diff options
Diffstat (limited to 'compiler/rustc_ast_lowering/src/item.rs')
| -rw-r--r-- | compiler/rustc_ast_lowering/src/item.rs | 84 |
1 files changed, 59 insertions, 25 deletions
diff --git a/compiler/rustc_ast_lowering/src/item.rs b/compiler/rustc_ast_lowering/src/item.rs index df73c721ade..7954297900f 100644 --- a/compiler/rustc_ast_lowering/src/item.rs +++ b/compiler/rustc_ast_lowering/src/item.rs @@ -90,6 +90,7 @@ impl<'a, 'hir> ItemLowerer<'a, 'hir> { allow_try_trait: Some([sym::try_trait_v2, sym::yeet_desugar_details][..].into()), allow_gen_future, generics_def_id_map: Default::default(), + host_param_id: None, }; lctx.with_hir_id_owner(owner, |lctx| f(lctx)); @@ -144,8 +145,24 @@ impl<'a, 'hir> ItemLowerer<'a, 'hir> { // This is used to track which lifetimes have already been defined, // and which need to be replicated when lowering an async fn. - if let hir::ItemKind::Impl(impl_) = parent_hir.node().expect_item().kind { - lctx.is_in_trait_impl = impl_.of_trait.is_some(); + match parent_hir.node().expect_item().kind { + hir::ItemKind::Impl(impl_) => { + lctx.is_in_trait_impl = impl_.of_trait.is_some(); + } + hir::ItemKind::Trait(_, _, generics, _, _) if lctx.tcx.features().effects => { + lctx.host_param_id = generics + .params + .iter() + .find(|param| { + parent_hir + .attrs + .get(param.hir_id.local_id) + .iter() + .any(|attr| attr.has_name(sym::rustc_host)) + }) + .map(|param| param.def_id); + } + _ => {} } match ctxt { @@ -389,6 +406,7 @@ impl<'hir> LoweringContext<'_, 'hir> { self.lower_generics(ast_generics, *constness, id, &itctx, |this| { let trait_ref = trait_ref.as_ref().map(|trait_ref| { this.lower_trait_ref( + *constness, trait_ref, &ImplTraitContext::Disallowed(ImplTraitPosition::Trait), ) @@ -419,7 +437,6 @@ impl<'hir> LoweringContext<'_, 'hir> { polarity, defaultness, defaultness_span, - constness: self.lower_constness(*constness), generics, of_trait: trait_ref, self_ty: lowered_ty, @@ -1363,6 +1380,29 @@ impl<'hir> LoweringContext<'_, 'hir> { } } + // Desugar `~const` bound in generics into an additional `const host: bool` param + // if the effects feature is enabled. This needs to be done before we lower where + // clauses since where clauses need to bind to the DefId of the host param + let host_param_parts = if let Const::Yes(span) = constness && self.tcx.features().effects { + if let Some(param) = generics.params.iter().find(|x| { + x.attrs.iter().any(|x| x.has_name(sym::rustc_host)) + }) { + // user has manually specified a `rustc_host` param, in this case, we set + // the param id so that lowering logic can use that. But we don't create + // another host param, so this gives `None`. + self.host_param_id = Some(self.local_def_id(param.id)); + None + } else { + let param_node_id = self.next_node_id(); + let hir_id = self.next_id(); + let def_id = self.create_def(self.local_def_id(parent_node_id), param_node_id, DefPathData::TypeNs(sym::host), span); + self.host_param_id = Some(def_id); + Some((span, hir_id, def_id)) + } + } else { + None + }; + let mut predicates: SmallVec<[hir::WherePredicate<'hir>; 4]> = SmallVec::new(); predicates.extend(generics.params.iter().filter_map(|param| { self.lower_generic_bound_predicate( @@ -1410,22 +1450,11 @@ 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(); + if let Some((span, hir_id, def_id)) = host_param_parts { 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 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(); @@ -1435,14 +1464,15 @@ impl<'hir> LoweringContext<'_, 'hir> { 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)))), + let attrs = self.arena.alloc_from_iter([Attribute { + kind: AttrKind::Normal(P(NormalAttr::from_ident(Ident::new( + sym::rustc_host, span, - id: attr_id, - style: AttrStyle::Outer, - }, - ]); + )))), + span, + id: attr_id, + style: AttrStyle::Outer, + }]); self.attrs.insert(hir_id.local_id, attrs); let const_body = self.lower_body(|this| { @@ -1481,7 +1511,11 @@ impl<'hir> LoweringContext<'_, 'hir> { }), )), )), - default: Some(hir::AnonConst { def_id: anon_const, hir_id: const_id, body: const_body }), + default: Some(hir::AnonConst { + def_id: anon_const, + hir_id: const_id, + body: const_body, + }), }, colon_span: None, pure_wrt_drop: false, |