Merge branch 'master' into enzyme-backend

Author: ZuseZ4

.github/workflows/dependencies.yml

@@ -67,7 +67,7 @@ jobs:
       - name: cargo update rustbook
         run: |
           echo -e "\nrustbook dependencies:" >> cargo_update.log
-          cargo update --manifest-path src/tools/rustbook 2>&1 | sed '/crates.io index/d' | tee -a cargo_update.log
+          cargo update --manifest-path src/tools/rustbook/Cargo.toml 2>&1 | sed '/crates.io index/d' | tee -a cargo_update.log
       - name: upload Cargo.lock artifact for use in PR
         uses: actions/upload-artifact@v4
         with:

Cargo.lock

@@ -1775,9 +1775,9 @@ checksum = "ce23b50ad8242c51a442f3ff322d56b02f08852c77e4c0b4d3fd684abc89c683"
 
 [[package]]
 name = "indexmap"
-version = "2.2.6"
+version = "2.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "168fb715dda47215e360912c096649d23d58bf392ac62f73919e831745e40f26"
+checksum = "93ead53efc7ea8ed3cfb0c79fc8023fbb782a5432b52830b6518941cebe6505c"
 dependencies = [
  "equivalent",
  "hashbrown",
@@ -3149,6 +3149,7 @@ dependencies = [
  "gimli 0.31.0",
  "object 0.36.2",
  "regex",
+ "serde_json",
  "similar",
  "wasmparser 0.214.0",
 ]

compiler/rustc/src/main.rs

@@ -1,3 +1,6 @@
+// We need this feature as it changes `dylib` linking behavior and allows us to link to `rustc_driver`.
+#![feature(rustc_private)]
+
 // A note about jemalloc: rustc uses jemalloc when built for CI and
 // distribution. The obvious way to do this is with the `#[global_allocator]`
 // mechanism. However, for complicated reasons (see

compiler/rustc_ast/src/ast.rs

@@ -585,7 +585,9 @@ impl Pat {
             }
             // A slice/array pattern `[P]` can be reparsed as `[T]`, an unsized array,
             // when `P` can be reparsed as a type `T`.
-            PatKind::Slice(pats) if pats.len() == 1 => pats[0].to_ty().map(TyKind::Slice)?,
+            PatKind::Slice(pats) if let [pat] = pats.as_slice() => {
+                pat.to_ty().map(TyKind::Slice)?
+            }
             // A tuple pattern `(P0, .., Pn)` can be reparsed as `(T0, .., Tn)`
             // assuming `T0` to `Tn` are all syntactically valid as types.
             PatKind::Tuple(pats) => {
@@ -1187,8 +1189,8 @@ impl Expr {
     /// Does not ensure that the path resolves to a const param, the caller should check this.
     pub fn is_potential_trivial_const_arg(&self) -> bool {
         let this = if let ExprKind::Block(block, None) = &self.kind
-            && block.stmts.len() == 1
-            && let StmtKind::Expr(expr) = &block.stmts[0].kind
+            && let [stmt] = block.stmts.as_slice()
+            && let StmtKind::Expr(expr) = &stmt.kind
         {
             expr
         } else {
@@ -1248,7 +1250,9 @@ impl Expr {
                 expr.to_ty().map(|ty| TyKind::Array(ty, expr_len.clone()))?
             }
 
-            ExprKind::Array(exprs) if exprs.len() == 1 => exprs[0].to_ty().map(TyKind::Slice)?,
+            ExprKind::Array(exprs) if let [expr] = exprs.as_slice() => {
+                expr.to_ty().map(TyKind::Slice)?
+            }
 
             ExprKind::Tup(exprs) => {
                 let tys = exprs.iter().map(|expr| expr.to_ty()).collect::<Option<ThinVec<_>>>()?;

compiler/rustc_ast_lowering/messages.ftl

@@ -167,11 +167,21 @@ ast_lowering_template_modifier = template modifier
 
 ast_lowering_this_not_async = this is not `async`
 
+ast_lowering_underscore_array_length_unstable =
+    using `_` for array lengths is unstable
+
 ast_lowering_underscore_expr_lhs_assign =
     in expressions, `_` can only be used on the left-hand side of an assignment
     .label = `_` not allowed here
 
