diff options
| -rw-r--r-- | compiler/rustc_ast/src/ast.rs | 9 | ||||
| -rw-r--r-- | compiler/rustc_ast_lowering/src/expr.rs | 9 | ||||
| -rw-r--r-- | compiler/rustc_ast_lowering/src/item.rs | 120 |
3 files changed, 121 insertions, 17 deletions
diff --git a/compiler/rustc_ast/src/ast.rs b/compiler/rustc_ast/src/ast.rs index a398fd80119..a7198fbf887 100644 --- a/compiler/rustc_ast/src/ast.rs +++ b/compiler/rustc_ast/src/ast.rs @@ -2652,6 +2652,15 @@ pub struct NormalAttr { pub tokens: Option<LazyAttrTokenStream>, } +impl NormalAttr { + pub fn from_ident(ident: Ident) -> Self { + Self { + item: AttrItem { path: Path::from_ident(ident), args: AttrArgs::Empty, tokens: None }, + tokens: None, + } + } +} + #[derive(Clone, Encodable, Decodable, Debug, HashStable_Generic)] pub struct AttrItem { pub path: Path, diff --git a/compiler/rustc_ast_lowering/src/expr.rs b/compiler/rustc_ast_lowering/src/expr.rs index 29972dd76eb..dcaaaafedbe 100644 --- a/compiler/rustc_ast_lowering/src/expr.rs +++ b/compiler/rustc_ast_lowering/src/expr.rs @@ -673,14 +673,7 @@ impl<'hir> LoweringContext<'_, 'hir> { self.lower_attrs( inner_hir_id, &[Attribute { - kind: AttrKind::Normal(ptr::P(NormalAttr { - item: AttrItem { - path: Path::from_ident(Ident::new(sym::track_caller, span)), - args: AttrArgs::Empty, - tokens: None, - }, - tokens: None, - })), + kind: AttrKind::Normal(ptr::P(NormalAttr::from_ident(Ident::new(sym::track_caller, span)))), id: self.tcx.sess.parse_sess.attr_id_generator.mk_attr_id(), style: AttrStyle::Outer, span: unstable_span, diff --git a/compiler/rustc_ast_lowering/src/item.rs b/compiler/rustc_ast_lowering/src/item.rs index 08ee3761bac..5681d365aa1 100644 --- a/compiler/rustc_ast_lowering/src/item.rs +++ b/compiler/rustc_ast_lowering/src/item.rs @@ -3,6 +3,7 @@ use super::ResolverAstLoweringExt; use super::{AstOwner, ImplTraitContext, ImplTraitPosition}; use super::{FnDeclKind, LoweringContext, ParamMode}; +use hir::definitions::DefPathData; use rustc_ast::ptr::P; use rustc_ast::visit::AssocCtxt; use rustc_ast::*; @@ -257,10 +258,11 @@ impl<'hir> LoweringContext<'_, 'hir> { ); let itctx = ImplTraitContext::Universal; - let (generics, decl) = this.lower_generics(generics, id, &itctx, |this| { - let ret_id = asyncness.opt_return_id(); - this.lower_fn_decl(&decl, id, *fn_sig_span, FnDeclKind::Fn, ret_id) - }); + let (generics, decl) = + this.lower_generics(generics, header.constness, id, &itctx, |this| { + let ret_id = asyncness.opt_return_id(); + this.lower_fn_decl(&decl, id, *fn_sig_span, FnDeclKind::Fn, ret_id) + }); let sig = hir::FnSig { decl, header: this.lower_fn_header(*header), @@ -295,6 +297,7 @@ impl<'hir> LoweringContext<'_, 'hir> { add_ty_alias_where_clause(&mut generics, *where_clauses, true); let (generics, ty) = self.lower_generics( &generics, + Const::No, id, &ImplTraitContext::Disallowed(ImplTraitPosition::Generic), |this| match ty { @@ -316,6 +319,7 @@ impl<'hir> LoweringContext<'_, 'hir> { ItemKind::Enum(enum_definition, generics) => { let (generics, variants) = self.lower_generics( generics, + Const::No, id, &ImplTraitContext::Disallowed(ImplTraitPosition::Generic), |this| { @@ -329,6 +333,7 @@ impl<'hir> LoweringContext<'_, 'hir> { ItemKind::Struct(struct_def, generics) => { let (generics, struct_def) = self.lower_generics( generics, + Const::No, id, &ImplTraitContext::Disallowed(ImplTraitPosition::Generic), |this| this.lower_variant_data(hir_id, struct_def), @@ -338,6 +343,7 @@ impl<'hir> LoweringContext<'_, 'hir> { ItemKind::Union(vdata, generics) => { let (generics, vdata) = self.lower_generics( generics, + Const::No, id, &ImplTraitContext::Disallowed(ImplTraitPosition::Generic), |this| this.lower_variant_data(hir_id, vdata), @@ -369,7 +375,7 @@ impl<'hir> LoweringContext<'_, 'hir> { // parent lifetime. let itctx = ImplTraitContext::Universal; let (generics, (trait_ref, lowered_ty)) = - self.lower_generics(ast_generics, id, &itctx, |this| { + self.lower_generics(ast_generics, *constness, id, &itctx, |this| { let trait_ref = trait_ref.as_ref().map(|trait_ref| { this.lower_trait_ref( trait_ref, @@ -410,8 +416,18 @@ impl<'hir> LoweringContext<'_, 'hir> { })) } ItemKind::Trait(box Trait { is_auto, unsafety, generics, bounds, items }) => { + // FIXME(const_trait_impl, effects, fee1-dead) this should be simplified if possible + let constness = if let Some(attrs) = attrs { + attrs + .iter() + .find(|x| x.has_name(sym::const_trait)) + .map_or(Const::No, |x| Const::Yes(x.span)) + } else { + Const::No + }; let (generics, (unsafety, items, bounds)) = self.lower_generics( generics, + constness, id, &ImplTraitContext::Disallowed(ImplTraitPosition::Generic), |this| { @@ -431,6 +447,7 @@ impl<'hir> LoweringContext<'_, 'hir> { ItemKind::TraitAlias(generics, bounds) => { let (generics, bounds) = self.lower_generics( generics, + Const::No, id, &ImplTraitContext::Disallowed(ImplTraitPosition::Generic), |this| { @@ -593,7 +610,7 @@ impl<'hir> LoweringContext<'_, 'hir> { let fdec = &sig.decl; let itctx = ImplTraitContext::Universal; let (generics, (fn_dec, fn_args)) = - self.lower_generics(generics, i.id, &itctx, |this| { + self.lower_generics(generics, Const::No, i.id, &itctx, |this| { ( // Disallow `impl Trait` in foreign items. this.lower_fn_decl( @@ -745,6 +762,7 @@ impl<'hir> LoweringContext<'_, 'hir> { add_ty_alias_where_clause(&mut generics, *where_clauses, false); let (generics, kind) = self.lower_generics( &generics, + Const::No, i.id, &ImplTraitContext::Disallowed(ImplTraitPosition::Generic), |this| { @@ -843,6 +861,7 @@ impl<'hir> LoweringContext<'_, 'hir> { add_ty_alias_where_clause(&mut generics, *where_clauses, false); self.lower_generics( &generics, + Const::No, i.id, &ImplTraitContext::Disallowed(ImplTraitPosition::Generic), |this| match ty { @@ -1201,9 +1220,10 @@ impl<'hir> LoweringContext<'_, 'hir> { ) -> (&'hir hir::Generics<'hir>, hir::FnSig<'hir>) { let header = self.lower_fn_header(sig.header); let itctx = ImplTraitContext::Universal; - let (generics, decl) = self.lower_generics(generics, id, &itctx, |this| { - this.lower_fn_decl(&sig.decl, id, sig.span, kind, is_async) - }); + let (generics, decl) = + self.lower_generics(generics, sig.header.constness, id, &itctx, |this| { + this.lower_fn_decl(&sig.decl, id, sig.span, kind, is_async) + }); (generics, hir::FnSig { header, decl, span: self.lower_span(sig.span) }) } @@ -1275,6 +1295,7 @@ impl<'hir> LoweringContext<'_, 'hir> { fn lower_generics<T>( &mut self, generics: &Generics, + constness: Const, parent_node_id: NodeId, itctx: &ImplTraitContext, f: impl FnOnce(&mut Self) -> T, @@ -1372,6 +1393,87 @@ impl<'hir> LoweringContext<'_, 'hir> { let impl_trait_bounds = std::mem::take(&mut self.impl_trait_bounds); predicates.extend(impl_trait_bounds.into_iter()); + // Desugar `~const` bound in generics into an additional `const host: bool` param + // if the effects feature is enabled. + if let Const::Yes(span) = constness && self.tcx.features().effects + // Do not add host param if it already has it (manually specified) + && !params.iter().any(|x| { + self.attrs.get(&x.hir_id.local_id).map_or(false, |attrs| { + attrs.iter().any(|x| x.has_name(sym::rustc_host)) + }) + }) + { + let param_node_id = self.next_node_id(); + let const_node_id = self.next_node_id(); + let def_id = self.create_def(self.local_def_id(parent_node_id), param_node_id, DefPathData::TypeNs(sym::host), span); + let anon_const: LocalDefId = self.create_def(def_id, const_node_id, DefPathData::AnonConst, span); + + let hir_id = self.next_id(); + let const_id = self.next_id(); + let const_expr_id = self.next_id(); + let bool_id = self.next_id(); + + self.children.push((def_id, hir::MaybeOwner::NonOwner(hir_id))); + self.children.push((anon_const, hir::MaybeOwner::NonOwner(const_id))); + + let attr_id = self.tcx.sess.parse_sess.attr_id_generator.mk_attr_id(); + + let attrs = self.arena.alloc_from_iter([ + Attribute { + kind: AttrKind::Normal(P(NormalAttr::from_ident(Ident::new(sym::rustc_host, span)))), + span, + id: attr_id, + style: AttrStyle::Outer, + }, + ]); + self.attrs.insert(hir_id.local_id, attrs); + + let const_body = self.lower_body(|this| { + ( + &[], + hir::Expr { + hir_id: const_expr_id, + kind: hir::ExprKind::Lit( + this.arena.alloc(hir::Lit { node: LitKind::Bool(true), span }), + ), + span, + }, + ) + }); + + let param = hir::GenericParam { + def_id, + hir_id, + name: hir::ParamName::Plain(Ident { name: sym::host, span }), + span, + kind: hir::GenericParamKind::Const { + ty: self.arena.alloc(self.ty( + span, + hir::TyKind::Path(hir::QPath::Resolved( + None, + self.arena.alloc(hir::Path { + res: Res::PrimTy(hir::PrimTy::Bool), + span, + segments: self.arena.alloc_from_iter([hir::PathSegment { + ident: Ident { name: sym::bool, span }, + hir_id: bool_id, + res: Res::PrimTy(hir::PrimTy::Bool), + args: None, + infer_args: false, + }]), + }), + )), + )), + default: Some(hir::AnonConst { def_id: anon_const, hir_id: const_id, body: const_body }), + }, + colon_span: None, + pure_wrt_drop: false, + source: hir::GenericParamSource::Generics, + }; + + params.push(param); + } + let lowered_generics = self.arena.alloc(hir::Generics { params: self.arena.alloc_from_iter(params), predicates: self.arena.alloc_from_iter(predicates), |