1 //! After we obtain a fresh AST fragment from a macro, code in this module helps to integrate
2 //! that fragment into the module structures that are already partially built.
4 //! Items from the fragment are placed into modules,
5 //! unexpanded macros in the fragment are visited and registered.
6 //! Imports are also considered items and placed into modules here, but not resolved yet.
8 use crate::def_collector::collect_definitions;
9 use crate::imports::{Import, ImportKind};
10 use crate::macros::{MacroRulesBinding, MacroRulesScope, MacroRulesScopeRef};
11 use crate::Namespace::{self, MacroNS, TypeNS, ValueNS};
12 use crate::{Determinacy, ExternPreludeEntry, Finalize, Module, ModuleKind, ModuleOrUniformRoot};
14 MacroData, NameBinding, NameBindingKind, ParentScope, PathResult, PerNS, ResolutionError,
16 use crate::{Resolver, ResolverArenas, Segment, ToNameBinding, VisResolutionError};
18 use rustc_ast::visit::{self, AssocCtxt, Visitor};
19 use rustc_ast::{self as ast, AssocItem, AssocItemKind, MetaItemKind, StmtKind};
20 use rustc_ast::{Block, Fn, ForeignItem, ForeignItemKind, Impl, Item, ItemKind, NodeId};
21 use rustc_attr as attr;
22 use rustc_data_structures::sync::Lrc;
23 use rustc_errors::{struct_span_err, Applicability};
24 use rustc_expand::expand::AstFragment;
25 use rustc_hir::def::{self, *};
26 use rustc_hir::def_id::{DefId, LocalDefId, CRATE_DEF_ID};
27 use rustc_metadata::creader::LoadedMacro;
28 use rustc_middle::bug;
29 use rustc_middle::metadata::ModChild;
30 use rustc_middle::ty::{self, DefIdTree};
31 use rustc_session::cstore::CrateStore;
32 use rustc_span::hygiene::{ExpnId, LocalExpnId, MacroKind};
33 use rustc_span::source_map::{respan, Spanned};
34 use rustc_span::symbol::{kw, sym, Ident, Symbol};
40 type Res = def::Res<NodeId>;
42 impl<'a> ToNameBinding<'a> for (Module<'a>, ty::Visibility, Span, LocalExpnId) {
43 fn to_name_binding(self, arenas: &'a ResolverArenas<'a>) -> &'a NameBinding<'a> {
44 arenas.alloc_name_binding(NameBinding {
45 kind: NameBindingKind::Module(self.0),
54 impl<'a> ToNameBinding<'a> for (Res, ty::Visibility, Span, LocalExpnId) {
55 fn to_name_binding(self, arenas: &'a ResolverArenas<'a>) -> &'a NameBinding<'a> {
56 arenas.alloc_name_binding(NameBinding {
57 kind: NameBindingKind::Res(self.0, false),
68 impl<'a> ToNameBinding<'a> for (Res, ty::Visibility, Span, LocalExpnId, IsMacroExport) {
69 fn to_name_binding(self, arenas: &'a ResolverArenas<'a>) -> &'a NameBinding<'a> {
70 arenas.alloc_name_binding(NameBinding {
71 kind: NameBindingKind::Res(self.0, true),
80 impl<'a> Resolver<'a> {
81 /// Defines `name` in namespace `ns` of module `parent` to be `def` if it is not yet defined;
82 /// otherwise, reports an error.
83 pub(crate) fn define<T>(&mut self, parent: Module<'a>, ident: Ident, ns: Namespace, def: T)
87 let binding = def.to_name_binding(self.arenas);
88 let key = self.new_key(ident, ns);
89 if let Err(old_binding) = self.try_define(parent, key, binding) {
90 self.report_conflict(parent, ident, ns, old_binding, &binding);
94 /// Walks up the tree of definitions starting at `def_id`,
95 /// stopping at the first encountered module.
96 /// Parent block modules for arbitrary def-ids are not recorded for the local crate,
97 /// and are not preserved in metadata for foreign crates, so block modules are never
98 /// returned by this function.
100 /// For the local crate ignoring block modules may be incorrect, so use this method with care.
102 /// For foreign crates block modules can be ignored without introducing observable differences,
103 /// moreover they has to be ignored right now because they are not kept in metadata.
104 /// Foreign parent modules are used for resolving names used by foreign macros with def-site
105 /// hygiene, therefore block module ignorability relies on macros with def-site hygiene and
106 /// block module parents being unreachable from other crates.
107 /// Reachable macros with block module parents exist due to `#[macro_export] macro_rules!`,
108 /// but they cannot use def-site hygiene, so the assumption holds
109 /// (<https://github.com/rust-lang/rust/pull/77984#issuecomment-712445508>).
110 pub fn get_nearest_non_block_module(&mut self, mut def_id: DefId) -> Module<'a> {
112 match self.get_module(def_id) {
113 Some(module) => return module,
114 None => def_id = self.parent(def_id),
119 pub fn expect_module(&mut self, def_id: DefId) -> Module<'a> {
120 self.get_module(def_id).expect("argument `DefId` is not a module")
123 /// If `def_id` refers to a module (in resolver's sense, i.e. a module item, crate root, enum,
124 /// or trait), then this function returns that module's resolver representation, otherwise it
126 pub(crate) fn get_module(&mut self, def_id: DefId) -> Option<Module<'a>> {
127 if let module @ Some(..) = self.module_map.get(&def_id) {
128 return module.copied();
131 if !def_id.is_local() {
132 let def_kind = self.cstore().def_kind(def_id);
134 DefKind::Mod | DefKind::Enum | DefKind::Trait => {
135 let def_key = self.cstore().def_key(def_id);
136 let parent = def_key.parent.map(|index| {
137 self.get_nearest_non_block_module(DefId { index, krate: def_id.krate })
139 let name = if let Some(cnum) = def_id.as_crate_root() {
140 self.cstore().crate_name(cnum)
142 def_key.disambiguated_data.data.get_opt_name().expect("module without name")
145 Some(self.new_module(
147 ModuleKind::Def(def_kind, def_id, name),
148 self.cstore().module_expansion_untracked(def_id, &self.session),
149 self.cstore().get_span_untracked(def_id, &self.session),
150 // FIXME: Account for `#[no_implicit_prelude]` attributes.
