Rollup of 8 pull requests

compiler/rustc_codegen_cranelift/src/abi/mod.rs

@@ -467,7 +467,7 @@ pub(crate) fn codegen_terminator_call<'tcx>(
         true
     } else {
         instance.is_some_and(|inst| {
-            fx.tcx.codegen_fn_attrs(inst.def_id()).flags.contains(CodegenFnAttrFlags::COLD)
+            fx.tcx.codegen_instance_attrs(inst.def).flags.contains(CodegenFnAttrFlags::COLD)
         })
     };
     if is_cold {

compiler/rustc_codegen_ssa/src/mir/block.rs

@@ -200,10 +200,11 @@ impl<'a, 'tcx> TerminatorCodegenHelper<'tcx> {
         let fn_ty = bx.fn_decl_backend_type(fn_abi);
 
         let fn_attrs = if bx.tcx().def_kind(fx.instance.def_id()).has_codegen_attrs() {
-            Some(bx.tcx().codegen_fn_attrs(fx.instance.def_id()))
+            Some(bx.tcx().codegen_instance_attrs(fx.instance.def))
         } else {
             None
         };
+        let fn_attrs = fn_attrs.as_deref();
 
         if !fn_abi.can_unwind {
             unwind = mir::UnwindAction::Unreachable;

compiler/rustc_const_eval/src/check_consts/qualifs.rs

@@ -234,7 +234,7 @@ where
 
         Rvalue::Discriminant(place) => in_place::<Q, _>(cx, in_local, place.as_ref()),
 
-        Rvalue::CopyForDeref(_) => bug!("`CopyForDeref` in runtime MIR"),
+        Rvalue::CopyForDeref(place) => in_place::<Q, _>(cx, in_local, place.as_ref()),
 
         Rvalue::Use(operand)
         | Rvalue::Repeat(operand, _)

compiler/rustc_middle/src/middle/codegen_fn_attrs.rs

@@ -13,6 +13,8 @@ impl<'tcx> TyCtxt<'tcx> {
         self,
         instance_kind: InstanceKind<'_>,
     ) -> Cow<'tcx, CodegenFnAttrs> {
+        // NOTE: we try to not clone the `CodegenFnAttrs` when that is not needed.
+        // The `to_mut` method used below clones the inner value.
         let mut attrs = Cow::Borrowed(self.codegen_fn_attrs(instance_kind.def_id()));
 
         // Drop the `#[naked]` attribute on non-item `InstanceKind`s, like the shims that
@@ -23,6 +25,28 @@ impl<'tcx> TyCtxt<'tcx> {
             }
         }
 
+        // A shim created by `#[track_caller]` should not inherit any attributes
+        // that modify the symbol name. Failing to remove these attributes from
+        // the shim leads to errors like `symbol `foo` is already defined`.
+        //
+        // A `ClosureOnceShim` with the track_caller attribute does not have a symbol,
+        // and therefore can be skipped here.
+        if let InstanceKind::ReifyShim(_, _) = instance_kind
+            && attrs.flags.contains(CodegenFnAttrFlags::TRACK_CALLER)
+        {
+            if attrs.flags.contains(CodegenFnAttrFlags::NO_MANGLE) {
+                attrs.to_mut().flags.remove(CodegenFnAttrFlags::NO_MANGLE);
+            }
+
+            if attrs.flags.contains(CodegenFnAttrFlags::RUSTC_STD_INTERNAL_SYMBOL) {
+                attrs.to_mut().flags.remove(CodegenFnAttrFlags::RUSTC_STD_INTERNAL_SYMBOL);
+            }
+
+            if attrs.symbol_name.is_some() {
+                attrs.to_mut().symbol_name = None;
+            }
+        }
+
         attrs
     }
 }

compiler/rustc_mir_transform/src/inline.rs

@@ -245,7 +245,7 @@ impl<'tcx> Inliner<'tcx> for ForceInliner<'tcx> {
     fn on_inline_failure(&self, callsite: &CallSite<'tcx>, reason: &'static str) {
         let tcx = self.tcx();
         let InlineAttr::Force { attr_span, reason: justification } =
-            tcx.codegen_fn_attrs(callsite.callee.def_id()).inline
+            tcx.codegen_instance_attrs(callsite.callee.def).inline
         else {
             bug!("called on item without required inlining");
         };
@@ -603,7 +603,8 @@ fn try_inlining<'tcx, I: Inliner<'tcx>>(
     let tcx = inliner.tcx();
     check_mir_is_available(inliner, caller_body, callsite.callee)?;
 
