Rollup of 6 pull requests

compiler/rustc_const_eval/src/interpret/machine.rs

@@ -19,7 +19,7 @@ use rustc_target::spec::abi::Abi as CallAbi;
 use super::{
     throw_unsup, throw_unsup_format, AllocBytes, AllocId, AllocKind, AllocRange, Allocation,
     ConstAllocation, CtfeProvenance, FnArg, Frame, ImmTy, InterpCx, InterpResult, MPlaceTy,
-    MemoryKind, Misalignment, OpTy, PlaceTy, Pointer, Provenance,
+    MemoryKind, Misalignment, OpTy, PlaceTy, Pointer, Provenance, CTFE_ALLOC_SALT,
 };
 
 /// Data returned by [`Machine::after_stack_pop`], and consumed by
@@ -575,6 +575,14 @@ pub trait Machine<'tcx>: Sized {
     {
         eval(ecx, val, span, layout)
     }
+
+    /// Returns the salt to be used for a deduplicated global alloation.
+    /// If the allocation is for a function, the instance is provided as well
+    /// (this lets Miri ensure unique addresses for some functions).
+    fn get_global_alloc_salt(
+        ecx: &InterpCx<'tcx, Self>,
+        instance: Option<ty::Instance<'tcx>>,
+    ) -> usize;
 }
 
 /// A lot of the flexibility above is just needed for `Miri`, but all "compile-time" machines
@@ -677,4 +685,12 @@ pub macro compile_time_machine(<$tcx: lifetime>) {
         let (prov, offset) = ptr.into_parts();
         Some((prov.alloc_id(), offset, prov.immutable()))
     }
+
+    #[inline(always)]
+    fn get_global_alloc_salt(
+        _ecx: &InterpCx<$tcx, Self>,
+        _instance: Option<ty::Instance<$tcx>>,
+    ) -> usize {
+        CTFE_ALLOC_SALT
+    }
 }

compiler/rustc_const_eval/src/interpret/memory.rs

@@ -195,7 +195,10 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> {
 
     pub fn fn_ptr(&mut self, fn_val: FnVal<'tcx, M::ExtraFnVal>) -> Pointer<M::Provenance> {
         let id = match fn_val {
-            FnVal::Instance(instance) => self.tcx.reserve_and_set_fn_alloc(instance),
+            FnVal::Instance(instance) => {
+                let salt = M::get_global_alloc_salt(self, Some(instance));
+                self.tcx.reserve_and_set_fn_alloc(instance, salt)
+            }
             FnVal::Other(extra) => {
                 // FIXME(RalfJung): Should we have a cache here?
                 let id = self.tcx.reserve_alloc_id();

compiler/rustc_const_eval/src/interpret/place.rs

@@ -1008,7 +1008,8 @@ where
         // Use cache for immutable strings.
         let ptr = if mutbl.is_not() {
             // Use dedup'd allocation function.
-            let id = tcx.allocate_bytes_dedup(str.as_bytes());
+            let salt = M::get_global_alloc_salt(self, None);
+            let id = tcx.allocate_bytes_dedup(str.as_bytes(), salt);
 
             // Turn untagged "global" pointers (obtained via `tcx`) into the machine pointer to the allocation.
             M::adjust_alloc_root_pointer(&self, Pointer::from(id), Some(kind))?

compiler/rustc_const_eval/src/interpret/traits.rs

@@ -28,7 +28,9 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> {
         ensure_monomorphic_enough(*self.tcx, ty)?;
         ensure_monomorphic_enough(*self.tcx, poly_trait_ref)?;
 
-        let vtable_symbolic_allocation = self.tcx.reserve_and_set_vtable_alloc(ty, poly_trait_ref);
+        let salt = M::get_global_alloc_salt(self, None);
+        let vtable_symbolic_allocation =
+            self.tcx.reserve_and_set_vtable_alloc(ty, poly_trait_ref, salt);
         let vtable_ptr = self.global_root_pointer(Pointer::from(vtable_symbolic_allocation))?;
         Ok(vtable_ptr.into())
     }

compiler/rustc_data_structures/src/steal.rs

@@ -51,6 +51,15 @@ impl<T> Steal<T> {
         let value = value_ref.take();
         value.expect("attempt to steal from stolen value")
     }
+
+    /// Writers of rustc drivers often encounter stealing issues. This function makes it possible to
+    /// handle these errors gracefully.
+    ///
+    /// This should not be used within rustc as it leaks information not tracked
+    /// by the query system, breaking incremental compilation.
+    pub fn is_stolen(&self) -> bool {
+        self.value.borrow().is_none()
+    }
 }
 