151 parent.map_or(false, |module| module.no_implicit_prelude),
161 pub(crate) fn expn_def_scope(&mut self, expn_id: ExpnId) -> Module<'a> {
162 match expn_id.expn_data().macro_def_id {
163 Some(def_id) => self.macro_def_scope(def_id),
166 .and_then(|expn_id| self.ast_transform_scopes.get(&expn_id))
167 .unwrap_or(&self.graph_root),
171 pub(crate) fn macro_def_scope(&mut self, def_id: DefId) -> Module<'a> {
172 if let Some(id) = def_id.as_local() {
173 self.local_macro_def_scopes[&id]
175 self.get_nearest_non_block_module(def_id)
179 pub(crate) fn get_macro(&mut self, res: Res) -> Option<MacroData> {
181 Res::Def(DefKind::Macro(..), def_id) => Some(self.get_macro_by_def_id(def_id)),
182 Res::NonMacroAttr(_) => {
183 Some(MacroData { ext: self.non_macro_attr.clone(), macro_rules: false })
189 pub(crate) fn get_macro_by_def_id(&mut self, def_id: DefId) -> MacroData {
190 if let Some(macro_data) = self.macro_map.get(&def_id) {
191 return macro_data.clone();
194 let (ext, macro_rules) = match self.cstore().load_macro_untracked(def_id, &self.session) {
195 LoadedMacro::MacroDef(item, edition) => (
196 Lrc::new(self.compile_macro(&item, edition).0),
197 matches!(item.kind, ItemKind::MacroDef(def) if def.macro_rules),
199 LoadedMacro::ProcMacro(extz) => (Lrc::new(extz), false),
202 let macro_data = MacroData { ext, macro_rules };
203 self.macro_map.insert(def_id, macro_data.clone());
207 pub(crate) fn build_reduced_graph(
209 fragment: &AstFragment,
210 parent_scope: ParentScope<'a>,
211 ) -> MacroRulesScopeRef<'a> {
212 collect_definitions(self, fragment, parent_scope.expansion);
213 let mut visitor = BuildReducedGraphVisitor { r: self, parent_scope };
214 fragment.visit_with(&mut visitor);
215 visitor.parent_scope.macro_rules
218 pub(crate) fn build_reduced_graph_external(&mut self, module: Module<'a>) {
219 for child in self.cstore().module_children_untracked(module.def_id(), self.session) {
220 let parent_scope = ParentScope::module(module, self);
221 BuildReducedGraphVisitor { r: self, parent_scope }
222 .build_reduced_graph_for_external_crate_res(child);
227 struct BuildReducedGraphVisitor<'a, 'b> {
228 r: &'b mut Resolver<'a>,
229 parent_scope: ParentScope<'a>,
232 impl<'a> AsMut<Resolver<'a>> for BuildReducedGraphVisitor<'a, '_> {
233 fn as_mut(&mut self) -> &mut Resolver<'a> {
238 impl<'a, 'b> BuildReducedGraphVisitor<'a, 'b> {
239 fn resolve_visibility(&mut self, vis: &ast::Visibility) -> ty::Visibility {
240 self.try_resolve_visibility(vis, true).unwrap_or_else(|err| {
241 self.r.report_vis_error(err);
242 ty::Visibility::Public
246 fn try_resolve_visibility<'ast>(
248 vis: &'ast ast::Visibility,
250 ) -> Result<ty::Visibility, VisResolutionError<'ast>> {
251 let parent_scope = &self.parent_scope;
253 ast::VisibilityKind::Public => Ok(ty::Visibility::Public),
254 ast::VisibilityKind::Inherited => {
255 Ok(match self.parent_scope.module.kind {
256 // Any inherited visibility resolved directly inside an enum or trait
257 // (i.e. variants, fields, and trait items) inherits from the visibility
258 // of the enum or trait.
259 ModuleKind::Def(DefKind::Enum | DefKind::Trait, def_id, _) => {
260 self.r.visibilities[&def_id.expect_local()]
262 // Otherwise, the visibility is restricted to the nearest parent `mod` item.
263 _ => ty::Visibility::Restricted(self.parent_scope.module.nearest_parent_mod()),
266 ast::VisibilityKind::Restricted { ref path, id, .. } => {
267 // Make `PRIVATE_IN_PUBLIC` lint a hard error.
268 self.r.has_pub_restricted = true;
269 // For visibilities we are not ready to provide correct implementation of "uniform
270 // paths" right now, so on 2018 edition we only allow module-relative paths for now.
271 // On 2015 edition visibilities are resolved as crate-relative by default,
272 // so we are prepending a root segment if necessary.
273 let ident = path.segments.get(0).expect("empty path in visibility").ident;
274 let crate_root = if ident.is_path_segment_keyword() {
276 } else if ident.span.rust_2015() {
277 Some(Segment::from_ident(Ident::new(
279 path.span.shrink_to_lo().with_ctxt(ident.span.ctxt()),
282 return Err(VisResolutionError::Relative2018(ident.span, path));
285 let segments = crate_root
287 .chain(path.segments.iter().map(|seg| seg.into()))
288 .collect::<Vec<_>>();
289 let expected_found_error = |res| {
290 Err(VisResolutionError::ExpectedFound(
292 Segment::names_to_string(&segments),
296 match self.r.resolve_path(
300 finalize.then(|| Finalize::new(id, path.span)),
303 PathResult::Module(ModuleOrUniformRoot::Module(module)) => {
304 let res = module.res().expect("visibility resolved to unnamed block");
306 self.r.record_partial_res(id, PartialRes::new(res));
308 if module.is_normal() {
310 Ok(ty::Visibility::Public)
312 let vis = ty::Visibility::Restricted(res.def_id());
313 if self.r.is_accessible_from(vis, parent_scope.module) {
316 Err(VisResolutionError::AncestorOnly(path.span))
320 expected_found_error(res)
323 PathResult::Module(..) => Err(VisResolutionError::ModuleOnly(path.span)),
324 PathResult::NonModule(partial_res) => {
325 expected_found_error(partial_res.base_res())
327 PathResult::Failed { span, label, suggestion, .. } => {
328 Err(VisResolutionError::FailedToResolve(span, label, suggestion))
330 PathResult::Indeterminate => Err(VisResolutionError::Indeterminate(path.span)),
336 fn insert_field_names_local(&mut self, def_id: DefId, vdata: &ast::VariantData) {
337 let field_names = vdata
340 .map(|field| respan(field.span, field.ident.map_or(kw::Empty, |ident| ident.name)))
342 self.insert_field_names(def_id, field_names);
345 fn insert_field_names(&mut self, def_id: DefId, field_names: Vec<Spanned<Symbol>>) {
346 self.r.field_names.insert(def_id, field_names);
349 fn block_needs_anonymous_module(&mut self, block: &Block) -> bool {
350 // If any statements are items, we need to create an anonymous module
354 .any(|statement| matches!(statement.kind, StmtKind::Item(_) | StmtKind::MacCall(_)))
357 // Add an import to the current module.
