Merging upstream version 1.70.0+dfsg1.

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

4 files changed, 101 insertions, 87 deletions

diff --git a/compiler/rustc_ast_passes/src/ast_validation.rs b/compiler/rustc_ast_passes/src/ast_validation.rs
index 2cc009410..c79626ccd 100644
--- a/compiler/rustc_ast_passes/src/ast_validation.rs
+++ b/compiler/rustc_ast_passes/src/ast_validation.rs
@@ -9,10 +9,10 @@
 use itertools::{Either, Itertools};
 use rustc_ast::ptr::P;
 use rustc_ast::visit::{self, AssocCtxt, BoundKind, FnCtxt, FnKind, Visitor};
-use rustc_ast::walk_list;
 use rustc_ast::*;
+use rustc_ast::{walk_list, StaticItem};
 use rustc_ast_pretty::pprust::{self, State};
-use rustc_data_structures::fx::FxHashMap;
+use rustc_data_structures::fx::FxIndexMap;
 use rustc_macros::Subdiagnostic;
 use rustc_parse::validate_attr;
 use rustc_session::lint::builtin::{
@@ -240,16 +240,12 @@ impl<'a> AstValidator<'a> {
         }
     }
 
-    fn invalid_visibility(&self, vis: &Visibility, note: Option<errors::InvalidVisibilityNote>) {
+    fn visibility_not_permitted(&self, vis: &Visibility, note: errors::VisibilityNotPermittedNote) {
         if let VisibilityKind::Inherited = vis.kind {
             return;
         }
 
-        self.session.emit_err(errors::InvalidVisibility {
-            span: vis.span,
-            implied: vis.kind.is_pub().then_some(vis.span),
-            note,
-        });
+        self.session.emit_err(errors::VisibilityNotPermitted { span: vis.span, note });
     }
 
     fn check_decl_no_pat(decl: &FnDecl, mut report_err: impl FnMut(Span, Option<Ident>, bool)) {
@@ -643,7 +639,7 @@ fn validate_generic_param_order(
     span: Span,
 ) {
     let mut max_param: Option<ParamKindOrd> = None;
-    let mut out_of_order = FxHashMap::default();
+    let mut out_of_order = FxIndexMap::default();
     let mut param_idents = Vec::with_capacity(generics.len());
 
     for (idx, param) in generics.iter().enumerate() {
@@ -691,7 +687,7 @@ fn validate_generic_param_order(
                 GenericParamKind::Lifetime => (),
                 GenericParamKind::Const { ty: _, kw_span: _, default: Some(default) } => {
                     ordered_params += " = ";
-                    ordered_params += &pprust::expr_to_string(&*default.value);
+                    ordered_params += &pprust::expr_to_string(&default.value);
                 }
                 GenericParamKind::Const { ty: _, kw_span: _, default: None } => (),
             }
@@ -799,11 +795,11 @@ impl<'a> Visitor<'a> for AstValidator<'a> {
     }
 
     fn visit_item(&mut self, item: &'a Item) {
-        if item.attrs.iter().any(|attr| self.session.is_proc_macro_attr(attr)) {
+        if item.attrs.iter().any(|attr| attr.is_proc_macro_attr()) {
             self.has_proc_macro_decls = true;
         }
 
-        if self.session.contains_name(&item.attrs, sym::no_mangle) {
+        if attr::contains_name(&item.attrs, sym::no_mangle) {
             self.check_nomangle_item_asciionly(item.ident, item.span);
         }
 
@@ -819,7 +815,10 @@ impl<'a> Visitor<'a> for AstValidator<'a> {
                 items,
             }) => {
                 self.with_in_trait_impl(true, Some(*constness), |this| {
-                    this.invalid_visibility(&item.vis, None);
+                    this.visibility_not_permitted(
+                        &item.vis,
+                        errors::VisibilityNotPermittedNote::TraitImpl,
+                    );
                     if let TyKind::Err = self_ty.kind {
                         this.err_handler().emit_err(errors::ObsoleteAuto { span: item.span });
                     }
@@ -866,9 +865,9 @@ impl<'a> Visitor<'a> for AstValidator<'a> {
                         only_trait: only_trait.then_some(()),
                     };
 