 impl<CTX, T: HashStable<CTX>> HashStable<CTX> for Steal<T> {

compiler/rustc_hir_typeck/src/fn_ctxt/checks.rs

@@ -22,7 +22,7 @@ use rustc_middle::ty::{self, IsSuggestable, Ty, TyCtxt};
 use rustc_middle::{bug, span_bug};
 use rustc_session::Session;
 use rustc_span::symbol::{kw, Ident};
-use rustc_span::{sym, BytePos, Span, DUMMY_SP};
+use rustc_span::{sym, Span, DUMMY_SP};
 use rustc_trait_selection::error_reporting::infer::{FailureCode, ObligationCauseExt};
 use rustc_trait_selection::infer::InferCtxtExt;
 use rustc_trait_selection::traits::{self, ObligationCauseCode, SelectionContext};
@@ -1140,8 +1140,11 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                                 .get(arg_idx + 1)
                                 .map(|&(_, sp)| sp)
                                 .unwrap_or_else(|| {
-                                    // Subtract one to move before `)`
-                                    call_expr.span.with_lo(call_expr.span.hi() - BytePos(1))
+                                    // Try to move before `)`. Note that `)` here is not necessarily
+                                    // the latin right paren, it could be a Unicode-confusable that
+                                    // looks like a `)`, so we must not use `- BytePos(1)`
+                                    // manipulations here.
+                                    self.tcx().sess.source_map().end_point(call_expr.span)
                                 });
 
                             // Include next comma

compiler/rustc_middle/src/mir/interpret/mod.rs

@@ -13,7 +13,6 @@ use std::num::NonZero;
 use std::{fmt, io};
 
 use rustc_ast::LitKind;
-use rustc_attr::InlineAttr;
 use rustc_data_structures::fx::FxHashMap;
 use rustc_data_structures::sync::Lock;
 use rustc_errors::ErrorGuaranteed;
@@ -46,7 +45,7 @@ pub use self::pointer::{CtfeProvenance, Pointer, PointerArithmetic, Provenance};
 pub use self::value::Scalar;
 use crate::mir;
 use crate::ty::codec::{TyDecoder, TyEncoder};
-use crate::ty::{self, GenericArgKind, Instance, Ty, TyCtxt};
+use crate::ty::{self, Instance, Ty, TyCtxt};
 
 /// Uniquely identifies one of the following:
 /// - A constant
@@ -126,11 +125,10 @@ pub fn specialized_encode_alloc_id<'tcx, E: TyEncoder<I = TyCtxt<'tcx>>>(
             AllocDiscriminant::Alloc.encode(encoder);
             alloc.encode(encoder);
         }
-        GlobalAlloc::Function { instance, unique } => {
+        GlobalAlloc::Function { instance } => {
             trace!("encoding {:?} with {:#?}", alloc_id, instance);
             AllocDiscriminant::Fn.encode(encoder);
             instance.encode(encoder);
-            unique.encode(encoder);
         }
         GlobalAlloc::VTable(ty, poly_trait_ref) => {
             trace!("encoding {:?} with {ty:#?}, {poly_trait_ref:#?}", alloc_id);
@@ -219,38 +217,32 @@ impl<'s> AllocDecodingSession<'s> {
         }
 