360 module_path: Vec<Segment>,
361 kind: ImportKind<'a>,
369 let current_module = self.parent_scope.module;
370 let import = self.r.arenas.alloc_import(Import {
372 parent_scope: self.parent_scope,
374 imported_module: Cell::new(None),
378 use_span_with_attributes: item.span_with_attributes(),
379 has_attributes: !item.attrs.is_empty(),
382 vis: Cell::new(Some(vis)),
383 used: Cell::new(false),
386 self.r.indeterminate_imports.push(import);
388 // Don't add unresolved underscore imports to modules
389 ImportKind::Single { target: Ident { name: kw::Underscore, .. }, .. } => {}
390 ImportKind::Single { target, type_ns_only, .. } => {
391 self.r.per_ns(|this, ns| {
392 if !type_ns_only || ns == TypeNS {
393 let key = this.new_key(target, ns);
394 let mut resolution = this.resolution(current_module, key).borrow_mut();
395 resolution.add_single_import(import);
399 // We don't add prelude imports to the globs since they only affect lexical scopes,
400 // which are not relevant to import resolution.
401 ImportKind::Glob { is_prelude: true, .. } => {}
402 ImportKind::Glob { .. } => current_module.globs.borrow_mut().push(import),
407 fn build_reduced_graph_for_use_tree(
409 // This particular use tree
410 use_tree: &ast::UseTree,
412 parent_prefix: &[Segment],
414 // The whole `use` item
420 "build_reduced_graph_for_use_tree(parent_prefix={:?}, use_tree={:?}, nested={})",
421 parent_prefix, use_tree, nested
424 let mut prefix_iter = parent_prefix
427 .chain(use_tree.prefix.segments.iter().map(|seg| seg.into()))
430 // On 2015 edition imports are resolved as crate-relative by default,
431 // so prefixes are prepended with crate root segment if necessary.
432 // The root is prepended lazily, when the first non-empty prefix or terminating glob
433 // appears, so imports in braced groups can have roots prepended independently.
434 let is_glob = matches!(use_tree.kind, ast::UseTreeKind::Glob);
435 let crate_root = match prefix_iter.peek() {
436 Some(seg) if !seg.ident.is_path_segment_keyword() && seg.ident.span.rust_2015() => {
437 Some(seg.ident.span.ctxt())
439 None if is_glob && use_tree.span.rust_2015() => Some(use_tree.span.ctxt()),
443 Segment::from_ident(Ident::new(
445 use_tree.prefix.span.shrink_to_lo().with_ctxt(ctxt),
449 let prefix = crate_root.into_iter().chain(prefix_iter).collect::<Vec<_>>();
450 debug!("build_reduced_graph_for_use_tree: prefix={:?}", prefix);
452 let empty_for_self = |prefix: &[Segment]| {
453 prefix.is_empty() || prefix.len() == 1 && prefix[0].ident.name == kw::PathRoot
455 match use_tree.kind {
456 ast::UseTreeKind::Simple(rename, id1, id2) => {
457 let mut ident = use_tree.ident();
458 let mut module_path = prefix;
459 let mut source = module_path.pop().unwrap();
460 let mut type_ns_only = false;
462 self.r.visibilities.insert(self.r.local_def_id(id), vis);
463 if id1 != ast::DUMMY_NODE_ID {
464 self.r.visibilities.insert(self.r.local_def_id(id1), vis);
466 if id2 != ast::DUMMY_NODE_ID {
467 self.r.visibilities.insert(self.r.local_def_id(id2), vis);
471 // Correctly handle `self`
472 if source.ident.name == kw::SelfLower {
475 if empty_for_self(&module_path) {
478 ResolutionError::SelfImportOnlyInImportListWithNonEmptyPrefix,
483 // Replace `use foo::{ self };` with `use foo;`
484 source = module_path.pop().unwrap();
485 if rename.is_none() {
486 ident = source.ident;
491 if source.ident.name == kw::SelfLower {
492 let parent = module_path.last();
494 let span = match parent {
495 // only `::self` from `use foo::self as bar`
496 Some(seg) => seg.ident.span.shrink_to_hi().to(source.ident.span),
497 None => source.ident.span,
499 let span_with_rename = match rename {
500 // only `self as bar` from `use foo::self as bar`
501 Some(rename) => source.ident.span.to(rename.span),
502 None => source.ident.span,
506 ResolutionError::SelfImportsOnlyAllowedWithin {
507 root: parent.is_none(),
512 // Error recovery: replace `use foo::self;` with `use foo;`
513 if let Some(parent) = module_path.pop() {
515 if rename.is_none() {
516 ident = source.ident;
521 // Disallow `use $crate;`
522 if source.ident.name == kw::DollarCrate && module_path.is_empty() {
523 let crate_root = self.r.resolve_crate_root(source.ident);
524 let crate_name = match crate_root.kind {
525 ModuleKind::Def(.., name) => name,
526 ModuleKind::Block => unreachable!(),
528 // HACK(eddyb) unclear how good this is, but keeping `$crate`
529 // in `source` breaks `src/test/ui/imports/import-crate-var.rs`,
530 // while the current crate doesn't have a valid `crate_name`.
531 if crate_name != kw::Empty {
532 // `crate_name` should not be interpreted as relative.