-    let callee_attrs = tcx.codegen_fn_attrs(callsite.callee.def_id());
+    let callee_attrs = tcx.codegen_instance_attrs(callsite.callee.def);
+    let callee_attrs = callee_attrs.as_ref();
     check_inline::is_inline_valid_on_fn(tcx, callsite.callee.def_id())?;
     check_codegen_attributes(inliner, callsite, callee_attrs)?;
     inliner.check_codegen_attributes_extra(callee_attrs)?;

compiler/rustc_resolve/src/build_reduced_graph.rs

@@ -77,6 +77,7 @@ impl<'ra, 'tcx> Resolver<'ra, 'tcx> {
         parent: Module<'ra>,
         ident: Ident,
         ns: Namespace,
+        child_index: usize,
         res: Res,
         vis: Visibility<DefId>,
         span: Span,
@@ -86,10 +87,8 @@ impl<'ra, 'tcx> Resolver<'ra, 'tcx> {
         // Even if underscore names cannot be looked up, we still need to add them to modules,
         // because they can be fetched by glob imports from those modules, and bring traits
         // into scope both directly and through glob imports.
-        let key = BindingKey::new_disambiguated(ident, ns, || {
-            parent.underscore_disambiguator.update_unchecked(|d| d + 1);
-            parent.underscore_disambiguator.get()
-        });
+        let key =
+            BindingKey::new_disambiguated(ident, ns, || (child_index + 1).try_into().unwrap()); // 0 indicates no underscore
         if self
             .resolution_or_default(parent, key)
             .borrow_mut_unchecked()
@@ -233,9 +232,9 @@ impl<'ra, 'tcx> Resolver<'ra, 'tcx> {
     }
 
     pub(crate) fn build_reduced_graph_external(&self, module: Module<'ra>) {
-        for child in self.tcx.module_children(module.def_id()) {
+        for (i, child) in self.tcx.module_children(module.def_id()).into_iter().enumerate() {
             let parent_scope = ParentScope::module(module, self.arenas);
-            self.build_reduced_graph_for_external_crate_res(child, parent_scope)
+            self.build_reduced_graph_for_external_crate_res(child, parent_scope, i)
         }
     }
 
@@ -244,6 +243,7 @@ impl<'ra, 'tcx> Resolver<'ra, 'tcx> {
         &self,
         child: &ModChild,
         parent_scope: ParentScope<'ra>,
+        child_index: usize,
     ) {
         let parent = parent_scope.module;
         let ModChild { ident, res, vis, ref reexport_chain } = *child;
@@ -272,7 +272,9 @@ impl<'ra, 'tcx> Resolver<'ra, 'tcx> {
                 _,
             )
             | Res::PrimTy(..)
-            | Res::ToolMod => self.define_extern(parent, ident, TypeNS, res, vis, span, expansion),
+            | Res::ToolMod => {
+                self.define_extern(parent, ident, TypeNS, child_index, res, vis, span, expansion)
+            }
             Res::Def(
                 DefKind::Fn
                 | DefKind::AssocFn
@@ -281,9 +283,9 @@ impl<'ra, 'tcx> Resolver<'ra, 'tcx> {
                 | DefKind::AssocConst
                 | DefKind::Ctor(..),
                 _,
-            ) => self.define_extern(parent, ident, ValueNS, res, vis, span, expansion),
+            ) => self.define_extern(parent, ident, ValueNS, child_index, res, vis, span, expansion),
             Res::Def(DefKind::Macro(..), _) | Res::NonMacroAttr(..) => {
-                self.define_extern(parent, ident, MacroNS, res, vis, span, expansion)
+                self.define_extern(parent, ident, MacroNS, child_index, res, vis, span, expansion)
             }
             Res::Def(
                 DefKind::TyParam

compiler/rustc_target/src/spec/base/nto_qnx.rs

@@ -12,6 +12,9 @@ pub(crate) fn opts() -> TargetOptions {
         has_thread_local: false,
         linker: Some("qcc".into()),
         os: "nto".into(),
+        // We want backtraces to work by default and they rely on unwind tables
+        // (regardless of `-C panic` strategy).
+        default_uwtable: true,
         position_independent_executables: true,
         static_position_independent_executables: true,
         relro_level: RelroLevel::Full,

library/alloc/src/wtf8/tests.rs

@@ -579,6 +579,17 @@ fn wtf8_encode_wide_size_hint() {
     assert!(iter.next().is_none());
 }
 
+#[test]
+fn wtf8_encode_wide_debug() {
+    let mut string = Wtf8Buf::from_str("aé ");
+    string.push(CodePoint::from_u32(0xD83D).unwrap());
+    string.push_char('💩');
+    assert_eq!(
+        format!("{:?}", string.encode_wide()),
+        r#"EncodeWide(['a', 'é', ' ', 0xD83D, 0xD83D, 0xDCA9])"#
+    );
+}
+
 #[test]
 fn wtf8_clone_into() {
     let mut string = Wtf8Buf::new();

library/core/src/iter/sources/repeat.rs

@@ -101,8 +101,9 @@ impl<A: Clone> Iterator for Repeat<A> {
         Some(self.element.clone())
     }
 
+    #[track_caller]
     fn last(self) -> Option<A> {
-        Some(self.element)
+        panic!("iterator is infinite");
     }
 