         // Now decode the actual data.
-        let alloc_id = decoder.with_position(pos, |decoder| {
-            match alloc_kind {
-                AllocDiscriminant::Alloc => {
-                    trace!("creating memory alloc ID");
-                    let alloc = <ConstAllocation<'tcx> as Decodable<_>>::decode(decoder);
-                    trace!("decoded alloc {:?}", alloc);
-                    decoder.interner().reserve_and_set_memory_alloc(alloc)
-                }
-                AllocDiscriminant::Fn => {
-                    trace!("creating fn alloc ID");
-                    let instance = ty::Instance::decode(decoder);
-                    trace!("decoded fn alloc instance: {:?}", instance);
-                    let unique = bool::decode(decoder);
-                    // Here we cannot call `reserve_and_set_fn_alloc` as that would use a query, which
-                    // is not possible in this context. That's why the allocation stores
-                    // whether it is unique or not.
-                    decoder.interner().reserve_and_set_fn_alloc_internal(instance, unique)
-                }
-                AllocDiscriminant::VTable => {
-                    trace!("creating vtable alloc ID");
-                    let ty = <Ty<'_> as Decodable<D>>::decode(decoder);
-                    let poly_trait_ref =
-                        <Option<ty::PolyExistentialTraitRef<'_>> as Decodable<D>>::decode(decoder);
-                    trace!("decoded vtable alloc instance: {ty:?}, {poly_trait_ref:?}");
-                    decoder.interner().reserve_and_set_vtable_alloc(ty, poly_trait_ref)
-                }
-                AllocDiscriminant::Static => {
-                    trace!("creating extern static alloc ID");
-                    let did = <DefId as Decodable<D>>::decode(decoder);
-                    trace!("decoded static def-ID: {:?}", did);
-                    decoder.interner().reserve_and_set_static_alloc(did)
-                }
+        let alloc_id = decoder.with_position(pos, |decoder| match alloc_kind {
+            AllocDiscriminant::Alloc => {
+                trace!("creating memory alloc ID");
+                let alloc = <ConstAllocation<'tcx> as Decodable<_>>::decode(decoder);
+                trace!("decoded alloc {:?}", alloc);
+                decoder.interner().reserve_and_set_memory_alloc(alloc)
+            }
+            AllocDiscriminant::Fn => {
+                trace!("creating fn alloc ID");
+                let instance = ty::Instance::decode(decoder);
+                trace!("decoded fn alloc instance: {:?}", instance);
+                decoder.interner().reserve_and_set_fn_alloc(instance, CTFE_ALLOC_SALT)
+            }
+            AllocDiscriminant::VTable => {
+                trace!("creating vtable alloc ID");
+                let ty = <Ty<'_> as Decodable<D>>::decode(decoder);
+                let poly_trait_ref =
+                    <Option<ty::PolyExistentialTraitRef<'_>> as Decodable<D>>::decode(decoder);
+                trace!("decoded vtable alloc instance: {ty:?}, {poly_trait_ref:?}");
+                decoder.interner().reserve_and_set_vtable_alloc(ty, poly_trait_ref, CTFE_ALLOC_SALT)
+            }
+            AllocDiscriminant::Static => {
+                trace!("creating extern static alloc ID");
+                let did = <DefId as Decodable<D>>::decode(decoder);
+                trace!("decoded static def-ID: {:?}", did);
+                decoder.interner().reserve_and_set_static_alloc(did)
             }
         });
 
@@ -265,12 +257,7 @@ impl<'s> AllocDecodingSession<'s> {
 #[derive(Debug, Clone, Eq, PartialEq, Hash, TyDecodable, TyEncodable, HashStable)]
 pub enum GlobalAlloc<'tcx> {
     /// The alloc ID is used as a function pointer.
-    Function {
-        instance: Instance<'tcx>,
-        /// Stores whether this instance is unique, i.e. all pointers to this function use the same
-        /// alloc ID.
-        unique: bool,
-    },
+    Function { instance: Instance<'tcx> },
     /// This alloc ID points to a symbolic (not-reified) vtable.
     VTable(Ty<'tcx>, Option<ty::PolyExistentialTraitRef<'tcx>>),
     /// The alloc ID points to a "lazy" static variable that did not get computed (yet).
@@ -323,14 +310,17 @@ impl<'tcx> GlobalAlloc<'tcx> {
     }
 }
 
+pub const CTFE_ALLOC_SALT: usize = 0;
+
 pub(crate) struct AllocMap<'tcx> {
     /// Maps `AllocId`s to their corresponding allocations.
     alloc_map: FxHashMap<AllocId, GlobalAlloc<'tcx>>,
 
-    /// Used to ensure that statics and functions only get one associated `AllocId`.
-    //
-    // FIXME: Should we just have two separate dedup maps for statics and functions each?
-    dedup: FxHashMap<GlobalAlloc<'tcx>, AllocId>,
+    /// Used to deduplicate global allocations: functions, vtables, string literals, ...
+    ///
+    /// The `usize` is a "salt" used by Miri to make deduplication imperfect, thus better emulating
+    /// the actual guarantees.
+    dedup: FxHashMap<(GlobalAlloc<'tcx>, usize), AllocId>,
 
     /// The `AllocId` to assign to the next requested ID.
     /// Always incremented; never gets smaller.
@@ -368,83 +358,50 @@ impl<'tcx> TyCtxt<'tcx> {
 
     /// Reserves a new ID *if* this allocation has not been dedup-reserved before.
     /// Should not be used for mutable memory.
-    fn reserve_and_set_dedup(self, alloc: GlobalAlloc<'tcx>) -> AllocId {
+    fn reserve_and_set_dedup(self, alloc: GlobalAlloc<'tcx>, salt: usize) -> AllocId {
         let mut alloc_map = self.alloc_map.lock();
         if let GlobalAlloc::Memory(mem) = alloc {
             if mem.inner().mutability.is_mut() {
                 bug!("trying to dedup-reserve mutable memory");
             }
         }
-        if let Some(&alloc_id) = alloc_map.dedup.get(&alloc) {
+        let alloc_salt = (alloc, salt);
+        if let Some(&alloc_id) = alloc_map.dedup.get(&alloc_salt) {
             return alloc_id;
         }
         let id = alloc_map.reserve();
-        debug!("creating alloc {alloc:?} with id {id:?}");
-        alloc_map.alloc_map.insert(id, alloc.clone());
-        alloc_map.dedup.insert(alloc, id);
+        debug!("creating alloc {:?} with id {id:?}", alloc_salt.0);
+        alloc_map.alloc_map.insert(id, alloc_salt.0.clone());
+        alloc_map.dedup.insert(alloc_salt, id);
         id
     }
 
