArena<T> {
 
 struct ArenaChunk<T = u8> {
     /// The raw storage for the arena chunk.
-    storage: Box<[MaybeUninit<T>]>,
+    storage: NonNull<[MaybeUninit<T>]>,
     /// The number of valid entries in the chunk.
     entries: usize,
 }
 
+unsafe impl<#[may_dangle] T> Drop for ArenaChunk<T> {
+    fn drop(&mut self) {
+        unsafe { Box::from_raw(self.storage.as_mut()) };
+    }
+}
+
 impl<T> ArenaChunk<T> {
     #[inline]
     unsafe fn new(capacity: usize) -> ArenaChunk<T> {
-        ArenaChunk { storage: Box::new_uninit_slice(capacity), entries: 0 }
+        ArenaChunk {
+            storage: NonNull::new(Box::into_raw(Box::new_uninit_slice(capacity))).unwrap(),
+            entries: 0,
+        }
     }
 
     /// Destroys this arena chunk.
@@ -72,14 +82,15 @@ impl<T> ArenaChunk<T> {
         // The branch on needs_drop() is an -O1 performance optimization.
         // Without the branch, dropping TypedArena<u8> takes linear time.
         if mem::needs_drop::<T>() {
-            ptr::drop_in_place(MaybeUninit::slice_assume_init_mut(&mut self.storage[..len]));
+            let slice = &mut *(self.storage.as_mut());
+            ptr::drop_in_place(MaybeUninit::slice_assume_init_mut(&mut slice[..len]));
         }
     }
 
     // Returns a pointer to the first allocated object.
     #[inline]
     fn start(&mut self) -> *mut T {
-        MaybeUninit::slice_as_mut_ptr(&mut self.storage)
+        self.storage.as_ptr() as *mut T
     }
 
     // Returns a pointer to the end of the allocated space.
@@ -90,7 +101,7 @@ impl<T> ArenaChunk<T> {
                 // A pointer as large as possible for zero-sized elements.
                 ptr::invalid_mut(!0)
             } else {
-                self.start().add(self.storage.len())
+                self.start().add((*self.storage.as_ptr()).len())
             }
         }
     }
@@ -274,7 +285,7 @@ impl<T> TypedArena<T> {
                 // If the previous chunk's len is less than HUGE_PAGE
                 // bytes, then this chunk will be least double the previous
                 // chunk's size.
-                new_cap = last_chunk.storage.len().min(HUGE_PAGE / elem_size / 2);
+                new_cap = (*last_chunk.storage.as_ptr()).len().min(HUGE_PAGE / elem_size / 2);
                 new_cap *= 2;
             } else {
                 new_cap = PAGE / elem_size;
@@ -382,7 +393,7 @@ impl DroplessArena {
                 // If the previous chunk's len is less than HUGE_PAGE
                 // bytes, then this chunk will be least double the previous
                 // chunk's size.
-                new_cap = last_chunk.storage.len().min(HUGE_PAGE / 2);
+                new_cap = (*last_chunk.storage.as_ptr()).len().min(HUGE_PAGE / 2);
                 new_cap *= 2;
             } else {
                 new_cap = PAGE;

compiler/rustc_arena/src/tests.rs

@@ -79,7 +79,11 @@ fn test_arena_alloc_nested() {
 #[test]
 pub fn test_copy() {
     let arena = TypedArena::default();
-    for _ in 0..100000 {
+    #[cfg(not(miri))]
+    const N: usize = 100000;
+    #[cfg(miri)]
+    const N: usize = 1000;
+    for _ in 0..N {
         arena.alloc(Point { x: 1, y: 2, z: 3 });
     }
 }
@@ -106,15 +110,23 @@ struct Noncopy {
 #[test]
 pub fn test_noncopy() {
     let arena = TypedArena::default();
-    for _ in 0..100000 {
+    #[cfg(not(miri))]
+    const N: usize = 100000;
+    #[cfg(miri)]
+    const N: usize = 1000;
+    for _ in 0..N {
         arena.alloc(Noncopy { string: "hello world".to_string(), array: vec![1, 2, 3, 4, 5] });
     }
 }
 