     #[track_caller]

library/core/src/wtf8.rs

@@ -562,15 +562,36 @@ impl Iterator for EncodeWide<'_> {
     }
 }
 
+#[stable(feature = "encode_wide_fused_iterator", since = "1.62.0")]
+impl FusedIterator for EncodeWide<'_> {}
+
+#[stable(feature = "encode_wide_debug", since = "CURRENT_RUSTC_VERSION")]
 impl fmt::Debug for EncodeWide<'_> {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        f.debug_struct("EncodeWide").finish_non_exhaustive()
+        struct CodeUnit(u16);
+        impl fmt::Debug for CodeUnit {
+            fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+                // This output attempts to balance readability with precision.
+                // Render characters which take only one WTF-16 code unit using
+                // `char` syntax and everything else as code units with hex
+                // integer syntax (including paired and unpaired surrogate
+                // halves). Since Rust has no `char`-like type for WTF-16, this
+                // isn't perfect, so if this output isn't suitable, it is open
+                // to being changed (see #140153).
+                match char::from_u32(self.0 as u32) {
+                    Some(c) => write!(f, "{c:?}"),
+                    None => write!(f, "0x{:04X}", self.0),
+                }
+            }
+        }
+
+        write!(f, "EncodeWide(")?;
+        f.debug_list().entries(self.clone().map(CodeUnit)).finish()?;
+        write!(f, ")")?;
+        Ok(())
     }
 }
 
-#[stable(feature = "encode_wide_fused_iterator", since = "1.62.0")]
-impl FusedIterator for EncodeWide<'_> {}
-
 impl Hash for CodePoint {
     #[inline]
     fn hash<H: Hasher>(&self, state: &mut H) {

library/coretests/tests/iter/sources.rs

@@ -37,6 +37,7 @@ fn test_repeat_count() {
 }
 
 #[test]
+#[should_panic = "iterator is infinite"]
 fn test_repeat_last() {
     assert_eq!(repeat(42).last(), Some(42));
 }

library/std/src/fs.rs

@@ -387,6 +387,87 @@ pub fn write<P: AsRef<Path>, C: AsRef<[u8]>>(path: P, contents: C) -> io::Result
     inner(path.as_ref(), contents.as_ref())
 }
 
+/// Changes the timestamps of the file or directory at the specified path.
+///
+/// This function will attempt to set the access and modification times
+/// to the times specified. If the path refers to a symbolic link, this function
+/// will follow the link and change the timestamps of the target file.
+///
+/// # Platform-specific behavior
+///
+/// This function currently corresponds to the `utimensat` function on Unix platforms, the
+/// `setattrlist` function on Apple platforms, and the `SetFileTime` function on Windows.
+///
+/// # Errors
+///
+/// This function will return an error if the user lacks permission to change timestamps on the
+/// target file or symlink. It may also return an error if the OS does not support it.
+///
+/// # Examples
+///
+/// ```no_run
+/// #![feature(fs_set_times)]
+/// use std::fs::{self, FileTimes};
+/// use std::time::SystemTime;
+///
+/// fn main() -> std::io::Result<()> {
+///     let now = SystemTime::now();
+///     let times = FileTimes::new()
+///         .set_accessed(now)
+///         .set_modified(now);
+///     fs::set_times("foo.txt", times)?;
+///     Ok(())
+/// }
+/// ```
+#[unstable(feature = "fs_set_times", issue = "147455")]
+#[doc(alias = "utimens")]
+#[doc(alias = "utimes")]
+#[doc(alias = "utime")]
+pub fn set_times<P: AsRef<Path>>(path: P, times: FileTimes) -> io::Result<()> {
+    fs_imp::set_times(path.as_ref(), times.0)
+}
+
+/// Changes the timestamps of the file or symlink at the specified path.
+///
+/// This function will attempt to set the access and modification times
+/// to the times specified. Differ from `set_times`, if the path refers to a symbolic link,
+/// this function will change the timestamps of the symlink itself, not the target file.
+///
+/// # Platform-specific behavior
+///
+/// This function currently corresponds to the `utimensat` function with `AT_SYMLINK_NOFOLLOW` on
+/// Unix platforms, the `setattrlist` function with `FSOPT_NOFOLLOW` on Apple platforms, and the
+/// `SetFileTime` function on Windows.
+///
+/// # Errors
+///
+/// This function will return an error if the user lacks permission to change timestamps on the
+/// target file or symlink. It may also return an error if the OS does not support it.
+///
+/// # Examples
+///
+/// ```no_run
+/// #![feature(fs_set_times)]
+/// use std::fs::{self, FileTimes};
+/// use std::time::SystemTime;
+///
+/// fn main() -> std::io::Result<()> {
+///     let now = SystemTime::now();
+///     let times = FileTimes::new()
+///         .set_accessed(now)
+///         .set_modified(now);
+///     fs::set_times_nofollow("symlink.txt", times)?;
+///     Ok(())
+/// }
+/// ```
+#[unstable(feature = "fs_set_times", issue = "147455")]
+#[doc(alias = "utimensat")]
+#[doc(alias = "lutimens")]
+#[doc(alias = "lutimes")]
+pub fn set_times_nofollow<P: AsRef<Path>>(path: P, times: FileTimes) -> io::Result<()> {
+    fs_imp::set_times_nofollow(path.as_ref(), times.0)
+}
+
 #[stable(feature = "file_lock", since = "1.89.0")]
 impl error::Error for TryLockError {}