diff options
Diffstat (limited to 'compiler/rustc_ast_lowering/src/lib.rs')
| -rw-r--r-- | compiler/rustc_ast_lowering/src/lib.rs | 166 |
1 files changed, 79 insertions, 87 deletions
diff --git a/compiler/rustc_ast_lowering/src/lib.rs b/compiler/rustc_ast_lowering/src/lib.rs index b26797f4203..00eafeb4d84 100644 --- a/compiler/rustc_ast_lowering/src/lib.rs +++ b/compiler/rustc_ast_lowering/src/lib.rs @@ -55,8 +55,8 @@ use rustc_errors::{DiagArgFromDisplay, DiagCtxtHandle, StashKey}; use rustc_hir::def::{DefKind, LifetimeRes, Namespace, PartialRes, PerNS, Res}; use rustc_hir::def_id::{CRATE_DEF_ID, LOCAL_CRATE, LocalDefId, LocalDefIdMap}; use rustc_hir::{ - self as hir, ConstArg, GenericArg, HirId, ItemLocalMap, MissingLifetimeKind, ParamName, - TraitCandidate, + self as hir, ConstArg, GenericArg, HirId, ItemLocalMap, LangItem, MissingLifetimeKind, + ParamName, TraitCandidate, }; use rustc_index::{Idx, IndexSlice, IndexVec}; use rustc_macros::extension; @@ -765,8 +765,13 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> { res } - fn make_lang_item_qpath(&mut self, lang_item: hir::LangItem, span: Span) -> hir::QPath<'hir> { - hir::QPath::Resolved(None, self.make_lang_item_path(lang_item, span, None)) + fn make_lang_item_qpath( + &mut self, + lang_item: hir::LangItem, + span: Span, + args: Option<&'hir hir::GenericArgs<'hir>>, + ) -> hir::QPath<'hir> { + hir::QPath::Resolved(None, self.make_lang_item_path(lang_item, span, args)) } fn make_lang_item_path( @@ -1219,13 +1224,12 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> { let bound = this.lower_poly_trait_ref( &PolyTraitRef { bound_generic_params: ThinVec::new(), + modifiers: TraitBoundModifiers::NONE, trait_ref: TraitRef { path: path.clone(), ref_id: t.id }, span: t.span, }, itctx, - TraitBoundModifiers::NONE, ); - let bound = (bound, hir::TraitBoundModifier::None); let bounds = this.arena.alloc_from_iter([bound]); let lifetime_bound = this.elided_dyn_bound(t.span); (bounds, lifetime_bound) @@ -1259,46 +1263,6 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> { let kind = match &t.kind { TyKind::Infer => hir::TyKind::Infer, TyKind::Err(guar) => hir::TyKind::Err(*guar), - // Lower the anonymous structs or unions in a nested lowering context. - // - // ``` - // struct Foo { - // _: union { - // // ^__________________ <-- within the nested lowering context, - // /* fields */ // | we lower all fields defined into an - // } // | owner node of struct or union item - // // ^_____________________| - // } - // ``` - TyKind::AnonStruct(node_id, fields) | TyKind::AnonUnion(node_id, fields) => { - // Here its `def_id` is created in `build_reduced_graph`. - let def_id = self.local_def_id(*node_id); - debug!(?def_id); - let owner_id = hir::OwnerId { def_id }; - self.with_hir_id_owner(*node_id, |this| { - let fields = this.arena.alloc_from_iter( - fields.iter().enumerate().map(|f| this.lower_field_def(f)), - ); - let span = t.span; - let variant_data = - hir::VariantData::Struct { fields, recovered: ast::Recovered::No }; - // FIXME: capture the generics from the outer adt. - let generics = hir::Generics::empty(); - let kind = match t.kind { - TyKind::AnonStruct(..) => hir::ItemKind::Struct(variant_data, generics), - TyKind::AnonUnion(..) => hir::ItemKind::Union(variant_data, generics), - _ => unreachable!