diff --git a/compiler/rustc_ast/src/ast.rs b/compiler/rustc_ast/src/ast.rs index 9dfebfae5ed..f433f2eca1a 100644 --- a/compiler/rustc_ast/src/ast.rs +++ b/compiler/rustc_ast/src/ast.rs @@ -1188,14 +1188,7 @@ impl Expr { /// /// Does not ensure that the path resolves to a const param, the caller should check this. pub fn is_potential_trivial_const_arg(&self) -> bool { - let this = if let ExprKind::Block(block, None) = &self.kind - && let [stmt] = block.stmts.as_slice() - && let StmtKind::Expr(expr) = &stmt.kind - { - expr - } else { - self - }; + let this = self.maybe_unwrap_block(); if let ExprKind::Path(None, path) = &this.kind && path.is_potential_trivial_const_arg() @@ -1206,6 +1199,17 @@ impl Expr { } } + pub fn maybe_unwrap_block(&self) -> &Expr { + if let ExprKind::Block(block, None) = &self.kind + && let [stmt] = block.stmts.as_slice() + && let StmtKind::Expr(expr) = &stmt.kind + { + expr + } else { + self + } + } + pub fn to_bound(&self) -> Option { match &self.kind { ExprKind::Path(None, path) => Some(GenericBound::Trait( diff --git a/compiler/rustc_resolve/src/def_collector.rs b/compiler/rustc_resolve/src/def_collector.rs index 0fedb998463..dc1aa0a42f8 100644 --- a/compiler/rustc_resolve/src/def_collector.rs +++ b/compiler/rustc_resolve/src/def_collector.rs @@ -12,15 +12,23 @@ use rustc_span::symbol::{kw, sym, Symbol}; use rustc_span::Span; use tracing::debug; -use crate::{ImplTraitContext, Resolver}; +use crate::{ImplTraitContext, InvocationParent, PendingAnonConstInfo, Resolver}; pub(crate) fn collect_definitions( resolver: &mut Resolver<'_, '_>, fragment: &AstFragment, expansion: LocalExpnId, ) { - let (parent_def, impl_trait_context, in_attr) = resolver.invocation_parents[&expansion]; - let mut visitor = DefCollector { resolver, parent_def, expansion, impl_trait_context, in_attr }; + let InvocationParent { parent_def, pending_anon_const_info, impl_trait_context, in_attr } = + resolver.invocation_parents[&expansion]; + let mut visitor = DefCollector { + resolver, + parent_def, + pending_anon_const_info, + expansion, + impl_trait_context, + in_attr, + }; fragment.visit_with(&mut visitor); } @@ -28,6 +36,13 @@ pub(crate) fn collect_definitions( struct DefCollector<'a, 'b, 'tcx> { resolver: &'a mut Resolver<'b, 'tcx>, parent_def: LocalDefId, + /// If we have an anon const that consists of a macro invocation, e.g. `Foo<{ m!() }>`, + /// we need to wait until we know what the macro expands to before we create the def for + /// the anon const. That's because we lower some anon consts into `hir::ConstArgKind::Path`, + /// which don't have defs. + /// + /// See `Self::visit_anon_const()`. + pending_anon_const_info: Option, impl_trait_context: ImplTraitContext, in_attr: bool, expansion: LocalExpnId, @@ -111,10 +126,16 @@ impl<'a, 'b, 'tcx> DefCollector<'a, 'b, 'tcx> { fn visit_macro_invoc(&mut self, id: NodeId) { let id = id.placeholder_to_expn_id(); - let old_parent = self - .resolver - .invocation_parents - .insert(id, (self.parent_def, self.impl_trait_context, self.in_attr)); + let pending_anon_const_info = self.pending_anon_const_info.take(); + let old_parent = self.resolver.invocation_parents.insert( + id, + InvocationParent { + parent_def: self.parent_def, + pending_anon_const_info, + impl_trait_context: self.impl_trait_context, + in_attr: self.in_attr, + }, + ); assert!