+ast_lowering_unstable_inline_assembly = inline assembly is not stable yet on this architecture
+ast_lowering_unstable_inline_assembly_label_operands =
+    label operands for inline assembly are unstable
+ast_lowering_unstable_may_unwind = the `may_unwind` option is unstable
+
 ast_lowering_use_angle_brackets = use angle brackets instead
+
+ast_lowering_yield = yield syntax is experimental
 ast_lowering_yield_in_closure =
     `yield` can only be used in `#[coroutine]` closures, or `gen` blocks
     .suggestion = use `#[coroutine]` to make this closure a coroutine

compiler/rustc_ast_lowering/src/asm.rs

@@ -19,10 +19,12 @@ use super::errors::{
     InvalidRegisterClass, RegisterClassOnlyClobber, RegisterConflict,
 };
 use super::LoweringContext;
-use crate::{ImplTraitContext, ImplTraitPosition, ParamMode, ResolverAstLoweringExt};
+use crate::{
+    fluent_generated as fluent, ImplTraitContext, ImplTraitPosition, ParamMode,
+    ResolverAstLoweringExt,
+};
 
 impl<'a, 'hir> LoweringContext<'a, 'hir> {
-    #[allow(rustc::untranslatable_diagnostic)] // FIXME: make this translatable
     pub(crate) fn lower_inline_asm(
         &mut self,
         sp: Span,
@@ -52,7 +54,7 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
                     &self.tcx.sess,
                     sym::asm_experimental_arch,
                     sp,
-                    "inline assembly is not stable yet on this architecture",
+                    fluent::ast_lowering_unstable_inline_assembly,
                 )
                 .emit();
             }
@@ -64,8 +66,13 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
             self.dcx().emit_err(AttSyntaxOnlyX86 { span: sp });
         }
         if asm.options.contains(InlineAsmOptions::MAY_UNWIND) && !self.tcx.features().asm_unwind {
-            feature_err(&self.tcx.sess, sym::asm_unwind, sp, "the `may_unwind` option is unstable")
-                .emit();
+            feature_err(
+                &self.tcx.sess,
+                sym::asm_unwind,
+                sp,
+                fluent::ast_lowering_unstable_may_unwind,
+            )
+            .emit();
         }
 
         let mut clobber_abis = FxIndexMap::default();
@@ -176,20 +183,9 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
                             out_expr: out_expr.as_ref().map(|expr| self.lower_expr(expr)),
                         }
                     }
-                    InlineAsmOperand::Const { anon_const } => {
-                        if !self.tcx.features().asm_const {
-                            feature_err(
-                                sess,
-                                sym::asm_const,
-                                *op_sp,
-                                "const operands for inline assembly are unstable",
-                            )
-                            .emit();
-                        }
-                        hir::InlineAsmOperand::Const {
-                            anon_const: self.lower_anon_const_to_anon_const(anon_const),
-                        }
-                    }
+                    InlineAsmOperand::Const { anon_const } => hir::InlineAsmOperand::Const {
+                        anon_const: self.lower_anon_const_to_anon_const(anon_const),
+                    },
                     InlineAsmOperand::Sym { sym } => {
                         let static_def_id = self
                             .resolver
@@ -246,7 +242,7 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
                                 sess,
                                 sym::asm_goto,
                                 *op_sp,
-                                "label operands for inline assembly are unstable",
+                                fluent::ast_lowering_unstable_inline_assembly_label_operands,
                             )
                             .emit();
                         }

compiler/rustc_ast_lowering/src/delegation.rs

@@ -189,7 +189,7 @@ impl<'hir> LoweringContext<'_, 'hir> {
     ) -> hir::FnSig<'hir> {
         let header = if let Some(local_sig_id) = sig_id.as_local() {
             match self.resolver.delegation_fn_sigs.get(&local_sig_id) {
-                Some(sig) => self.lower_fn_header(sig.header),
+                Some(sig) => self.lower_fn_header(sig.header, hir::Safety::Safe),
                 None => self.generate_header_error(),
             }
         } else {
@@ -275,8 +275,8 @@ impl<'hir> LoweringContext<'_, 'hir> {
     // FIXME(fn_delegation): Alternatives for target expression lowering:
     // https://github.com/rust-lang/rfcs/pull/3530#issuecomment-2197170600.
     fn lower_target_expr(&mut self, block: &Block) -> hir::Expr<'hir> {
-        if block.stmts.len() == 1
-            && let StmtKind::Expr(expr) = &block.stmts[0].kind
+        if let [stmt] = block.stmts.as_slice()
+            && let StmtKind::Expr(expr) = &stmt.kind
         {
             return self.lower_expr_mut(expr);
         }