 #[test]
 pub fn test_typed_arena_zero_sized() {
     let arena = TypedArena::default();
-    for _ in 0..100000 {
+    #[cfg(not(miri))]
+    const N: usize = 100000;
+    #[cfg(miri)]
+    const N: usize = 1000;
+    for _ in 0..N {
         arena.alloc(());
     }
 }
@@ -124,7 +136,11 @@ pub fn test_typed_arena_clear() {
     let mut arena = TypedArena::default();
     for _ in 0..10 {
         arena.clear();
-        for _ in 0..10000 {
+        #[cfg(not(miri))]
+        const N: usize = 10000;
+        #[cfg(miri)]
+        const N: usize = 100;
+        for _ in 0..N {
             arena.alloc(Point { x: 1, y: 2, z: 3 });
         }
     }

compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs

@@ -1628,7 +1628,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
             location: Location,
         ) -> impl Iterator<Item = Location> + Captures<'tcx> + 'a {
             if location.statement_index == 0 {
-                let predecessors = body.predecessors()[location.block].to_vec();
+                let predecessors = body.basic_blocks.predecessors()[location.block].to_vec();
                 Either::Left(predecessors.into_iter().map(move |bb| body.terminator_loc(bb)))
             } else {
                 Either::Right(std::iter::once(Location {

compiler/rustc_borrowck/src/invalidation.rs

@@ -26,7 +26,7 @@ pub(super) fn generate_invalidates<'tcx>(
 
     if let Some(all_facts) = all_facts {
         let _prof_timer = tcx.prof.generic_activity("polonius_fact_generation");
-        let dominators = body.dominators();
+        let dominators = body.basic_blocks.dominators();
         let mut ig = InvalidationGenerator {
             all_facts,
             borrow_set,

compiler/rustc_borrowck/src/lib.rs

@@ -334,7 +334,7 @@ fn do_mir_borrowck<'a, 'tcx>(
         };
     }
 
-    let dominators = body.dominators();
+    let dominators = body.basic_blocks.dominators();
 
     let mut mbcx = MirBorrowckCtxt {
         infcx,

compiler/rustc_borrowck/src/type_check/liveness/trace.rs

@@ -258,7 +258,7 @@ impl<'me, 'typeck, 'flow, 'tcx> LivenessResults<'me, 'typeck, 'flow, 'tcx> {
 
                 let block = self.cx.elements.to_location(block_start).block;
                 self.stack.extend(
-                    self.cx.body.predecessors()[block]
+                    self.cx.body.basic_blocks.predecessors()[block]
                         .iter()
                         .map(|&pred_bb| self.cx.body.terminator_loc(pred_bb))
                         .map(|pred_loc| self.cx.elements.point_from_location(pred_loc)),
@@ -354,7 +354,7 @@ impl<'me, 'typeck, 'flow, 'tcx> LivenessResults<'me, 'typeck, 'flow, 'tcx> {
         }
 
         let body = self.cx.body;
-        for &pred_block in body.predecessors()[block].iter() {
+        for &pred_block in body.basic_blocks.predecessors()[block].iter() {
             debug!("compute_drop_live_points_for_block: pred_block = {:?}", pred_block,);
 
             // Check whether the variable is (at least partially)

compiler/rustc_codegen_ssa/src/mir/analyze.rs

@@ -15,7 +15,7 @@ pub fn non_ssa_locals<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>(
     fx: &FunctionCx<'a, 'tcx, Bx>,
 ) -> BitSet<mir::Local> {
     let mir = fx.mir;
-    let dominators = mir.dominators();
+    let dominators = mir.basic_blocks.dominators();
     let locals = mir
         .local_decls
         .iter()