     /// Generates an `AllocId` for a memory allocation. If the exact same memory has been
     /// allocated before, this will return the same `AllocId`.
-    pub fn reserve_and_set_memory_dedup(self, mem: ConstAllocation<'tcx>) -> AllocId {
-        self.reserve_and_set_dedup(GlobalAlloc::Memory(mem))
+    pub fn reserve_and_set_memory_dedup(self, mem: ConstAllocation<'tcx>, salt: usize) -> AllocId {
+        self.reserve_and_set_dedup(GlobalAlloc::Memory(mem), salt)
     }
 
     /// Generates an `AllocId` for a static or return a cached one in case this function has been
     /// called on the same static before.
     pub fn reserve_and_set_static_alloc(self, static_id: DefId) -> AllocId {
-        self.reserve_and_set_dedup(GlobalAlloc::Static(static_id))
-    }
-
-    /// Generates an `AllocId` for a function. The caller must already have decided whether this
-    /// function obtains a unique AllocId or gets de-duplicated via the cache.
-    fn reserve_and_set_fn_alloc_internal(self, instance: Instance<'tcx>, unique: bool) -> AllocId {
-        let alloc = GlobalAlloc::Function { instance, unique };
-        if unique {
-            // Deduplicate.
-            self.reserve_and_set_dedup(alloc)
-        } else {
-            // Get a fresh ID.
-            let mut alloc_map = self.alloc_map.lock();
-            let id = alloc_map.reserve();
-            alloc_map.alloc_map.insert(id, alloc);
-            id
-        }
+        let salt = 0; // Statics have a guaranteed unique address, no salt added.
+        self.reserve_and_set_dedup(GlobalAlloc::Static(static_id), salt)
     }
 
-    /// Generates an `AllocId` for a function. Depending on the function type,
-    /// this might get deduplicated or assigned a new ID each time.
-    pub fn reserve_and_set_fn_alloc(self, instance: Instance<'tcx>) -> AllocId {
-        // Functions cannot be identified by pointers, as asm-equal functions can get deduplicated
-        // by the linker (we set the "unnamed_addr" attribute for LLVM) and functions can be
-        // duplicated across crates. We thus generate a new `AllocId` for every mention of a
-        // function. This means that `main as fn() == main as fn()` is false, while `let x = main as
-        // fn(); x == x` is true. However, as a quality-of-life feature it can be useful to identify
-        // certain functions uniquely, e.g. for backtraces. So we identify whether codegen will
-        // actually emit duplicate functions. It does that when they have non-lifetime generics, or
-        // when they can be inlined. All other functions are given a unique address.
-        // This is not a stable guarantee! The `inline` attribute is a hint and cannot be relied
-        // upon for anything. But if we don't do this, backtraces look terrible.
-        let is_generic = instance
-            .args
-            .into_iter()
-            .any(|kind| !matches!(kind.unpack(), GenericArgKind::Lifetime(_)));
-        let can_be_inlined = match self.codegen_fn_attrs(instance.def_id()).inline {
-            InlineAttr::Never => false,
-            _ => true,
-        };
-        let unique = !is_generic && !can_be_inlined;
-        self.reserve_and_set_fn_alloc_internal(instance, unique)
+    /// Generates an `AllocId` for a function. Will get deduplicated.
+    pub fn reserve_and_set_fn_alloc(self, instance: Instance<'tcx>, salt: usize) -> AllocId {
+        self.reserve_and_set_dedup(GlobalAlloc::Function { instance }, salt)
     }
 
     /// Generates an `AllocId` for a (symbolic, not-reified) vtable. Will get deduplicated.
     pub fn reserve_and_set_vtable_alloc(
         self,
         ty: Ty<'tcx>,
         poly_trait_ref: Option<ty::PolyExistentialTraitRef<'tcx>>,
+        salt: usize,
     ) -> AllocId {
-        self.reserve_and_set_dedup(GlobalAlloc::VTable(ty, poly_trait_ref))
+        self.reserve_and_set_dedup(GlobalAlloc::VTable(ty, poly_trait_ref), salt)
     }
 