533 module_path.push(Segment::from_ident_and_id(
534 Ident { name: kw::PathRoot, span: source.ident.span },
535 self.r.next_node_id(),
537 source.ident.name = crate_name;
539 if rename.is_none() {
540 ident.name = crate_name;
545 .struct_span_err(item.span, "`$crate` may not be imported")
550 if ident.name == kw::Crate {
551 self.r.session.span_err(
553 "crate root imports need to be explicitly named: \
554 `use crate as name;`",
558 let kind = ImportKind::Single {
559 source: source.ident,
561 source_bindings: PerNS {
562 type_ns: Cell::new(Err(Determinacy::Undetermined)),
563 value_ns: Cell::new(Err(Determinacy::Undetermined)),
564 macro_ns: Cell::new(Err(Determinacy::Undetermined)),
566 target_bindings: PerNS {
567 type_ns: Cell::new(None),
568 value_ns: Cell::new(None),
569 macro_ns: Cell::new(None),
573 additional_ids: (id1, id2),
587 ast::UseTreeKind::Glob => {
588 let kind = ImportKind::Glob {
589 is_prelude: self.r.session.contains_name(&item.attrs, sym::prelude_import),
590 max_vis: Cell::new(None),
592 self.r.visibilities.insert(self.r.local_def_id(id), vis);
593 self.add_import(prefix, kind, use_tree.span, id, item, root_span, item.id, vis);
595 ast::UseTreeKind::Nested(ref items) => {
596 // Ensure there is at most one `self` in the list
597 let self_spans = items
599 .filter_map(|&(ref use_tree, _)| {
600 if let ast::UseTreeKind::Simple(..) = use_tree.kind {
601 if use_tree.ident().name == kw::SelfLower {
602 return Some(use_tree.span);
608 .collect::<Vec<_>>();
609 if self_spans.len() > 1 {
610 let mut e = self.r.into_struct_error(
612 ResolutionError::SelfImportCanOnlyAppearOnceInTheList,
615 for other_span in self_spans.iter().skip(1) {
616 e.span_label(*other_span, "another `self` import appears here");
622 for &(ref tree, id) in items {
623 self.build_reduced_graph_for_use_tree(
624 // This particular use tree
625 tree, id, &prefix, true, // The whole `use` item
626 item, vis, root_span,
630 // Empty groups `a::b::{}` are turned into synthetic `self` imports
631 // `a::b::c::{self as _}`, so that their prefixes are correctly
632 // resolved and checked for privacy/stability/etc.
633 if items.is_empty() && !empty_for_self(&prefix) {
634 let new_span = prefix[prefix.len() - 1].ident.span;
635 let tree = ast::UseTree {
636 prefix: ast::Path::from_ident(Ident::new(kw::SelfLower, new_span)),
637 kind: ast::UseTreeKind::Simple(
638 Some(Ident::new(kw::Underscore, new_span)),
644 self.build_reduced_graph_for_use_tree(
645 // This particular use tree
650 // The whole `use` item
652 ty::Visibility::Restricted(self.parent_scope.module.nearest_parent_mod()),
660 /// Constructs the reduced graph for one item.
661 fn build_reduced_graph_for_item(&mut self, item: &'b Item) {
662 let parent_scope = &self.parent_scope;
663 let parent = parent_scope.module;
664 let expansion = parent_scope.expansion;
665 let ident = item.ident;
667 let vis = self.resolve_visibility(&item.vis);
668 let local_def_id = self.r.local_def_id(item.id);
669 let def_id = local_def_id.to_def_id();
671 self.r.visibilities.insert(local_def_id, vis);
674 ItemKind::Use(ref use_tree) => {
675 self.build_reduced_graph_for_use_tree(
676 // This particular use tree
681 // The whole `use` item
688 ItemKind::ExternCrate(orig_name) => {
689 self.build_reduced_graph_for_extern_crate(
698 ItemKind::Mod(..) => {
699 let module = self.r.new_module(
701 ModuleKind::Def(DefKind::Mod, def_id, ident.name),
702 expansion.to_expn_id(),
704 parent.no_implicit_prelude
705 || self.r.session.contains_name(&item.attrs, sym::no_implicit_prelude),
707 self.r.define(parent, ident, TypeNS, (module, vis, sp, expansion));
709 // Descend into the module.
710 self.parent_scope.module = module;
713 // These items live in the value namespace.
714 ItemKind::Static(_, mt, _) => {
715 let res = Res::Def(DefKind::Static(mt), def_id);
716 self.r.define(parent, ident, ValueNS, (res, vis, sp, expansion));
718 ItemKind::Const(..) => {
719 let res = Res::Def(DefKind::Const, def_id);
720 self.r.define(parent, ident, ValueNS, (res, vis, sp, expansion));
722 ItemKind::Fn(..) => {
723 let res = Res::Def(DefKind::Fn, def_id);
724 self.r.define(parent, ident, ValueNS, (res, vis, sp, expansion));
726 // Functions introducing procedural macros reserve a slot
727 // in the macro namespace as well (see #52225).
728 self.define_macro(item);
731 // These items live in the type namespace.
732 ItemKind::TyAlias(..) => {
733 let res = Res::Def(DefKind::TyAlias, def_id);
734 self.r.define(parent, ident, TypeNS, (res, vis, sp, expansion));
737 ItemKind::Enum(_, _) => {
738 let module = self.r.new_module(
740 ModuleKind::Def(DefKind::Enum, def_id, ident.name),
741 expansion.to_expn_id(),
743 parent.no_implicit_prelude,
745 self.r.define(parent, ident, TypeNS, (module, vis, sp, expansion));
746 self.parent_scope.module = module;
749 ItemKind::TraitAlias(..) => {
750 let res = Res::Def(DefKind::TraitAlias, def_id);
751 self.r.define(parent, ident, TypeNS, (res, vis, sp, expansion));
754 // These items live in both the type and value namespaces.
755 ItemKind::Struct(ref vdata, _) => {
756 // Define a name in the type namespace.
757 let res = Res::Def(DefKind::Struct, def_id);
758 self.r.define(parent, ident, TypeNS, (res, vis, sp, expansion));
760 // Record field names for error reporting.
761 self.insert_field_names_local(def_id, vdata);
763 // If this is a tuple or unit struct, define a name
764 // in the value namespace as well.
765 if let Some(ctor_node_id) = vdata.ctor_id() {
766 // If the structure is marked as non_exhaustive then lower the visibility
767 // to within the crate.