-                self.invalid_visibility(
+                self.visibility_not_permitted(
                     &item.vis,
-                    Some(errors::InvalidVisibilityNote::IndividualImplItems),
+                    errors::VisibilityNotPermittedNote::IndividualImplItems,
                 );
                 if let &Unsafe::Yes(span) = unsafety {
                     self.err_handler().emit_err(errors::InherentImplCannotUnsafe {
@@ -924,9 +923,9 @@ impl<'a> Visitor<'a> for AstValidator<'a> {
             }
             ItemKind::ForeignMod(ForeignMod { abi, unsafety, .. }) => {
                 let old_item = mem::replace(&mut self.extern_mod, Some(item));
-                self.invalid_visibility(
+                self.visibility_not_permitted(
                     &item.vis,
-                    Some(errors::InvalidVisibilityNote::IndividualForeignItems),
+                    errors::VisibilityNotPermittedNote::IndividualForeignItems,
                 );
                 if let &Unsafe::Yes(span) = unsafety {
                     self.err_handler().emit_err(errors::UnsafeItem { span, kind: "extern block" });
@@ -940,9 +939,15 @@ impl<'a> Visitor<'a> for AstValidator<'a> {
             }
             ItemKind::Enum(def, _) => {
                 for variant in &def.variants {
-                    self.invalid_visibility(&variant.vis, None);
+                    self.visibility_not_permitted(
+                        &variant.vis,
+                        errors::VisibilityNotPermittedNote::EnumVariant,
+                    );
                     for field in variant.data.fields() {
-                        self.invalid_visibility(&field.vis, None);
+                        self.visibility_not_permitted(
+                            &field.vis,
+                            errors::VisibilityNotPermittedNote::EnumVariant,
+                        );
                     }
                 }
             }
@@ -973,7 +978,7 @@ impl<'a> Visitor<'a> for AstValidator<'a> {
                 }
                 // Ensure that `path` attributes on modules are recorded as used (cf. issue #35584).
                 if !matches!(mod_kind, ModKind::Loaded(_, Inline::Yes, _))
-                    && !self.session.contains_name(&item.attrs, sym::path)
+                    && !attr::contains_name(&item.attrs, sym::path)
                 {
                     self.check_mod_file_item_asciionly(item.ident);
                 }
@@ -983,14 +988,14 @@ impl<'a> Visitor<'a> for AstValidator<'a> {
                     self.err_handler().emit_err(errors::FieldlessUnion { span: item.span });
                 }
             }
-            ItemKind::Const(def, .., None) => {
-                self.check_defaultness(item.span, *def);
+            ItemKind::Const(box ConstItem { defaultness, expr: None, .. }) => {
+                self.check_defaultness(item.span, *defaultness);
                 self.session.emit_err(errors::ConstWithoutBody {
                     span: item.span,
                     replace_span: self.ending_semi_or_hi(item.span),
                 });
             }
-            ItemKind::Static(.., None) => {
+            ItemKind::Static(box StaticItem { expr: None, .. }) => {
                 self.session.emit_err(errors::StaticWithoutBody {
                     span: item.span,
                     replace_span: self.ending_semi_or_hi(item.span),
@@ -1248,7 +1253,7 @@ impl<'a> Visitor<'a> for AstValidator<'a> {
     }
 
     fn visit_assoc_item(&mut self, item: &'a AssocItem, ctxt: AssocCtxt) {
-        if self.session.contains_name(&item.attrs, sym::no_mangle) {
+        if attr::contains_name(&item.attrs, sym::no_mangle) {
             self.check_nomangle_item_asciionly(item.ident, item.span);
         }
 
@@ -1258,13 +1263,11 @@ impl<'a> Visitor<'a> for AstValidator<'a> {
 
         if ctxt == AssocCtxt::Impl {
             match &item.kind {
-                AssocItemKind::Const(_, _, body) => {
-                    if body.is_none() {
-                        self.session.emit_err(errors::AssocConstWithoutBody {
-                            span: item.span,
-                            replace_span: self.ending_semi_or_hi(item.span),
-                        });
-                    }
+                AssocItemKind::Const(box ConstItem { expr: None, .. }) => {
+                    self.session.emit_err(errors::AssocConstWithoutBody {
+                        span: item.span,
+                        replace_span: self.ending_semi_or_hi(item.span),
+                    });
                 }
                 AssocItemKind::Fn(box Fn { body, .. }) => {
                     if body.is_none() {
@@ -1302,7 +1305,7 @@ impl<'a> Visitor<'a> for AstValidator<'a> {
         }
 