(), - }; - hir::OwnerNode::Item(this.arena.alloc(hir::Item { - ident: Ident::new(kw::Empty, span), - owner_id, - kind, - span: this.lower_span(span), - vis_span: this.lower_span(span.shrink_to_lo()), - })) - }); - hir::TyKind::AnonAdt(hir::ItemId { owner_id }) - } TyKind::Slice(ty) => hir::TyKind::Slice(self.lower_ty(ty, itctx)), TyKind::Ptr(mt) => hir::TyKind::Ptr(self.lower_mt(mt, itctx)), TyKind::Ref(region, mt) => { @@ -1317,6 +1281,32 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> { let lifetime = self.lower_lifetime(®ion); hir::TyKind::Ref(lifetime, self.lower_mt(mt, itctx)) } + TyKind::PinnedRef(region, mt) => { + let region = region.unwrap_or_else(|| { + let id = if let Some(LifetimeRes::ElidedAnchor { start, end }) = + self.resolver.get_lifetime_res(t.id) + { + debug_assert_eq!(start.plus(1), end); + start + } else { + self.next_node_id() + }; + let span = self.tcx.sess.source_map().start_point(t.span).shrink_to_hi(); + Lifetime { ident: Ident::new(kw::UnderscoreLifetime, span), id } + }); + let lifetime = self.lower_lifetime(®ion); + let kind = hir::TyKind::Ref(lifetime, self.lower_mt(mt, itctx)); + let span = self.lower_span(t.span); + let arg = hir::Ty { kind, span, hir_id: self.next_id() }; + let args = self.arena.alloc(hir::GenericArgs { + args: self.arena.alloc([hir::GenericArg::Type(self.arena.alloc(arg))]), + constraints: &[], + parenthesized: hir::GenericArgsParentheses::No, + span_ext: span, + }); + let path = self.make_lang_item_qpath(LangItem::Pin, span, Some(args)); + hir::TyKind::Path(path) + } TyKind::BareFn(f) => { let generic_params = self.lower_lifetime_binder(t.id, &f.generic_params); hir::TyKind::BareFn(self.arena.alloc(hir::BareFnTy { @@ -1366,16 +1356,9 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> { // We can safely ignore constness here since AST validation // takes care of rejecting invalid modifier combinations and // const trait bounds in trait object types. - GenericBound::Trait(ty, modifiers) => { - // Still, don't pass along the constness here; we don't want to - // synthesize any host effect args, it'd only cause problems. - let modifiers = TraitBoundModifiers { - constness: BoundConstness::Never, - ..*modifiers - }; - let trait_ref = this.lower_poly_trait_ref(ty, itctx, modifiers); - let polarity = this.lower_trait_bound_modifiers(modifiers); - Some((trait_ref, polarity)) + GenericBound::Trait(ty) => { + let trait_ref = this.lower_poly_trait_ref(ty, itctx); + Some(trait_ref) } GenericBound::Outlives(lifetime) => { if lifetime_bound.is_none() { @@ -1573,11 +1556,20 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> { // Feature gate for RPITIT + use<..> match origin { rustc_hir::OpaqueTyOrigin::FnReturn { in_trait_or_impl: Some(_), .. } => { - if let Some(span) = bounds.iter().find_map(|bound| match *bound { - ast::GenericBound::Use(_, span) => Some(span), - _ => None, - }) { - self.tcx.dcx().emit_err(errors::NoPreciseCapturesOnRpitit { span }); + if !self.tcx.features().precise_capturing_in_traits + && let Some(span) = bounds.iter().find_map(|bound| match *bound { + ast::GenericBound::Use(_, span) => Some(span), + _ => None, + }) + { + let mut diag = + self.tcx.dcx().create_err(errors::NoPreciseCapturesOnRpitit { span }); + add_feature_diagnostics( + &mut