768 let mut ctor_vis = if vis == ty::Visibility::Public
769 && self.r.session.contains_name(&item.attrs, sym::non_exhaustive)
771 ty::Visibility::Restricted(CRATE_DEF_ID.to_def_id())
776 let mut ret_fields = Vec::with_capacity(vdata.fields().len());
778 for field in vdata.fields() {
779 // NOTE: The field may be an expansion placeholder, but expansion sets
780 // correct visibilities for unnamed field placeholders specifically, so the
781 // constructor visibility should still be determined correctly.
783 .try_resolve_visibility(&field.vis, false)
784 .unwrap_or(ty::Visibility::Public);
785 if ctor_vis.is_at_least(field_vis, &*self.r) {
786 ctor_vis = field_vis;
788 ret_fields.push(field_vis);
790 let ctor_def_id = self.r.local_def_id(ctor_node_id);
791 let ctor_res = Res::Def(
792 DefKind::Ctor(CtorOf::Struct, CtorKind::from_ast(vdata)),
793 ctor_def_id.to_def_id(),
795 self.r.define(parent, ident, ValueNS, (ctor_res, ctor_vis, sp, expansion));
796 self.r.visibilities.insert(ctor_def_id, ctor_vis);
798 self.r.struct_constructors.insert(def_id, (ctor_res, ctor_vis, ret_fields));
802 ItemKind::Union(ref vdata, _) => {
803 let res = Res::Def(DefKind::Union, def_id);
804 self.r.define(parent, ident, TypeNS, (res, vis, sp, expansion));
806 // Record field names for error reporting.
807 self.insert_field_names_local(def_id, vdata);
810 ItemKind::Trait(..) => {
811 // Add all the items within to a new module.
812 let module = self.r.new_module(
814 ModuleKind::Def(DefKind::Trait, def_id, ident.name),
815 expansion.to_expn_id(),
817 parent.no_implicit_prelude,
819 self.r.define(parent, ident, TypeNS, (module, vis, sp, expansion));
820 self.parent_scope.module = module;
823 // These items do not add names to modules.
824 ItemKind::Impl(box Impl { of_trait: Some(..), .. }) => {
825 self.r.trait_impl_items.insert(local_def_id);
827 ItemKind::Impl { .. } | ItemKind::ForeignMod(..) | ItemKind::GlobalAsm(..) => {}
829 ItemKind::MacroDef(..) | ItemKind::MacCall(_) => unreachable!(),
833 fn build_reduced_graph_for_extern_crate(
835 orig_name: Option<Symbol>,
837 local_def_id: LocalDefId,
841 let ident = item.ident;
843 let parent_scope = self.parent_scope;
844 let expansion = parent_scope.expansion;
846 let (used, module, binding) = if orig_name.is_none() && ident.name == kw::SelfLower {
849 .struct_span_err(item.span, "`extern crate self;` requires renaming")
852 "rename the `self` crate to be able to import it",
853 "extern crate self as name;",
854 Applicability::HasPlaceholders,
858 } else if orig_name == Some(kw::SelfLower) {
859 Some(self.r.graph_root)
861 self.r.crate_loader.process_extern_crate(item, &self.r.definitions, local_def_id).map(
863 self.r.extern_crate_map.insert(local_def_id, crate_id);
864 self.r.expect_module(crate_id.as_def_id())
869 let used = self.process_macro_use_imports(item, module);
871 (module, ty::Visibility::Public, sp, expansion).to_name_binding(self.r.arenas);
872 (used, Some(ModuleOrUniformRoot::Module(module)), binding)
874 .unwrap_or((true, None, self.r.dummy_binding));
875 let import = self.r.arenas.alloc_import(Import {
876 kind: ImportKind::ExternCrate { source: orig_name, target: ident },
879 parent_scope: self.parent_scope,
880 imported_module: Cell::new(module),
881 has_attributes: !item.attrs.is_empty(),
882 use_span_with_attributes: item.span_with_attributes(),
884 root_span: item.span,
886 module_path: Vec::new(),
887 vis: Cell::new(Some(vis)),
888 used: Cell::new(used),
890 self.r.potentially_unused_imports.push(import);
891 let imported_binding = self.r.import(binding, import);
892 if ptr::eq(parent, self.r.graph_root) {
893 if let Some(entry) = self.r.extern_prelude.get(&ident.normalize_to_macros_2_0()) {
894 if expansion != LocalExpnId::ROOT
895 && orig_name.is_some()
896 && entry.extern_crate_item.is_none()
898 let msg = "macro-expanded `extern crate` items cannot \
899 shadow names passed with `--extern`";
900 self.r.session.span_err(item.span, msg);
903 let entry = self.r.extern_prelude.entry(ident.normalize_to_macros_2_0()).or_insert(
904 ExternPreludeEntry { extern_crate_item: None, introduced_by_item: true },
906 entry.extern_crate_item = Some(imported_binding);
907 if orig_name.is_some() {
908 entry.introduced_by_item = true;
911 self.r.define(parent, ident, TypeNS, imported_binding);
914 /// Constructs the reduced graph for one foreign item.
915 fn build_reduced_graph_for_foreign_item(&mut self, item: &ForeignItem) {
916 let local_def_id = self.r.local_def_id(item.id);
917 let def_id = local_def_id.to_def_id();
918 let (def_kind, ns) = match item.kind {
919 ForeignItemKind::Fn(..) => (DefKind::Fn, ValueNS),
920 ForeignItemKind::Static(_, mt, _) => (DefKind::Static(mt), ValueNS),
921 ForeignItemKind::TyAlias(..) => (DefKind::ForeignTy, TypeNS),
922 ForeignItemKind::MacCall(_) => unreachable!(),
924 let parent = self.parent_scope.module;
925 let expansion = self.parent_scope.expansion;
926 let vis = self.resolve_visibility(&item.vis);
927 let res = Res::Def(def_kind, def_id);
928 self.r.define(parent, item.ident, ns, (res, vis, item.span, expansion));
929 self.r.visibilities.insert(local_def_id, vis);
932 fn build_reduced_graph_for_block(&mut self, block: &Block) {
933 let parent = self.parent_scope.module;
934 let expansion = self.parent_scope.expansion;
935 if self.block_needs_anonymous_module(block) {
936 let module = self.r.new_module(
939 expansion.to_expn_id(),
941 parent.no_implicit_prelude,
943 self.r.block_map.insert(block.id, module);
944 self.parent_scope.module = module; // Descend into the block.
948 /// Builds the reduced graph for a single item in an external crate.