         if ctxt == AssocCtxt::Trait || self.in_trait_impl {
-            self.invalid_visibility(&item.vis, None);
+            self.visibility_not_permitted(&item.vis, errors::VisibilityNotPermittedNote::TraitImpl);
             if let AssocItemKind::Fn(box Fn { sig, .. }) = &item.kind {
                 self.check_trait_fn_not_const(sig.header.constness);
             }
@@ -1392,11 +1395,13 @@ fn deny_equality_constraints(
                                             }
                                         },
                                         empty_args => {
-                                            *empty_args = AngleBracketedArgs {
-                                                span: ident.span,
-                                                args: thin_vec![arg],
-                                            }
-                                            .into();
+                                            *empty_args = Some(
+                                                AngleBracketedArgs {
+                                                    span: ident.span,
+                                                    args: thin_vec![arg],
+                                                }
+                                                .into(),
+                                            );
                                         }
                                     }
                                     err.assoc = Some(errors::AssociatedSuggestion {
diff --git a/compiler/rustc_ast_passes/src/errors.rs b/compiler/rustc_ast_passes/src/errors.rs
index d007097d9..27bbd2379 100644
--- a/compiler/rustc_ast_passes/src/errors.rs
+++ b/compiler/rustc_ast_passes/src/errors.rs
@@ -42,18 +42,20 @@ pub struct InvalidLabel {
 }
 
 #[derive(Diagnostic)]
-#[diag(ast_passes_invalid_visibility, code = "E0449")]
-pub struct InvalidVisibility {
+#[diag(ast_passes_visibility_not_permitted, code = "E0449")]
+pub struct VisibilityNotPermitted {
     #[primary_span]
     pub span: Span,
-    #[label(ast_passes_implied)]
-    pub implied: Option<Span>,
     #[subdiagnostic]
-    pub note: Option<InvalidVisibilityNote>,
+    pub note: VisibilityNotPermittedNote,
 }
 
 #[derive(Subdiagnostic)]
-pub enum InvalidVisibilityNote {
+pub enum VisibilityNotPermittedNote {
+    #[note(ast_passes_enum_variant)]
+    EnumVariant,
+    #[note(ast_passes_trait_impl)]
+    TraitImpl,
     #[note(ast_passes_individual_impl_items)]
     IndividualImplItems,
     #[note(ast_passes_individual_foreign_items)]
diff --git a/compiler/rustc_ast_passes/src/feature_gate.rs b/compiler/rustc_ast_passes/src/feature_gate.rs
index 96042ea30..17bcd24ee 100644
--- a/compiler/rustc_ast_passes/src/feature_gate.rs
+++ b/compiler/rustc_ast_passes/src/feature_gate.rs
@@ -1,6 +1,6 @@
 use rustc_ast as ast;
 use rustc_ast::visit::{self, AssocCtxt, FnCtxt, FnKind, Visitor};
-use rustc_ast::{AssocConstraint, AssocConstraintKind, NodeId};
+use rustc_ast::{attr, AssocConstraint, AssocConstraintKind, NodeId};
 use rustc_ast::{PatKind, RangeEnd};
 use rustc_errors::{Applicability, StashKey};
 use rustc_feature::{AttributeGate, BuiltinAttribute, Features, GateIssue, BUILTIN_ATTRIBUTE_MAP};
@@ -121,24 +121,34 @@ impl<'a> PostExpansionVisitor<'a> {
     }
 