diag, + self.tcx.sess, + sym::precise_capturing_in_traits, + ); + diag.emit(); } } _ => {} @@ -1882,10 +1874,14 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> { // Given we are only considering `ImplicitSelf` types, we needn't consider // the case where we have a mutable pattern to a reference as that would // no longer be an `ImplicitSelf`. - TyKind::Ref(_, mt) if mt.ty.kind.is_implicit_self() => match mt.mutbl { - hir::Mutability::Not => hir::ImplicitSelfKind::RefImm, - hir::Mutability::Mut => hir::ImplicitSelfKind::RefMut, - }, + TyKind::Ref(_, mt) | TyKind::PinnedRef(_, mt) + if mt.ty.kind.is_implicit_self() => + { + match mt.mutbl { + hir::Mutability::Not => hir::ImplicitSelfKind::RefImm, + hir::Mutability::Mut => hir::ImplicitSelfKind::RefMut, + } + } _ => hir::ImplicitSelfKind::None, } }), @@ -1995,21 +1991,15 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> { span_ext: DUMMY_SP, }); - hir::GenericBound::Trait( - hir::PolyTraitRef { - bound_generic_params: &[], - trait_ref: hir::TraitRef { - path: self.make_lang_item_path( - trait_lang_item, - opaque_ty_span, - Some(bound_args), - ), - hir_ref_id: self.next_id(), - }, - span: opaque_ty_span, + hir::GenericBound::Trait(hir::PolyTraitRef { + bound_generic_params: &[], + modifiers: hir::TraitBoundModifier::None, + trait_ref: hir::TraitRef { + path: self.make_lang_item_path(trait_lang_item, opaque_ty_span, Some(bound_args)), + hir_ref_id: self.next_id(), }, - hir::TraitBoundModifier::None, - ) + span: opaque_ty_span, + }) } #[instrument(level = "trace", skip(self))] @@ -2019,10 +2009,7 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> { itctx: ImplTraitContext, ) -> hir::GenericBound<'hir> { match tpb { - GenericBound::Trait(p, modifiers) => hir::GenericBound::Trait( - self.lower_poly_trait_ref(p, itctx, *modifiers), - self.lower_trait_bound_modifiers(*modifiers), - ), + GenericBound::Trait(p) => hir::GenericBound::Trait(self.lower_poly_trait_ref(p, itctx)), GenericBound::Outlives(lifetime) => { hir::GenericBound::Outlives(self.lower_lifetime(lifetime)) } @@ -2226,12 +2213,17 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> { &mut self, p: &PolyTraitRef, itctx: ImplTraitContext, - modifiers: ast::TraitBoundModifiers, ) -> hir::PolyTraitRef<'hir> { let bound_generic_params = self.lower_lifetime_binder(p.trait_ref.ref_id, &p.bound_generic_params); - let trait_ref = self.lower_trait_ref(modifiers, &p.trait_ref, itctx); - hir::PolyTraitRef { bound_generic_params, trait_ref, span: self.lower_span(p.span) } + let trait_ref = self.lower_trait_ref(p.modifiers, &p.trait_ref, itctx); + let modifiers = self.lower_trait_bound_modifiers(p.modifiers); + hir::PolyTraitRef { + bound_generic_params, + modifiers, + trait_ref, + span: self.lower_span(p.span), + } } fn lower_mt(&mut self, mt: &MutTy, itctx: ImplTraitContext) -> hir::MutTy<'hir> { @@ -2671,10 +2663,10 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> { Res::Def(DefKind::Trait | DefKind::TraitAlias, _) => { let principal = hir::PolyTraitRef { bound_generic_params: &[], + modifiers: hir::TraitBoundModifier::None, trait_ref: hir::TraitRef { path, hir_ref_id: hir_id }, span: self.lower_span(span), }; - let principal = (principal, hir::TraitBoundModifier::None); // The original ID is taken by the `PolyTraitRef`, // so the `Ty` itself needs a different one. |