949 fn build_reduced_graph_for_external_crate_res(&mut self, child: ModChild) {
950 let parent = self.parent_scope.module;
951 let ModChild { ident, res, vis, span, macro_rules } = child;
952 let res = res.expect_non_local();
953 let expansion = self.parent_scope.expansion;
954 // Record primary definitions.
956 Res::Def(DefKind::Mod | DefKind::Enum | DefKind::Trait, def_id) => {
957 let module = self.r.expect_module(def_id);
958 self.r.define(parent, ident, TypeNS, (module, vis, span, expansion));
967 | DefKind::TraitAlias
972 | Res::ToolMod => self.r.define(parent, ident, TypeNS, (res, vis, span, expansion)),
978 | DefKind::AssocConst
981 ) => self.r.define(parent, ident, ValueNS, (res, vis, span, expansion)),
982 Res::Def(DefKind::Macro(..), _) | Res::NonMacroAttr(..) => {
984 self.r.define(parent, ident, MacroNS, (res, vis, span, expansion))
989 | DefKind::ConstParam
990 | DefKind::ExternCrate
992 | DefKind::ForeignMod
994 | DefKind::InlineConst
996 | DefKind::LifetimeParam
1000 | DefKind::Generator,
1004 | Res::SelfTy { .. }
1006 | Res::Err => bug!("unexpected resolution: {:?}", res),
1008 // Record some extra data for better diagnostics.
1009 let cstore = self.r.cstore();
1011 Res::Def(DefKind::Struct, def_id) => {
1013 cstore.struct_field_names_untracked(def_id, self.r.session).collect();
1014 let ctor = cstore.ctor_def_id_and_kind_untracked(def_id);
1015 if let Some((ctor_def_id, ctor_kind)) = ctor {
1016 let ctor_res = Res::Def(DefKind::Ctor(CtorOf::Struct, ctor_kind), ctor_def_id);
1017 let ctor_vis = cstore.visibility_untracked(ctor_def_id);
1018 let field_visibilities =
1019 cstore.struct_field_visibilities_untracked(def_id).collect();
1021 .struct_constructors
1022 .insert(def_id, (ctor_res, ctor_vis, field_visibilities));
1024 self.insert_field_names(def_id, field_names);
1026 Res::Def(DefKind::Union, def_id) => {
1028 cstore.struct_field_names_untracked(def_id, self.r.session).collect();
1029 self.insert_field_names(def_id, field_names);
1031 Res::Def(DefKind::AssocFn, def_id) => {
1032 if cstore.fn_has_self_parameter_untracked(def_id) {
1033 self.r.has_self.insert(def_id);
1040 fn add_macro_use_binding(
1043 binding: &'a NameBinding<'a>,
1045 allow_shadowing: bool,
1047 if self.r.macro_use_prelude.insert(name, binding).is_some() && !allow_shadowing {
1048 let msg = format!("`{}` is already in scope", name);
1050 "macro-expanded `#[macro_use]`s may not shadow existing macros (see RFC 1560)";
1051 self.r.session.struct_span_err(span, &msg).note(note).emit();
1055 /// Returns `true` if we should consider the underlying `extern crate` to be used.
1056 fn process_macro_use_imports(&mut self, item: &Item, module: Module<'a>) -> bool {
1057 let mut import_all = None;
1058 let mut single_imports = Vec::new();
1059 for attr in &item.attrs {
1060 if attr.has_name(sym::macro_use) {
1061 if self.parent_scope.module.parent.is_some() {
1066 "an `extern crate` loading macros must be at the crate root"
1070 if let ItemKind::ExternCrate(Some(orig_name)) = item.kind {
1071 if orig_name == kw::SelfLower {
1076 "`#[macro_use]` is not supported on `extern crate self`",
1081 let ill_formed = |span| {
1082 struct_span_err!(self.r.session, span, E0466, "bad macro import").emit();
1085 Some(meta) => match meta.kind {
1086 MetaItemKind::Word => {
1087 import_all = Some(meta.span);
1090 MetaItemKind::List(nested_metas) => {
1091 for nested_meta in nested_metas {
1092 match nested_meta.ident() {
1093 Some(ident) if nested_meta.is_word() => {
1094 single_imports.push(ident)
1096 _ => ill_formed(nested_meta.span()),
1100 MetaItemKind::NameValue(..) => ill_formed(meta.span),
1102 None => ill_formed(attr.span),
1107 let macro_use_import = |this: &Self, span| {
1108 this.r.arenas.alloc_import(Import {
1109 kind: ImportKind::MacroUse,
1112 parent_scope: this.parent_scope,
1113 imported_module: Cell::new(Some(ModuleOrUniformRoot::Module(module))),
1114 use_span_with_attributes: item.span_with_attributes(),
1115 has_attributes: !item.attrs.is_empty(),
1116 use_span: item.span,
1119 module_path: Vec::new(),
1120 vis: Cell::new(Some(ty::Visibility::Restricted(CRATE_DEF_ID.to_def_id()))),
1121 used: Cell::new(false),
1125 let allow_shadowing = self.parent_scope.expansion == LocalExpnId::ROOT;
1126 if let Some(span) = import_all {
1127 let import = macro_use_import(self, span);
1128 self.r.potentially_unused_imports.push(import);
1129 module.for_each_child(self, |this, ident, ns, binding| {
1131 let imported_binding = this.r.import(binding, import);
1132 this.add_macro_use_binding(ident.name, imported_binding, span, allow_shadowing);
1136 for ident in single_imports.iter().cloned() {
1137 let result = self.r.maybe_resolve_ident_in_module(
1138 ModuleOrUniformRoot::Module(module),
1143 if let Ok(binding) = result {
1144 let import = macro_use_import(self, ident.span);
1145 self.r.potentially_unused_imports.push(import);
1146 let imported_binding = self.r.import(binding, import);
1147 self.add_macro_use_binding(
1154 struct_span_err!(self.r.session, ident.span, E0469, "imported macro not found")
1159 import_all.is_some() || !single_imports.is_empty()
1162 /// Returns `true` if this attribute list contains `macro_use`.