     /// Feature gate `impl Trait` inside `type Alias = $type_expr;`.
-    fn check_impl_trait(&self, ty: &ast::Ty) {
+    fn check_impl_trait(&self, ty: &ast::Ty, in_associated_ty: bool) {
         struct ImplTraitVisitor<'a> {
             vis: &'a PostExpansionVisitor<'a>,
+            in_associated_ty: bool,
         }
         impl Visitor<'_> for ImplTraitVisitor<'_> {
             fn visit_ty(&mut self, ty: &ast::Ty) {
                 if let ast::TyKind::ImplTrait(..) = ty.kind {
-                    gate_feature_post!(
-                        &self.vis,
-                        type_alias_impl_trait,
-                        ty.span,
-                        "`impl Trait` in type aliases is unstable"
-                    );
+                    if self.in_associated_ty {
+                        gate_feature_post!(
+                            &self.vis,
+                            impl_trait_in_assoc_type,
+                            ty.span,
+                            "`impl Trait` in associated types is unstable"
+                        );
+                    } else {
+                        gate_feature_post!(
+                            &self.vis,
+                            type_alias_impl_trait,
+                            ty.span,
+                            "`impl Trait` in type aliases is unstable"
+                        );
+                    }
                 }
                 visit::walk_ty(self, ty);
             }
         }
-        ImplTraitVisitor { vis: self }.visit_ty(ty);
+        ImplTraitVisitor { vis: self, in_associated_ty }.visit_ty(ty);
     }
 
     fn check_late_bound_lifetime_defs(&self, params: &[ast::GenericParam]) {
@@ -232,7 +242,7 @@ impl<'a> Visitor<'a> for PostExpansionVisitor<'a> {
             }
 
             ast::ItemKind::Fn(..) => {
-                if self.sess.contains_name(&i.attrs, sym::start) {
+                if attr::contains_name(&i.attrs, sym::start) {
                     gate_feature_post!(
                         &self,
                         start,
@@ -245,7 +255,7 @@ impl<'a> Visitor<'a> for PostExpansionVisitor<'a> {
             }
 
             ast::ItemKind::Struct(..) => {
-                for attr in self.sess.filter_by_name(&i.attrs, sym::repr) {
+                for attr in attr::filter_by_name(&i.attrs, sym::repr) {
                     for item in attr.meta_item_list().unwrap_or_else(ThinVec::new) {
                         if item.has_name(sym::simd) {
                             gate_feature_post!(
@@ -294,7 +304,7 @@ impl<'a> Visitor<'a> for PostExpansionVisitor<'a> {
             }
 
             ast::ItemKind::TyAlias(box ast::TyAlias { ty: Some(ty), .. }) => {
-                self.check_impl_trait(&ty)
+                self.check_impl_trait(&ty, false)
             }
 
             _ => {}
@@ -306,7 +316,7 @@ impl<'a> Visitor<'a> for PostExpansionVisitor<'a> {
     fn visit_foreign_item(&mut self, i: &'a ast::ForeignItem) {
         match i.kind {
             ast::ForeignItemKind::Fn(..) | ast::ForeignItemKind::Static(..) => {
-                let link_name = self.sess.first_attr_value_str_by_name(&i.attrs, sym::link_name);
+                let link_name = attr::first_attr_value_str_by_name(&i.attrs, sym::link_name);
                 let links_to_llvm =
                     link_name.map_or(false, |val| val.as_str().starts_with("llvm."));
                 if links_to_llvm {
@@ -337,9 +347,6 @@ impl<'a> Visitor<'a> for PostExpansionVisitor<'a> {
             ast::TyKind::Never => {
                 gate_feature_post!(&self, never_type, ty.span, "the `!` type is experimental");
             }
-            ast::TyKind::TraitObject(_, ast::TraitObjectSyntax::DynStar, ..) => {
-                gate_feature_post!(&self, dyn_star, ty.span, "dyn* trait objects are unstable");
-            }
             _ => {}
         }
         visit::walk_ty(self, ty)
@@ -395,14 +402,6 @@ impl<'a> Visitor<'a> for PostExpansionVisitor<'a> {
 
     fn visit_expr(&mut self, e: &'a ast::Expr) {
         match e.kind {
-            ast::ExprKind::Box(_) => {
-                gate_feature_post!(
-                    &self,
-                    box_syntax,
-                    e.span,
-                    "box expression syntax is experimental; you can call `Box::new` instead"
-                );
-            }
             ast::ExprKind::Type(..) => {
                 if self.sess.parse_sess.span_diagnostic.err_count() == 0 {
                     // To avoid noise about type ascription in common syntax errors,
@@ -415,24 +414,19 @@ impl<'a> Visitor<'a> for PostExpansionVisitor<'a> {
                     );
                 } else {
                     // And if it isn't, cancel the early-pass warning.
-                    self.sess
+                    if let Some(err) = self
+                        .sess
                         .parse_sess
                         .span_diagnostic
                         .steal_diagnostic(e.span, StashKey::EarlySyntaxWarning)
-                        .map(|err| err.cancel());
+                    {
+                        err.cancel()
+                    }
                 }
             }
             ast::ExprKind::TryBlock(_) => {
                 gate_feature_post!(&self, try_blocks, e.span, "`try` expression is experimental");
             }
-            ast::ExprKind::Closure(box ast::Closure { constness: ast::Const::Yes(_), .. }) => {
-                gate_feature_post!(
-                    &self,
-                    const_closures,
-                    e.span,
-                    "const closures are experimental"
-                );
-            }
             _ => {}
         }
         visit::walk_expr(self, e)
@@ -501,12 +495,24 @@ impl<'a> Visitor<'a> for PostExpansionVisitor<'a> {
 