     /// Interns the `Allocation` and return a new `AllocId`, even if there's already an identical

compiler/rustc_middle/src/ty/context.rs

@@ -1438,11 +1438,11 @@ impl<'tcx> TyCtxt<'tcx> {
 
     /// Allocates a read-only byte or string literal for `mir::interpret`.
     /// Returns the same `AllocId` if called again with the same bytes.
-    pub fn allocate_bytes_dedup(self, bytes: &[u8]) -> interpret::AllocId {
+    pub fn allocate_bytes_dedup(self, bytes: &[u8], salt: usize) -> interpret::AllocId {
         // Create an allocation that just contains these bytes.
         let alloc = interpret::Allocation::from_bytes_byte_aligned_immutable(bytes);
         let alloc = self.mk_const_alloc(alloc);
-        self.reserve_and_set_memory_dedup(alloc)
+        self.reserve_and_set_memory_dedup(alloc, salt)
     }
 
     /// Returns a range of the start/end indices specified with the

compiler/rustc_middle/src/ty/vtable.rs

@@ -3,7 +3,7 @@ use std::fmt;
 use rustc_ast::Mutability;
 use rustc_macros::HashStable;
 
-use crate::mir::interpret::{alloc_range, AllocId, Allocation, Pointer, Scalar};
+use crate::mir::interpret::{alloc_range, AllocId, Allocation, Pointer, Scalar, CTFE_ALLOC_SALT};
 use crate::ty::{self, Instance, PolyTraitRef, Ty, TyCtxt};
 
 #[derive(Clone, Copy, PartialEq, HashStable)]
@@ -73,6 +73,11 @@ pub(crate) fn vtable_min_entries<'tcx>(
 
 /// Retrieves an allocation that represents the contents of a vtable.
 /// Since this is a query, allocations are cached and not duplicated.
+///
+/// This is an "internal" `AllocId` that should never be used as a value in the interpreted program.
+/// The interpreter should use `AllocId` that refer to a `GlobalAlloc::VTable` instead.
+/// (This is similar to statics, which also have a similar "internal" `AllocId` storing their
+/// initial contents.)
 pub(super) fn vtable_allocation_provider<'tcx>(
     tcx: TyCtxt<'tcx>,
     key: (Ty<'tcx>, Option<ty::PolyExistentialTraitRef<'tcx>>),
@@ -114,7 +119,7 @@ pub(super) fn vtable_allocation_provider<'tcx>(
             VtblEntry::MetadataDropInPlace => {
                 if ty.needs_drop(tcx, ty::ParamEnv::reveal_all()) {
                     let instance = ty::Instance::resolve_drop_in_place(tcx, ty);
-                    let fn_alloc_id = tcx.reserve_and_set_fn_alloc(instance);
+                    let fn_alloc_id = tcx.reserve_and_set_fn_alloc(instance, CTFE_ALLOC_SALT);
                     let fn_ptr = Pointer::from(fn_alloc_id);
                     Scalar::from_pointer(fn_ptr, &tcx)
                 } else {
@@ -127,7 +132,7 @@ pub(super) fn vtable_allocation_provider<'tcx>(
             VtblEntry::Method(instance) => {
                 // Prepare the fn ptr we write into the vtable.
                 let instance = instance.polymorphize(tcx);
-                let fn_alloc_id = tcx.reserve_and_set_fn_alloc(instance);
+                let fn_alloc_id = tcx.reserve_and_set_fn_alloc(instance, CTFE_ALLOC_SALT);
                 let fn_ptr = Pointer::from(fn_alloc_id);
                 Scalar::from_pointer(fn_ptr, &tcx)
             }

compiler/rustc_mir_build/src/build/expr/as_constant.rs

@@ -2,7 +2,9 @@
 
 use rustc_ast as ast;
 use rustc_hir::LangItem;
-use rustc_middle::mir::interpret::{Allocation, LitToConstError, LitToConstInput, Scalar};
+use rustc_middle::mir::interpret::{
+    Allocation, LitToConstError, LitToConstInput, Scalar, CTFE_ALLOC_SALT,
+};
 use rustc_middle::mir::*;
 use rustc_middle::thir::*;
 use rustc_middle::ty::{
@@ -140,7 +142,7 @@ fn lit_to_mir_constant<'tcx>(
             ConstValue::Slice { data: allocation, meta: allocation.inner().size().bytes() }
         }
         (ast::LitKind::ByteStr(data, _), ty::Ref(_, inner_ty, _)) if inner_ty.is_array() => {
-            let id = tcx.allocate_bytes_dedup(data);
+            let id = tcx.allocate_bytes_dedup(data, CTFE_ALLOC_SALT);
             ConstValue::Scalar(Scalar::from_pointer(id.into(), &tcx))
         }
         (ast::LitKind::CStr(data, _), ty::Ref(_, inner_ty, _)) if matches!(inner_ty.kind(), ty::Adt(def, _) if tcx.is_lang_item(def.did(), LangItem::CStr)) =>