1163 fn contains_macro_use(&mut self, attrs: &[ast::Attribute]) -> bool {
1165 if attr.has_name(sym::macro_escape) {
1166 let msg = "`#[macro_escape]` is a deprecated synonym for `#[macro_use]`";
1167 let mut err = self.r.session.struct_span_warn(attr.span, msg);
1168 if let ast::AttrStyle::Inner = attr.style {
1169 err.help("try an outer attribute: `#[macro_use]`").emit();
1173 } else if !attr.has_name(sym::macro_use) {
1177 if !attr.is_word() {
1178 self.r.session.span_err(attr.span, "arguments to `macro_use` are not allowed here");
1186 fn visit_invoc(&mut self, id: NodeId) -> LocalExpnId {
1187 let invoc_id = id.placeholder_to_expn_id();
1188 let old_parent_scope = self.r.invocation_parent_scopes.insert(invoc_id, self.parent_scope);
1189 assert!(old_parent_scope.is_none(), "invocation data is reset for an invocation");
1193 /// Visit invocation in context in which it can emit a named item (possibly `macro_rules`)
1194 /// directly into its parent scope's module.
1195 fn visit_invoc_in_module(&mut self, id: NodeId) -> MacroRulesScopeRef<'a> {
1196 let invoc_id = self.visit_invoc(id);
1197 self.parent_scope.module.unexpanded_invocations.borrow_mut().insert(invoc_id);
1198 self.r.arenas.alloc_macro_rules_scope(MacroRulesScope::Invocation(invoc_id))
1201 fn proc_macro_stub(&self, item: &ast::Item) -> Option<(MacroKind, Ident, Span)> {
1202 if self.r.session.contains_name(&item.attrs, sym::proc_macro) {
1203 return Some((MacroKind::Bang, item.ident, item.span));
1204 } else if self.r.session.contains_name(&item.attrs, sym::proc_macro_attribute) {
1205 return Some((MacroKind::Attr, item.ident, item.span));
1206 } else if let Some(attr) = self.r.session.find_by_name(&item.attrs, sym::proc_macro_derive)
1208 if let Some(nested_meta) = attr.meta_item_list().and_then(|list| list.get(0).cloned()) {
1209 if let Some(ident) = nested_meta.ident() {
1210 return Some((MacroKind::Derive, ident, ident.span));
1217 // Mark the given macro as unused unless its name starts with `_`.
1218 // Macro uses will remove items from this set, and the remaining
1219 // items will be reported as `unused_macros`.
1220 fn insert_unused_macro(
1225 rule_spans: &[(usize, Span)],
1227 if !ident.as_str().starts_with('_') {
1228 self.r.unused_macros.insert(def_id, (node_id, ident));
1229 for (rule_i, rule_span) in rule_spans.iter() {
1230 self.r.unused_macro_rules.insert((def_id, *rule_i), (ident, *rule_span));
1235 fn define_macro(&mut self, item: &ast::Item) -> MacroRulesScopeRef<'a> {
1236 let parent_scope = self.parent_scope;
1237 let expansion = parent_scope.expansion;
1238 let def_id = self.r.local_def_id(item.id);
1239 let (ext, ident, span, macro_rules, rule_spans) = match &item.kind {
1240 ItemKind::MacroDef(def) => {
1241 let (ext, rule_spans) = self.r.compile_macro(item, self.r.session.edition());
1242 let ext = Lrc::new(ext);
1243 (ext, item.ident, item.span, def.macro_rules, rule_spans)
1245 ItemKind::Fn(..) => match self.proc_macro_stub(item) {
1246 Some((macro_kind, ident, span)) => {
1247 self.r.proc_macro_stubs.insert(def_id);
1248 (self.r.dummy_ext(macro_kind), ident, span, false, Vec::new())
1250 None => return parent_scope.macro_rules,
1252 _ => unreachable!(),
1255 let res = Res::Def(DefKind::Macro(ext.macro_kind()), def_id.to_def_id());
1256 self.r.macro_map.insert(def_id.to_def_id(), MacroData { ext, macro_rules });
1257 self.r.local_macro_def_scopes.insert(def_id, parent_scope.module);
1260 let ident = ident.normalize_to_macros_2_0();
1261 self.r.macro_names.insert(ident);
1262 let is_macro_export = self.r.session.contains_name(&item.attrs, sym::macro_export);
1263 let vis = if is_macro_export {
1264 ty::Visibility::Public
1266 ty::Visibility::Restricted(CRATE_DEF_ID.to_def_id())
1268 let binding = (res, vis, span, expansion).to_name_binding(self.r.arenas);
1269 self.r.set_binding_parent_module(binding, parent_scope.module);
1270 if is_macro_export {
1271 let module = self.r.graph_root;
1272 self.r.define(module, ident, MacroNS, (res, vis, span, expansion, IsMacroExport));
1274 self.r.check_reserved_macro_name(ident, res);
1275 self.insert_unused_macro(ident, def_id, item.id, &rule_spans);
1277 self.r.visibilities.insert(def_id, vis);
1278 let scope = self.r.arenas.alloc_macro_rules_scope(MacroRulesScope::Binding(
1279 self.r.arenas.alloc_macro_rules_binding(MacroRulesBinding {
1280 parent_macro_rules_scope: parent_scope.macro_rules,
1285 self.r.macro_rules_scopes.insert(def_id, scope);
1288 let module = parent_scope.module;
1289 let vis = match item.kind {
1290 // Visibilities must not be resolved non-speculatively twice
1291 // and we already resolved this one as a `fn` item visibility.
