diff options
Diffstat (limited to 'compiler/rustc_ast_passes/src/feature_gate.rs')
| -rw-r--r-- | compiler/rustc_ast_passes/src/feature_gate.rs | 92 |
1 files changed, 50 insertions, 42 deletions
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); |