compiler/rustc_ast_lowering/src/expr.rs

@@ -23,7 +23,7 @@ use super::{
     ImplTraitContext, LoweringContext, ParamMode, ParenthesizedGenericArgs, ResolverAstLoweringExt,
 };
 use crate::errors::YieldInClosure;
-use crate::{FnDeclKind, ImplTraitPosition};
+use crate::{fluent_generated, FnDeclKind, ImplTraitPosition};
 
 impl<'hir> LoweringContext<'_, 'hir> {
     fn lower_exprs(&mut self, exprs: &[AstP<Expr>]) -> &'hir [hir::Expr<'hir>] {
@@ -1540,7 +1540,6 @@ impl<'hir> LoweringContext<'_, 'hir> {
         }
     }
 
-    #[allow(rustc::untranslatable_diagnostic)] // FIXME: make this translatable
     fn lower_expr_yield(&mut self, span: Span, opt_expr: Option<&Expr>) -> hir::ExprKind<'hir> {
         let yielded =
             opt_expr.as_ref().map(|x| self.lower_expr(x)).unwrap_or_else(|| self.expr_unit(span));
@@ -1575,7 +1574,7 @@ impl<'hir> LoweringContext<'_, 'hir> {
                         &self.tcx.sess,
                         sym::coroutines,
                         span,
-                        "yield syntax is experimental",
+                        fluent_generated::ast_lowering_yield,
                     )
                     .emit();
                 }
@@ -1587,7 +1586,7 @@ impl<'hir> LoweringContext<'_, 'hir> {
                         &self.tcx.sess,
                         sym::coroutines,
                         span,
-                        "yield syntax is experimental",
+                        fluent_generated::ast_lowering_yield,
                     )
                     .emit();
                 }

compiler/rustc_ast_lowering/src/item.rs

@@ -237,7 +237,7 @@ impl<'hir> LoweringContext<'_, 'hir> {
                         });
                     let sig = hir::FnSig {
                         decl,
-                        header: this.lower_fn_header(*header),
+                        header: this.lower_fn_header(*header, hir::Safety::Safe),
                         span: this.lower_span(*fn_sig_span),
                     };
                     hir::ItemKind::Fn(sig, generics, body_id)
@@ -668,7 +668,7 @@ impl<'hir> LoweringContext<'_, 'hir> {
                 ForeignItemKind::Fn(box Fn { sig, generics, .. }) => {
                     let fdec = &sig.decl;
                     let itctx = ImplTraitContext::Universal;
-                    let (generics, (fn_dec, fn_args)) =
+                    let (generics, (decl, fn_args)) =
                         self.lower_generics(generics, Const::No, false, i.id, itctx, |this| {
                             (
                                 // Disallow `impl Trait` in foreign items.
@@ -682,9 +682,15 @@ impl<'hir> LoweringContext<'_, 'hir> {
                                 this.lower_fn_params_to_names(fdec),
                             )
                         });
-                    let safety = self.lower_safety(sig.header.safety, hir::Safety::Unsafe);
 
-                    hir::ForeignItemKind::Fn(fn_dec, fn_args, generics, safety)
+                    // Unmarked safety in unsafe block defaults to unsafe.
+                    let header = self.lower_fn_header(sig.header, hir::Safety::Unsafe);
+
+                    hir::ForeignItemKind::Fn(
+                        hir::FnSig { header, decl, span: self.lower_span(sig.span) },
+                        fn_args,
+                        generics,
+                    )
                 }
                 ForeignItemKind::Static(box StaticItem { ty, mutability, expr: _, safety }) => {
                     let ty = self
@@ -1390,7 +1396,7 @@ impl<'hir> LoweringContext<'_, 'hir> {
         coroutine_kind: Option<CoroutineKind>,
         parent_constness: Const,
     ) -> (&'hir hir::Generics<'hir>, hir::FnSig<'hir>) {
-        let header = self.lower_fn_header(sig.header);
+        let header = self.lower_fn_header(sig.header, hir::Safety::Safe);
         // Don't pass along the user-provided constness of trait associated functions; we don't want to
         // synthesize a host effect param for them. We reject `const` on them during AST validation.
         let constness =
@@ -1403,14 +1409,18 @@ impl<'hir> LoweringContext<'_, 'hir> {
         (generics, hir::FnSig { header, decl, span: self.lower_span(sig.span) })
     }
 