     fn visit_assoc_constraint(&mut self, constraint: &'a AssocConstraint) {
         if let AssocConstraintKind::Bound { .. } = constraint.kind {
-            gate_feature_post!(
-                &self,
-                associated_type_bounds,
-                constraint.span,
-                "associated type bounds are unstable"
-            )
+            if let Some(ast::GenericArgs::Parenthesized(args)) = constraint.gen_args.as_ref()
+                && args.inputs.is_empty()
+                && matches!(args.output, ast::FnRetTy::Default(..))
+            {
+                gate_feature_post!(
+                    &self,
+                    return_type_notation,
+                    constraint.span,
+                    "return type notation is experimental"
+                );
+            } else {
+                gate_feature_post!(
+                    &self,
+                    associated_type_bounds,
+                    constraint.span,
+                    "associated type bounds are unstable"
+                );
+            }
         }
         visit::walk_assoc_constraint(self, constraint)
     }
@@ -524,7 +530,7 @@ impl<'a> Visitor<'a> for PostExpansionVisitor<'a> {
                     );
                 }
                 if let Some(ty) = ty {
-                    self.check_impl_trait(ty);
+                    self.check_impl_trait(ty, true);
                 }
                 false
             }
@@ -594,6 +600,8 @@ pub fn check_crate(krate: &ast::Crate, sess: &Session) {
     gate_all!(inline_const_pat, "inline-const in pattern position is experimental");
     gate_all!(associated_const_equality, "associated const equality is incomplete");
     gate_all!(yeet_expr, "`do yeet` expression is experimental");
+    gate_all!(dyn_star, "`dyn*` trait objects are experimental");
+    gate_all!(const_closures, "const closures are experimental");
 
     // All uses of `gate_all!` below this point were added in #65742,
     // and subsequently disabled (with the non-early gating readded).
@@ -609,11 +617,11 @@ pub fn check_crate(krate: &ast::Crate, sess: &Session) {
 
     gate_all!(trait_alias, "trait aliases are experimental");
     gate_all!(associated_type_bounds, "associated type bounds are unstable");
+    gate_all!(return_type_notation, "return type notation is experimental");
     gate_all!(decl_macro, "`macro` is experimental");
     gate_all!(box_patterns, "box pattern syntax is experimental");
     gate_all!(exclusive_range_pattern, "exclusive range pattern syntax is experimental");
     gate_all!(try_blocks, "`try` blocks are unstable");
-    gate_all!(box_syntax, "box expression syntax is experimental; you can call `Box::new` instead");
     gate_all!(type_ascription, "type ascription is experimental");
 
     visit::walk_crate(&mut visitor, krate);
diff --git a/compiler/rustc_ast_passes/src/lib.rs b/compiler/rustc_ast_passes/src/lib.rs
index b9dcaee23..e2c666604 100644
--- a/compiler/rustc_ast_passes/src/lib.rs
+++ b/compiler/rustc_ast_passes/src/lib.rs
@@ -4,7 +4,6 @@
 //!
 //! The crate also contains other misc AST visitors, e.g. `node_count` and `show_span`.
 
-#![allow(rustc::potential_query_instability)]
 #![feature(box_patterns)]
 #![feature(if_let_guard)]
 #![feature(iter_is_partitioned)]
@@ -22,4 +21,4 @@ pub mod feature_gate;
 pub mod node_count;
 pub mod show_span;
 
-fluent_messages! { "../locales/en-US.ftl" }
+fluent_messages! { "../messages.ftl" }