diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/librustc_resolve/build_reduced_graph.rs | 5 | ||||
| -rw-r--r-- | src/librustc_resolve/macros.rs | 80 |
2 files changed, 45 insertions, 40 deletions
diff --git a/src/librustc_resolve/build_reduced_graph.rs b/src/librustc_resolve/build_reduced_graph.rs index 423817d1be2..c5d1f63f70a 100644 --- a/src/librustc_resolve/build_reduced_graph.rs +++ b/src/librustc_resolve/build_reduced_graph.rs @@ -961,6 +961,7 @@ impl<'a, 'b, 'cl> BuildReducedGraphVisitor<'a, 'b, 'cl> { let invocation = self.resolver.invocations[&mark]; invocation.module.set(self.resolver.current_module); invocation.parent_legacy_scope.set(self.current_legacy_scope); + invocation.output_legacy_scope.set(self.current_legacy_scope); invocation } } @@ -990,7 +991,7 @@ impl<'a, 'b, 'cl> Visitor<'a> for BuildReducedGraphVisitor<'a, 'b, 'cl> { return } ItemKind::Mac(..) => { - self.current_legacy_scope = LegacyScope::Expansion(self.visit_invoc(item.id)); + self.current_legacy_scope = LegacyScope::Invocation(self.visit_invoc(item.id)); return } ItemKind::Mod(..) => self.resolver.contains_macro_use(&item.attrs), @@ -1009,7 +1010,7 @@ impl<'a, 'b, 'cl> Visitor<'a> for BuildReducedGraphVisitor<'a, 'b, 'cl> { fn visit_stmt(&mut self, stmt: &'a ast::Stmt) { if let ast::StmtKind::Mac(..) = stmt.node { - self.current_legacy_scope = LegacyScope::Expansion(self.visit_invoc(stmt.id)); + self.current_legacy_scope = LegacyScope::Invocation(self.visit_invoc(stmt.id)); } else { visit::walk_stmt(self, stmt); } diff --git a/src/librustc_resolve/macros.rs b/src/librustc_resolve/macros.rs index baff58ccee3..0359d62104c 100644 --- a/src/librustc_resolve/macros.rs +++ b/src/librustc_resolve/macros.rs @@ -50,15 +50,16 @@ crate struct FromPrelude(bool); #[derive(Clone)] pub struct InvocationData<'a> { - crate module: Cell<Module<'a>>, def_index: DefIndex, - // Legacy scope in which the macro was invoked. - // The invocation path is resolved in this scope. + /// Module in which the macro was invoked. + crate module: Cell<Module<'a>>, + /// Legacy scope in which the macro was invoked. + /// The invocation path is resolved in this scope. crate parent_legacy_scope: Cell<LegacyScope<'a>>, - // Legacy scope *produced* by expanding this macro invocation, - // includes all the macro_rules items, other invocations, etc generated by it. - // `Empty` is used if for invocations that has not been expanded yet. - output_legacy_scope: Cell<LegacyScope<'a>>, + /// Legacy scope *produced* by expanding this macro invocation, + /// includes all the macro_rules items, other invocations, etc generated by it. + /// Set to the parent scope if the macro is not expanded yet (as if the macro produced nothing). + crate output_legacy_scope: Cell<LegacyScope<'a>>, } impl<'a> InvocationData<'a> { @@ -72,21 +73,32 @@ impl<'a> InvocationData<'a> { } } -// Binding produced by a `macro_rules` item. -// Not modularized, can shadow previous legacy bindings, etc. +/// Binding produced by a `macro_rules` item. +/// Not modularized, can shadow previous legacy bindings, etc. pub struct LegacyBinding<'a> { binding: &'a NameBinding<'a>, - // Legacy scope into which the `macro_rules` item was planted. - parent_legacy_scope: Cell<LegacyScope<'a>>, + /// Legacy scope into which the `macro_rules` item was planted. + parent_legacy_scope: LegacyScope<'a>, ident: Ident, } +/// Scope introduced by a `macro_rules!` macro. +/// Starts at the macro's definition and ends at the end of the macro's parent module +/// (named or unnamed), or even further if it escapes with `#[macro_use]`. +/// Some macro invocations need to introduce legacy scopes too because they +/// potentially can expand into macro definitions. #[derive(Copy, Clone)] pub enum LegacyScope<'a> { + /// Created when invocation data is allocated in the arena, + /// must be replaced with a proper scope later. + Uninitialized, + /// Empty "root" scope at the crate start containing no names. Empty, - Invocation(&'a InvocationData<'a>), // The scope of the invocation, not including its expansion - Expansion(&'a InvocationData<'a>), // The scope of the invocation, including its expansion + /// Scope introduced by a `macro_rules!