-    pub(super) fn lower_fn_header(&mut self, h: FnHeader) -> hir::FnHeader {
+    pub(super) fn lower_fn_header(
+        &mut self,
+        h: FnHeader,
+        default_safety: hir::Safety,
+    ) -> hir::FnHeader {
         let asyncness = if let Some(CoroutineKind::Async { span, .. }) = h.coroutine_kind {
             hir::IsAsync::Async(span)
         } else {
             hir::IsAsync::NotAsync
         };
         hir::FnHeader {
-            safety: self.lower_safety(h.safety, hir::Safety::Safe),
+            safety: self.lower_safety(h.safety, default_safety),
             asyncness: asyncness,
             constness: self.lower_constness(h.constness),
             abi: self.lower_extern(h.ext),

compiler/rustc_ast_lowering/src/lib.rs

@@ -2326,7 +2326,6 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
         self.expr_block(block)
     }
 
-    #[allow(rustc::untranslatable_diagnostic)] // FIXME: make this translatable
     fn lower_array_length(&mut self, c: &AnonConst) -> hir::ArrayLen<'hir> {
         match c.value.kind {
             ExprKind::Underscore => {
@@ -2340,7 +2339,7 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
                         &self.tcx.sess,
                         sym::generic_arg_infer,
                         c.value.span,
-                        "using `_` for array lengths is unstable",
+                        fluent_generated::ast_lowering_underscore_array_length_unstable,
                     )
                     .stash(c.value.span, StashKey::UnderscoreForArrayLengths);
                     hir::ArrayLen::Body(self.lower_anon_const_to_const_arg(c))

compiler/rustc_ast_passes/src/ast_validation.rs

@@ -887,7 +887,7 @@ fn validate_generic_param_order(dcx: DiagCtxtHandle<'_>, generics: &[GenericPara
 
 impl<'a> Visitor<'a> for AstValidator<'a> {
     fn visit_attribute(&mut self, attr: &Attribute) {
-        validate_attr::check_attr(&self.features, &self.session.psess, attr);
+        validate_attr::check_attr(&self.session.psess, attr);
     }
 
     fn visit_ty(&mut self, ty: &'a Ty) {

compiler/rustc_ast_passes/src/feature_gate.rs

@@ -559,7 +559,6 @@ pub fn check_crate(krate: &ast::Crate, sess: &Session, features: &Features) {
     gate_all!(mut_ref, "mutable by-reference bindings are experimental");
     gate_all!(precise_capturing, "precise captures on `impl Trait` are experimental");
     gate_all!(global_registration, "global registration is experimental");
-    gate_all!(unsafe_attributes, "`#[unsafe()]` markers for attributes are experimental");
     gate_all!(return_type_notation, "return type notation is experimental");
 
     if !visitor.features.never_patterns {

compiler/rustc_ast_pretty/src/pprust/state.rs

@@ -502,8 +502,8 @@ pub trait PrintState<'a>: std::ops::Deref<Target = pp::Printer> + std::ops::Dere
                 if !self.is_beginning_of_line() {
                     self.word(" ");
                 }
-                if cmnt.lines.len() == 1 {
-                    self.word(cmnt.lines[0].clone());
+                if let [line] = cmnt.lines.as_slice() {
+                    self.word(line.clone());
                     self.hardbreak()
                 } else {
                     self.visual_align();

compiler/rustc_ast_pretty/src/pprust/state/item.rs

@@ -783,8 +783,8 @@ impl<'a> State<'a> {
                 }
                 if items.is_empty() {
                     self.word("{}");
-                } else if items.len() == 1 {
-                    self.print_use_tree(&items[0].0);
+                } else if let [(item, _)] = items.as_slice() {
+                    self.print_use_tree(item);
                 } else {
                     self.cbox(INDENT_UNIT);
                     self.word("{");

compiler/rustc_attr/messages.ftl

@@ -104,6 +104,9 @@ attr_unknown_meta_item =
 attr_unknown_version_literal =
     unknown version literal format, assuming it refers to a future version
 
+attr_unstable_cfg_target_compact =
+    compact `cfg(target(..))` is experimental and subject to change
+
 attr_unsupported_literal_cfg_string =
     literal in `cfg` predicate value must be a string
 attr_unsupported_literal_deprecated_kv_pair =