compiler/rustc_parse/src/parser/stmt.rs

@@ -408,10 +408,14 @@ impl<'a> Parser<'a> {
     fn parse_initializer(&mut self, eq_optional: bool) -> PResult<'a, Option<P<Expr>>> {
         let eq_consumed = match self.token.kind {
             token::BinOpEq(..) => {
-                // Recover `let x <op>= 1` as `let x = 1`
+                // Recover `let x <op>= 1` as `let x = 1` We must not use `+ BytePos(1)` here
+                // because `<op>` can be a multi-byte lookalike that was recovered, e.g. `➖=` (the
+                // `➖` is a U+2796 Heavy Minus Sign Unicode Character) that was recovered as a
+                // `-=`.
+                let extra_op_span = self.psess.source_map().start_point(self.token.span);
                 self.dcx().emit_err(errors::CompoundAssignmentExpressionInLet {
                     span: self.token.span,
-                    suggestion: self.token.span.with_hi(self.token.span.lo() + BytePos(1)),
+                    suggestion: extra_op_span,
                 });
                 self.bump();
                 true

library/std/src/sys/pal/unix/process/process_unix/tests.rs

@@ -24,7 +24,20 @@ fn exitstatus_display_tests() {
     // The purpose of this test is to test our string formatting, not our understanding of the wait
     // status magic numbers. So restrict these to Linux.
     if cfg!(target_os = "linux") {
+        #[cfg(any(target_arch = "mips", target_arch = "mips64"))]
+        t(0x0137f, "stopped (not terminated) by signal: 19 (SIGPWR)");
+
+        #[cfg(any(target_arch = "sparc", target_arch = "sparc64"))]
+        t(0x0137f, "stopped (not terminated) by signal: 19 (SIGCONT)");
+
+        #[cfg(not(any(
+            target_arch = "mips",
+            target_arch = "mips64",
+            target_arch = "sparc",
+            target_arch = "sparc64"
+        )))]
         t(0x0137f, "stopped (not terminated) by signal: 19 (SIGSTOP)");
+
         t(0x0ffff, "continued (WIFCONTINUED)");
     }
 

src/bootstrap/src/lib.rs

@@ -986,7 +986,8 @@ impl Build {
     }
 
     /// Execute a command and return its output.
-    /// This method should be used for all command executions in bootstrap.
+    /// Note: Ideally, you should use one of the BootstrapCommand::run* functions to
+    /// execute commands. They internally call this method.
     #[track_caller]
     fn run(
         &self,
@@ -1057,20 +1058,28 @@ Executed at: {executed_at}"#,
                 CommandOutput::did_not_start(stdout, stderr)
             }
         };
+
+        let fail = |message: &str| {
+            if self.is_verbose() {
+                println!("{message}");
+            } else {
+                println!("Command has failed. Rerun with -v to see more details.");
+            }
+            exit!(1);
+        };
+
         if !output.is_success() {
             match command.failure_behavior {
                 BehaviorOnFailure::DelayFail => {
                     if self.fail_fast {
-                        println!("{message}");
-                        exit!(1);
+                        fail(&message);
                     }
 
                     let mut failures = self.delayed_failures.borrow_mut();
                     failures.push(message);
                 }
                 BehaviorOnFailure::Exit => {
-                    println!("{message}");
-                    exit!(1);
+                    fail(&message);
                 }
                 BehaviorOnFailure::Ignore => {
                     // If failures are allowed, either the error has been printed already

src/tools/miri/src/lib.rs

@@ -56,6 +56,7 @@ extern crate either;
 extern crate tracing;
 
 // The rustc crates we need
+extern crate rustc_attr;
 extern crate rustc_apfloat;
 extern crate rustc_ast;
 extern crate rustc_const_eval;

src/tools/miri/src/machine.rs

@@ -11,6 +11,7 @@ use rand::rngs::StdRng;
 use rand::Rng;
 use rand::SeedableRng;
 
+use rustc_attr::InlineAttr;
 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
 #[allow(unused)]
 use rustc_data_structures::static_assert_size;
@@ -23,6 +24,7 @@ use rustc_middle::{
         Instance, Ty, TyCtxt,
     },
 };
+use rustc_session::config::InliningThreshold;
 use rustc_span::def_id::{CrateNum, DefId};
 use rustc_span::{Span, SpanData, Symbol};
 use rustc_target::abi::{Align, Size};
@@ -47,10 +49,10 @@ pub const SIGRTMIN: i32 = 34;
 /// `SIGRTMAX` - `SIGRTMIN` >= 8 (which is the value of `_POSIX_RTSIG_MAX`)
 pub const SIGRTMAX: i32 = 42;
 