compiler/rustc_const_eval/src/transform/promote_consts.rs

@@ -856,7 +856,8 @@ impl<'a, 'tcx> Promoter<'a, 'tcx> {
                     literal: ConstantKind::from_const(_const, tcx),
                 }))
             };
-            let (blocks, local_decls) = self.source.basic_blocks_and_local_decls_mut();
+            let blocks = self.source.basic_blocks.as_mut();
+            let local_decls = &mut self.source.local_decls;
             let loc = candidate.location;
             let statement = &mut blocks[loc.block].statements[loc.statement_index];
             match statement.kind {
@@ -865,7 +866,7 @@ impl<'a, 'tcx> Promoter<'a, 'tcx> {
                     Rvalue::Ref(ref mut region, borrow_kind, ref mut place),
                 )) => {
                     // Use the underlying local for this (necessarily interior) borrow.
-                    let ty = local_decls.local_decls()[place.local].ty;
+                    let ty = local_decls[place.local].ty;
                     let span = statement.source_info.span;
 
                     let ref_ty = tcx.mk_ref(

compiler/rustc_const_eval/src/transform/validate.rs

@@ -12,6 +12,7 @@ use rustc_middle::mir::{
     Statement, StatementKind, Terminator, TerminatorKind, UnOp, START_BLOCK,
 };
 use rustc_middle::ty::fold::BottomUpFolder;
+use rustc_middle::ty::subst::Subst;
 use rustc_middle::ty::{self, InstanceDef, ParamEnv, Ty, TyCtxt, TypeFoldable, TypeVisitable};
 use rustc_mir_dataflow::impls::MaybeStorageLive;
 use rustc_mir_dataflow::storage::always_live_locals;
@@ -275,7 +276,14 @@ impl<'a, 'tcx> Visitor<'tcx> for TypeChecker<'a, 'tcx> {
                     }
                 };
 
-                match parent_ty.ty.kind() {
+                let kind = match parent_ty.ty.kind() {
+                    &ty::Opaque(def_id, substs) => {
+                        self.tcx.bound_type_of(def_id).subst(self.tcx, substs).kind()
+                    }
+                    kind => kind,
+                };
+
+                match kind {
                     ty::Tuple(fields) => {
                         let Some(f_ty) = fields.get(f.as_usize()) else {
                             fail_out_of_bounds(self, location);
@@ -299,12 +307,39 @@ impl<'a, 'tcx> Visitor<'tcx> for TypeChecker<'a, 'tcx> {
                         };
                         check_equal(self, location, f_ty);
                     }
-                    ty::Generator(_, substs, _) => {
-                        let substs = substs.as_generator();
-                        let Some(f_ty) = substs.upvar_tys().nth(f.as_usize()) else {
-                            fail_out_of_bounds(self, location);
-                            return;
+                    &ty::Generator(def_id, substs, _) => {
+                        let f_ty = if let Some(var) = parent_ty.variant_index {
+                            let gen_body = if def_id == self.body.source.def_id() {
+                                self.body
+                            } else {
+                                self.tcx.optimized_mir(def_id)
+                            };
+
+                            let Some(layout) = gen_body.generator_layout() else {
+                                self.fail(location, format!("No generator layout for {:?}", parent_ty));
+                                return;
+                            };
+
+                            let Some(&local) = layout.variant_fields[var].get(f) else {
+                                fail_out_of_bounds(self, location);
+                                return;
+                            };
+
+                            let Some(&f_ty) = layout.field_tys.get(local) else {
+                                self.fail(location, format!("Out of bounds local {:?} for {:?}", local, parent_ty));
+                                return;
+                            };
+
+                            f_ty
+                        } else {
+                            let Some(f_ty) = substs.as_generator().prefix_tys().nth(f.index()) else {
+                                fail_out_of_bounds(self, location);
+                                return;
+                            };
+
+                            f_ty
                         };
+
                         check_equal(self, location, f_ty);
                     }
                     _ => {
@@ -328,6 +363,8 @@ impl<'a, 'tcx> Visitor<'tcx> for TypeChecker<'a, 'tcx> {
         {
             self.fail(location, format!("{:?}, has deref at the wrong place", place));
         }
+
+        self.super_place(place, cntxt, location);
     }
 