` macro definition. Binding(&'a LegacyBinding<'a>), + /// Scope introduced by a macro invocation that can potentially + /// create a `macro_rules!` macro definition. + Invocation(&'a InvocationData<'a>), } pub struct ProcMacError { @@ -181,7 +193,7 @@ impl<'a, 'crateloader: 'a> base::Resolver for Resolver<'a, 'crateloader> { } let mut visitor = BuildReducedGraphVisitor { resolver: self, - current_legacy_scope: LegacyScope::Invocation(invocation), + current_legacy_scope: invocation.parent_legacy_scope.get(), expansion: mark, }; fragment.visit_with(&mut visitor); @@ -483,8 +495,9 @@ impl<'a, 'cl> Resolver<'a, 'cl> { } } - let legacy_resolution = - self.resolve_legacy_scope(path[0], invoc_id, &invocation.parent_legacy_scope, false); + let legacy_resolution = self.resolve_legacy_scope( + path[0], invoc_id, invocation.parent_legacy_scope.get(), false + ); let result = if let Some(legacy_binding) = legacy_resolution { Ok(legacy_binding.def()) } else { @@ -788,7 +801,7 @@ impl<'a, 'cl> Resolver<'a, 'cl> { fn resolve_legacy_scope(&mut self, ident: Ident, invoc_id: Mark, - invoc_parent_legacy_scope: &'a Cell<LegacyScope<'a>>, + invoc_parent_legacy_scope: LegacyScope<'a>, record_used: bool) -> Option<&'a NameBinding<'a>> { let ident = ident.modern(); @@ -809,28 +822,18 @@ impl<'a, 'cl> Resolver<'a, 'cl> { // Go through all the scopes and try to resolve the name. let mut where_to_resolve = invoc_parent_legacy_scope; loop { - let result = match where_to_resolve.get() { + let result = match where_to_resolve { LegacyScope::Binding(legacy_binding) if ident == legacy_binding.ident => Some(legacy_binding.binding), _ => None, }; macro_rules! continue_search { () => { - where_to_resolve = match where_to_resolve.get() { + where_to_resolve = match where_to_resolve { LegacyScope::Empty => break, // nowhere else to search - LegacyScope::Binding(binding) => &binding.parent_legacy_scope, - LegacyScope::Invocation(invocation) => &invocation.parent_legacy_scope, - LegacyScope::Expansion(invocation) => { - match invocation.output_legacy_scope.get() { - LegacyScope::Empty => &invocation.parent_legacy_scope, - LegacyScope::Binding(..) | - LegacyScope::Expansion(..) => &invocation.output_legacy_scope, - LegacyScope::Invocation(..) => { - where_to_resolve.set(invocation.parent_legacy_scope.get()); - where_to_resolve - } - } - } + LegacyScope::Binding(binding) => binding.parent_legacy_scope, + LegacyScope::Invocation(invocation) => invocation.output_legacy_scope.get(), + LegacyScope::Uninitialized => unreachable!(), }; continue; @@ -885,9 +888,10 @@ impl<'a, 'cl> Resolver<'a, 'cl> { for &(invoc_id, ident, kind, def) in module.legacy_macro_resolutions.borrow().iter() { let span = ident.span; - let invoc_parent_legacy_scope = &self.invocations[&invoc_id].parent_legacy_scope; - let legacy_resolution = - self.resolve_legacy_scope(ident, invoc_id, invoc_parent_legacy_scope, true); + let invocation = self.invocations[&invoc_id]; + let legacy_resolution = self.resolve_legacy_scope( + ident, invoc_id, invocation.parent_legacy_scope.get(), true + ); let resolution = self.resolve_lexical_macro_path_segment( ident, MacroNS, invoc_id, true, true, kind == MacroKind::Attr, span ); @@ -1013,8 +1017,8 @@ impl<'a, 'cl> Resolver<'a, 'cl> { arenas.alloc_invocation_data(InvocationData { def_index: invoc.def_index, module: Cell::new(graph_root), - parent_legacy_scope: Cell::new(LegacyScope::Empty), - output_legacy_scope: Cell::new(LegacyScope::Empty), + parent_legacy_scope: Cell::new(LegacyScope::Uninitialized), + output_legacy_scope: Cell::new(LegacyScope::Uninitialized), }) }); }; @@ -1050,7 +1054,7 @@ impl<'a, 'cl> Resolver<'a, 'cl> { let vis = ty::Visibility::Invisible; // Doesn't matter for legacy bindings let binding = (def, vis, item.span, expansion).to_name_binding(self.arenas); let legacy_binding = self.arenas.alloc_legacy_binding(LegacyBinding { - parent_legacy_scope: Cell::new(*current_legacy_scope), binding, ident + parent_legacy_scope: *current_legacy_scope, binding, ident }); *current_legacy_scope = LegacyScope::Binding(legacy_binding); self.all_macros.insert(ident.name, def); |