-/// Each const has multiple addresses, but only this many. Since const allocations are never
-/// deallocated, choosing a new [`AllocId`] and thus base address for each evaluation would
-/// produce unbounded memory usage.
-const ADDRS_PER_CONST: usize = 16;
+/// Each anonymous global (constant, vtable, function pointer, ...) has multiple addresses, but only
+/// this many. Since const allocations are never deallocated, choosing a new [`AllocId`] and thus
+/// base address for each evaluation would produce unbounded memory usage.
+const ADDRS_PER_ANON_GLOBAL: usize = 32;
 
 /// Extra data stored with each stack frame
 pub struct FrameExtra<'tcx> {
@@ -1372,7 +1374,7 @@ impl<'tcx> Machine<'tcx> for MiriMachine<'tcx> {
             catch_unwind: None,
             timing,
             is_user_relevant: ecx.machine.is_user_relevant(&frame),
-            salt: ecx.machine.rng.borrow_mut().gen::<usize>() % ADDRS_PER_CONST,
+            salt: ecx.machine.rng.borrow_mut().gen::<usize>() % ADDRS_PER_ANON_GLOBAL,
         };
 
         Ok(frame.with_extra(extra))
@@ -1518,4 +1520,45 @@ impl<'tcx> Machine<'tcx> for MiriMachine<'tcx> {
             Entry::Occupied(oe) => Ok(oe.get().clone()),
         }
     }
+
+    fn get_global_alloc_salt(
+        ecx: &InterpCx<'tcx, Self>,
+        instance: Option<ty::Instance<'tcx>>,
+    ) -> usize {
+        let unique = if let Some(instance) = instance {
+            // Functions cannot be identified by pointers, as asm-equal functions can get
+            // deduplicated by the linker (we set the "unnamed_addr" attribute for LLVM) and
+            // functions can be duplicated across crates. We thus generate a new `AllocId` for every
+            // mention of a function. This means that `main as fn() == main as fn()` is false, while
+            // `let x = main as fn(); x == x` is true. However, as a quality-of-life feature it can
+            // be useful to identify certain functions uniquely, e.g. for backtraces. So we identify
+            // whether codegen will actually emit duplicate functions. It does that when they have
+            // non-lifetime generics, or when they can be inlined. All other functions are given a
+            // unique address. This is not a stable guarantee! The `inline` attribute is a hint and
+            // cannot be relied upon for anything. But if we don't do this, the
+            // `__rust_begin_short_backtrace`/`__rust_end_short_backtrace` logic breaks and panic
+            // backtraces look terrible.
+            let is_generic = instance
+                .args
+                .into_iter()
+                .any(|kind| !matches!(kind.unpack(), ty::GenericArgKind::Lifetime(_)));
+            let can_be_inlined = matches!(
+                ecx.tcx.sess.opts.unstable_opts.cross_crate_inline_threshold,
+                InliningThreshold::Always
+            ) || !matches!(
+                ecx.tcx.codegen_fn_attrs(instance.def_id()).inline,
+                InlineAttr::Never
+            );
+            !is_generic && !can_be_inlined
+        } else {
+            // Non-functions are never unique.
+            false
+        };
+        // Always use the same salt if the allocation is unique.
+        if unique {
+            CTFE_ALLOC_SALT
+        } else {
+            ecx.machine.rng.borrow_mut().gen::<usize>() % ADDRS_PER_ANON_GLOBAL
+        }
+    }
 }

src/tools/miri/tests/pass/dyn-traits.rs

@@ -141,7 +141,17 @@ fn unsized_dyn_autoderef() {
 }
 */
 
+fn vtable_ptr_eq() {
+    use std::{fmt, ptr};
+
+    // We don't always get the same vtable when casting this to a wide pointer.
+    let x = &2;
+    let x_wide = x as &dyn fmt::Display;
+    assert!((0..256).any(|_| !ptr::eq(x as &dyn fmt::Display, x_wide)));
+}
+
 fn main() {
     ref_box_dyn();
     box_box_trait();
+    vtable_ptr_eq();
 }

src/tools/miri/tests/pass/function_pointers.rs

@@ -82,7 +82,8 @@ fn main() {
     assert!(return_fn_ptr(i) == i);
     assert!(return_fn_ptr(i) as unsafe fn() -> i32 == i as fn() -> i32 as unsafe fn() -> i32);
     // Miri gives different addresses to different reifications of a generic function.
-    assert!(return_fn_ptr(f) != f);
+    // at least if we try often enough.
+    assert!((0..256).any(|_| return_fn_ptr(f) != f));
     // However, if we only turn `f` into a function pointer and use that pointer,
     // it is equal to itself.
     let f2 = f as fn() -> i32;

src/tools/miri/tests/pass/rc.rs

@@ -75,7 +75,8 @@ fn rc_fat_ptr_eq() {
     let p = Rc::new(1) as Rc<dyn Debug>;
     let a: *const dyn Debug = &*p;
     let r = Rc::into_raw(p);
-    assert!(a == r);
+    // Only compare the pointer parts, as the vtable might differ.
+    assert!(a as *const () == r as *const ());
     drop(unsafe { Rc::from_raw(r) });
 }
 