     fn visit_rvalue(&mut self, rvalue: &Rvalue<'tcx>, location: Location) {

compiler/rustc_lint/src/context.rs

@@ -34,7 +34,7 @@ use rustc_middle::middle::stability;
 use rustc_middle::ty::layout::{LayoutError, LayoutOfHelpers, TyAndLayout};
 use rustc_middle::ty::print::with_no_trimmed_paths;
 use rustc_middle::ty::{self, print::Printer, subst::GenericArg, RegisteredTools, Ty, TyCtxt};
-use rustc_session::lint::BuiltinLintDiagnostics;
+use rustc_session::lint::{BuiltinLintDiagnostics, LintExpectationId};
 use rustc_session::lint::{FutureIncompatibleInfo, Level, Lint, LintBuffer, LintId};
 use rustc_session::Session;
 use rustc_span::lev_distance::find_best_match_for_name;
@@ -906,6 +906,29 @@ pub trait LintContext: Sized {
     ) {
         self.lookup(lint, None as Option<Span>, decorate);
     }
+
+    /// This returns the lint level for the given lint at the current location.
+    fn get_lint_level(&self, lint: &'static Lint) -> Level;
+
+    /// This function can be used to manually fulfill an expectation. This can
+    /// be used for lints which contain several spans, and should be suppressed,
+    /// if either location was marked with an expectation.
+    ///
+    /// Note that this function should only be called for [`LintExpectationId`]s
+    /// retrieved from the current lint pass. Buffered or manually created ids can
+    /// cause ICEs.
+    fn fulfill_expectation(&self, expectation: LintExpectationId) {
+        // We need to make sure that submitted expectation ids are correctly fulfilled suppressed
+        // and stored between compilation sessions. To not manually do these steps, we simply create
+        // a dummy diagnostic and emit is as usual, which will be suppressed and stored like a normal
+        // expected lint diagnostic.
+        self.sess()
+            .struct_expect(
+                "this is a dummy diagnostic, to submit and store an expectation",
+                expectation,
+            )
+            .emit();
+    }
 }
 
 impl<'a> EarlyContext<'a> {
@@ -953,6 +976,10 @@ impl LintContext for LateContext<'_> {
             None => self.tcx.struct_lint_node(lint, hir_id, decorate),
         }
     }
+
+    fn get_lint_level(&self, lint: &'static Lint) -> Level {
+        self.tcx.lint_level_at_node(lint, self.last_node_with_lint_attrs).0
+    }
 }
 
 impl LintContext for EarlyContext<'_> {
@@ -975,6 +1002,10 @@ impl LintContext for EarlyContext<'_> {
     ) {
         self.builder.struct_lint(lint, span.map(|s| s.into()), decorate)
     }
+
+    fn get_lint_level(&self, lint: &'static Lint) -> Level {
+        self.builder.lint_level(lint).0
+    }
 }
 
 impl<'tcx> LateContext<'tcx> {

compiler/rustc_lint_defs/src/builtin.rs

@@ -520,6 +520,11 @@ declare_lint! {
     /// The `expect` attribute can be removed if this is intended behavior otherwise
     /// it should be investigated why the expected lint is no longer issued.
     ///
+    /// In rare cases, the expectation might be emitted at a different location than
+    /// shown in the shown code snippet. In most cases, the `#[expect]` attribute
+    /// works when added to the outer scope. A few lints can only be expected
+    /// on a crate level.
+    ///
     /// Part of RFC 2383. The progress is being tracked in [#54503]
     ///
     /// [#54503]: https://github.com/rust-lang/rust/issues/54503

compiler/rustc_lint_defs/src/lib.rs

@@ -232,6 +232,13 @@ impl Level {
             Level::Deny | Level::Forbid => true,
         }
     }
+
+    pub fn get_expectation_id(&self) -> Option<LintExpectationId> {
+        match self {
+            Level::Expect(id) | Level::ForceWarn(Some(id)) => Some(*id),
+            _ => None,
+        }
+    }
 }
 
 /// Specification of a single lint.