(old_parent.is_none(), "parent `LocalDefId` is reset for an invocation"); } } @@ -326,46 +347,67 @@ impl<'a, 'b, 'tcx> visit::Visitor<'a> for DefCollector<'a, 'b, 'tcx> { } fn visit_anon_const(&mut self, constant: &'a AnonConst) { - if self.resolver.tcx.features().const_arg_path - && constant.value.is_potential_trivial_const_arg() - { + if self.resolver.tcx.features().const_arg_path { // HACK(min_generic_const_args): don't create defs for anon consts if we think they will // later be turned into ConstArgKind::Path's. because this is before resolve is done, we // may accidentally identify a construction of a unit struct as a param and not create a // def. we'll then create a def later in ast lowering in this case. the parent of nested // items will be messed up, but that's ok because there can't be any if we're just looking // for bare idents. - visit::walk_anon_const(self, constant) - } else { - let def = - self.create_def(constant.id, kw::Empty, DefKind::AnonConst, constant.value.span); - self.with_parent(def, |this| visit::walk_anon_const(this, constant)); + + if matches!(constant.value.maybe_unwrap_block().kind, ExprKind::MacCall(..)) { + // See self.pending_anon_const_info for explanation + self.pending_anon_const_info = + Some(PendingAnonConstInfo { id: constant.id, span: constant.value.span }); + return visit::walk_anon_const(self, constant); + } else if constant.value.is_potential_trivial_const_arg() { + return visit::walk_anon_const(self, constant); + } } + + let def = self.create_def(constant.id, kw::Empty, DefKind::AnonConst, constant.value.span); + self.with_parent(def, |this| visit::walk_anon_const(this, constant)); } fn visit_expr(&mut self, expr: &'a Expr) { - let parent_def = match expr.kind { - ExprKind::MacCall(..) => return self.visit_macro_invoc(expr.id), - ExprKind::Closure(..) | ExprKind::Gen(..) => { - self.create_def(expr.id, kw::Empty, DefKind::Closure, expr.span) + if matches!(expr.kind, ExprKind::MacCall(..)) { + return self.visit_macro_invoc(expr.id); + } + + let grandparent_def = if let Some(pending_anon) = self.pending_anon_const_info.take() { + // See self.pending_anon_const_info for explanation + if !expr.is_potential_trivial_const_arg() { + self.create_def(pending_anon.id, kw::Empty, DefKind::AnonConst, pending_anon.span) + } else { + self.parent_def } - ExprKind::ConstBlock(ref constant) => { - for attr in &expr.attrs { - visit::walk_attribute(self, attr); - } - let def = self.create_def( - constant.id, - kw::Empty, - DefKind::InlineConst, - constant.value.span, - ); - self.with_parent(def, |this| visit::walk_anon_const(this, constant)); - return; - } - _ => self.parent_def, + } else { + self.parent_def }; - self.with_parent(parent_def, |this| visit::walk_expr(this, expr)); + self.with_parent(grandparent_def, |this| { + let parent_def = match expr.kind { + ExprKind::Closure(..) | ExprKind::Gen(..) => { + this.create_def(expr.id, kw::Empty, DefKind::Closure, expr.span) + } + ExprKind::ConstBlock(ref constant) => { + for attr in &expr.attrs { + visit::walk_attribute(this, attr); + } + let def = this.create_def( + constant.id, + kw::Empty, + DefKind::InlineConst, + constant.value.span, + ); + this.with_parent(def, |this| visit::walk_anon_const(this, constant)); + return; + } + _ => this.parent_def, + }; + + this.with_parent(parent_def, |this| visit::walk_expr(this, expr)) + }) } fn visit_ty(&mut self, ty: &'a Ty) { diff --git a/compiler/rustc_resolve/src/lib.rs b/compiler/rustc_resolve/src/lib.rs index 8ffd00d1b2e..6ec72649ce3 100644 --- a/compiler/rustc_resolve/src/lib.rs +++ b/compiler/rustc_resolve/src/lib.rs @@ -171,6 +171,29 @@ impl<'a> ParentScope<'a> { } } +#[derive(Copy, Debug, Clone)] +struct InvocationParent { + parent_def: LocalDefId, + pending_anon_const_info: Option, + impl_trait_context: ImplTraitContext, + in_attr: bool, +} + +impl InvocationParent { + const ROOT: Self = Self { + parent_def: CRATE_DEF_ID, + pending_anon_const_info: None, + impl_trait_context: ImplTraitContext::Existential, + in_attr: false, + }; +} + +#[derive(Copy, Debug, Clone)] +struct PendingAnonConstInfo { + id: NodeId, + span: Span, +} + #[derive(Copy, Debug, Clone)] enum ImplTraitContext { Existential, @@ -1144,7 +1167,7 @@ pub struct Resolver<'a, 'tcx> { /// When collecting definitions from an AST fragment produced by a macro invocation `ExpnId` /// we know what parent node that fragment should be attached to thanks to this table, /// and how the `impl Trait` fragments were introduced. - invocation_parents: FxHashMap, + invocation_parents: FxHashMap, /// Some way to know that we are in a *trait* impl in `visit_assoc_item`. /// FIXME: Replace with a more general AST map (together with some other fields). @@ -1381,8 +1404,7 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> { node_id_to_def_id.insert(CRATE_NODE_ID, crate_feed); let mut invocation_parents = FxHashMap::default(); - invocation_parents - .insert(LocalExpnId::ROOT, (CRATE_DEF_ID, ImplTraitContext::Existential, false)); + invocation_parents.insert(LocalExpnId::ROOT, InvocationParent::ROOT); let mut extern_prelude: FxHashMap> = tcx .sess diff --git a/compiler/rustc_resolve/src/macros.rs b/compiler/rustc_resolve/src/macros.rs index 7203fbe4a0c..d6afd01f487 100644 --- a/compiler/rustc_resolve/src/macros.rs +++ b/compiler/rustc_resolve/src/macros.rs @@ -42,9 +42,9 @@ use crate::errors::{ use crate::imports::Import; use crate::Namespace::*; use crate::{ - BindingKey, BuiltinMacroState, DeriveData, Determinacy, Finalize, MacroData, ModuleKind, - ModuleOrUniformRoot, NameBinding, NameBindingKind, ParentScope, PathResult, ResolutionError, - Resolver, ScopeSet, Segment, ToNameBinding, Used, + BindingKey, BuiltinMacroState, DeriveData, Determinacy, Finalize, InvocationParent, MacroData, + ModuleKind, ModuleOrUniformRoot, NameBinding, NameBindingKind, ParentScope, PathResult, + ResolutionError, Resolver, ScopeSet, Segment, ToNameBinding, Used, }; type Res = def::Res; @@ -183,7 +183,7 @@ impl<'a, 'tcx> ResolverExpand for Resolver<'a, 'tcx> { } fn invocation_parent(&self, id: LocalExpnId) -> LocalDefId { - self.invocation_parents[&id].0 + self.invocation_parents[&id].parent_def } fn resolve_dollar_crates(&mut self) { @@ -303,12 +303,12 @@ impl<'a, 'tcx> ResolverExpand for Resolver<'a, 'tcx> { .invocation_parents .get(&invoc_id) .or_else(|| self.invocation_parents.get(&eager_expansion_root)) - .filter(|&&(mod_def_id, _, in_attr)| { + .filter(|&&InvocationParent { parent_def: mod_def_id, in_attr, .. }| { in_attr && invoc.fragment_kind == AstFragmentKind::Expr && self.tcx.def_kind(mod_def_id) == DefKind::Mod }) - .map(|&(mod_def_id, ..)| mod_def_id); + .map(|&InvocationParent { parent_def: mod_def_id, .. }| mod_def_id); let (ext, res) = self.smart_resolve_macro_path( path, kind, @@ -951,7 +951,9 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> { let node_id = self .invocation_parents .get(&parent_scope.expansion) - .map_or(ast::CRATE_NODE_ID, |id| self.def_id_to_node_id[id.0]); + .map_or(ast::CRATE_NODE_ID, |parent| { + self.def_id_to_node_id[parent.parent_def] + }); self.lint_buffer.buffer_lint( LEGACY_DERIVE_HELPERS, node_id,