tests/ui/parser/suggest-remove-compount-assign-let-ice.rs

@@ -0,0 +1,16 @@
+//! Previously we would try to issue a suggestion for `let x <op>= 1`, i.e. a compound assignment
+//! within a `let` binding, to remove the `<op>`. The suggestion code unfortunately incorrectly
+//! assumed that the `<op>` is an exactly-1-byte ASCII character, but this assumption is incorrect
+//! because we also recover Unicode-confusables like `➖=` as `-=`. In this example, the suggestion
+//! code used a `+ BytePos(1)` to calculate the span of the `<op>` codepoint that looks like `-` but
+//! the mult-byte Unicode look-alike would cause the suggested removal span to be inside a
+//! multi-byte codepoint boundary, triggering a codepoint boundary assertion.
+//!
+//! issue: rust-lang/rust#128845
+
+fn main() {
+    // Adapted from #128845 but with irrelevant components removed and simplified.
+    let x ➖= 1;
+    //~^ ERROR unknown start of token: \u{2796}
+    //~| ERROR: can't reassign to an uninitialized variable
+}

tests/ui/parser/suggest-remove-compount-assign-let-ice.stderr

@@ -0,0 +1,26 @@
+error: unknown start of token: \u{2796}
+  --> $DIR/suggest-remove-compount-assign-let-ice.rs:13:11
+   |
+LL |     let x ➖= 1;
+   |           ^^
+   |
+help: Unicode character '➖' (Heavy Minus Sign) looks like '-' (Minus/Hyphen), but it is not
+   |
+LL |     let x -= 1;
+   |           ~
+
+error: can't reassign to an uninitialized variable
+  --> $DIR/suggest-remove-compount-assign-let-ice.rs:13:11
+   |
+LL |     let x ➖= 1;
+   |           ^^^
+   |
+   = help: if you meant to overwrite, remove the `let` binding
+help: initialize the variable
+   |
+LL -     let x ➖= 1;
+LL +     let x = 1;
+   |
+
+error: aborting due to 2 previous errors
+

tests/ui/typeck/suggest-arg-comma-delete-ice.rs

@@ -0,0 +1,19 @@
+//! Previously, we tried to remove extra arg commas when providing extra arg removal suggestions.
+//! One of the edge cases is having to account for an arg that has a closing delimiter `)`
+//! following it. However, the previous suggestion code assumed that the delimiter is in fact
+//! exactly the 1-byte `)` character. This assumption was proven incorrect, because we recover
+//! from Unicode-confusable delimiters in the parser, which means that the ending delimiter could be
+//! a multi-byte codepoint that looks *like* a `)`. Subtracing 1 byte could land us in the middle of
+//! a codepoint, triggering a codepoint boundary assertion.
+//!
+//! issue: rust-lang/rust#128717
+
+fn main() {
+    // The following example has been modified from #128717 to remove irrelevant Unicode as they do
+    // not otherwise partake in the right delimiter calculation causing the codepoint boundary
+    // assertion.
+    main(rahh）;
+    //~^ ERROR unknown start of token
+    //~| ERROR this function takes 0 arguments but 1 argument was supplied
+    //~| ERROR cannot find value `rahh` in this scope
+}

tests/ui/typeck/suggest-arg-comma-delete-ice.stderr

@@ -0,0 +1,38 @@
+error: unknown start of token: \u{ff09}
+  --> $DIR/suggest-arg-comma-delete-ice.rs:15:14
+   |
+LL |     main(rahh）;
+   |              ^^
+   |
+help: Unicode character '）' (Fullwidth Right Parenthesis) looks like ')' (Right Parenthesis), but it is not
+   |
+LL |     main(rahh);
+   |              ~
+
+error[E0425]: cannot find value `rahh` in this scope
+  --> $DIR/suggest-arg-comma-delete-ice.rs:15:10
+   |
+LL |     main(rahh）;
+   |          ^^^^ not found in this scope
+
+error[E0061]: this function takes 0 arguments but 1 argument was supplied
+  --> $DIR/suggest-arg-comma-delete-ice.rs:15:5
+   |
+LL |     main(rahh）;
+   |     ^^^^ ---- unexpected argument
+   |
+note: function defined here
+  --> $DIR/suggest-arg-comma-delete-ice.rs:11:4
+   |
+LL | fn main() {
+   |    ^^^^
+help: remove the extra argument
+   |
+LL -     main(rahh）;
+LL +     main(）;
+   |
+
+error: aborting due to 3 previous errors
+
+Some errors have detailed explanations: E0061, E0425.
+For more information about an error, try `rustc --explain E0061`.