1292 ItemKind::Fn(..) => {
1293 self.try_resolve_visibility(&item.vis, false).unwrap_or(ty::Visibility::Public)
1295 _ => self.resolve_visibility(&item.vis),
1297 if vis != ty::Visibility::Public {
1298 self.insert_unused_macro(ident, def_id, item.id, &rule_spans);
1300 self.r.define(module, ident, MacroNS, (res, vis, span, expansion));
1301 self.r.visibilities.insert(def_id, vis);
1302 self.parent_scope.macro_rules
1307 macro_rules! method {
1308 ($visit:ident: $ty:ty, $invoc:path, $walk:ident) => {
1309 fn $visit(&mut self, node: &'b $ty) {
1310 if let $invoc(..) = node.kind {
1311 self.visit_invoc(node.id);
1313 visit::$walk(self, node);
1319 impl<'a, 'b> Visitor<'b> for BuildReducedGraphVisitor<'a, 'b> {
1320 method!(visit_expr: ast::Expr, ast::ExprKind::MacCall, walk_expr);
1321 method!(visit_pat: ast::Pat, ast::PatKind::MacCall, walk_pat);
1322 method!(visit_ty: ast::Ty, ast::TyKind::MacCall, walk_ty);
1324 fn visit_item(&mut self, item: &'b Item) {
1325 let orig_module_scope = self.parent_scope.module;
1326 self.parent_scope.macro_rules = match item.kind {
1327 ItemKind::MacroDef(..) => {
1328 let macro_rules_scope = self.define_macro(item);
1329 visit::walk_item(self, item);
1332 ItemKind::MacCall(..) => {
1333 let macro_rules_scope = self.visit_invoc_in_module(item.id);
1334 visit::walk_item(self, item);
1338 let orig_macro_rules_scope = self.parent_scope.macro_rules;
1339 self.build_reduced_graph_for_item(item);
1340 visit::walk_item(self, item);
1342 ItemKind::Mod(..) if self.contains_macro_use(&item.attrs) => {
1343 self.parent_scope.macro_rules
1345 _ => orig_macro_rules_scope,
1349 self.parent_scope.module = orig_module_scope;
1352 fn visit_stmt(&mut self, stmt: &'b ast::Stmt) {
1353 if let ast::StmtKind::MacCall(..) = stmt.kind {
1354 self.parent_scope.macro_rules = self.visit_invoc_in_module(stmt.id);
1356 visit::walk_stmt(self, stmt);
1360 fn visit_foreign_item(&mut self, foreign_item: &'b ForeignItem) {
1361 if let ForeignItemKind::MacCall(_) = foreign_item.kind {
1362 self.visit_invoc_in_module(foreign_item.id);
1366 self.build_reduced_graph_for_foreign_item(foreign_item);
1367 visit::walk_foreign_item(self, foreign_item);
1370 fn visit_block(&mut self, block: &'b Block) {
1371 let orig_current_module = self.parent_scope.module;
1372 let orig_current_macro_rules_scope = self.parent_scope.macro_rules;
1373 self.build_reduced_graph_for_block(block);
1374 visit::walk_block(self, block);
1375 self.parent_scope.module = orig_current_module;
1376 self.parent_scope.macro_rules = orig_current_macro_rules_scope;
1379 fn visit_assoc_item(&mut self, item: &'b AssocItem, ctxt: AssocCtxt) {
1380 if let AssocItemKind::MacCall(_) = item.kind {
1382 AssocCtxt::Trait => {
1383 self.visit_invoc_in_module(item.id);
1385 AssocCtxt::Impl => {
1386 self.visit_invoc(item.id);
1392 let vis = self.resolve_visibility(&item.vis);
1393 let local_def_id = self.r.local_def_id(item.id);
1394 let def_id = local_def_id.to_def_id();
1396 if !(ctxt == AssocCtxt::Impl
1397 && matches!(item.vis.kind, ast::VisibilityKind::Inherited)
1401 .contains(&ty::DefIdTree::local_parent(&*self.r, local_def_id)))
1403 // Trait impl item visibility is inherited from its trait when not specified
1404 // explicitly. In that case we cannot determine it here in early resolve,
1405 // so we leave a hole in the visibility table to be filled later.
1406 self.r.visibilities.insert(local_def_id, vis);
1409 if ctxt == AssocCtxt::Trait {
1410 let (def_kind, ns) = match item.kind {
1411 AssocItemKind::Const(..) => (DefKind::AssocConst, ValueNS),
1412 AssocItemKind::Fn(box Fn { ref sig, .. }) => {
1413 if sig.decl.has_self() {
1414 self.r.has_self.insert(def_id);
1416 (DefKind::AssocFn, ValueNS)
1418 AssocItemKind::TyAlias(..) => (DefKind::AssocTy, TypeNS),
1419 AssocItemKind::MacCall(_) => bug!(), // handled above
1422 let parent = self.parent_scope.module;
1423 let expansion = self.parent_scope.expansion;
1424 let res = Res::Def(def_kind, def_id);
1425 self.r.define(parent, item.ident, ns, (res, vis, item.span, expansion));
1428 visit::walk_assoc_item(self, item, ctxt);
1431 fn visit_attribute(&mut self, attr: &'b ast::Attribute) {
1432 if !attr.is_doc_comment() && attr::is_builtin_attr(attr) {
1435 .push((attr.get_normal_item().path.segments[0].ident, self.parent_scope));
1437 visit::walk_attribute(self, attr);
1440 fn visit_arm(&mut self, arm: &'b ast::Arm) {
1441 if arm.is_placeholder {
1442 self.visit_invoc(arm.id);
1444 visit::walk_arm(self, arm);
1448 fn visit_expr_field(&mut self, f: &'b ast::ExprField) {
1449 if f.is_placeholder {
1450 self.visit_invoc(f.id);
1452 visit::walk_expr_field(self, f);
1456 fn visit_pat_field(&mut self, fp: &'b ast::PatField) {
1457 if fp.is_placeholder {
1458 self.visit_invoc(fp.id);
1460 visit::walk_pat_field(self, fp);
1464 fn visit_generic_param(&mut self, param: &'b ast::GenericParam) {
1465 if param.is_placeholder {
1466 self.visit_invoc(param.id);
1468 visit::walk_generic_param(self, param);
1472 fn visit_param(&mut self, p: &'b ast::Param) {
1473 if p.is_placeholder {
1474 self.visit_invoc(p.id);
1476 visit::walk_param(self, p);
1480 fn visit_field_def(&mut self, sf: &'b ast::FieldDef) {
1481 if sf.is_placeholder {
1482 self.visit_invoc(sf.id);
1484 let vis = self.resolve_visibility(&sf.vis);
1485 self.r.visibilities.insert(self.r.local_def_id(sf.id), vis);
1486 visit::walk_field_def(self, sf);
1490 // Constructs the reduced graph for one variant. Variants exist in the
1491 // type and value namespaces.
1492 fn visit_variant(&mut self, variant: &'b ast::Variant) {
1493 if variant.is_placeholder {
1494 self.visit_invoc_in_module(variant.id);
1498 let parent = self.parent_scope.module;
1499 let expn_id = self.parent_scope.expansion;
1500 let ident = variant.ident;
1502 // Define a name in the type namespace.
1503 let def_id = self.r.local_def_id(variant.id);
1504 let res = Res::Def(DefKind::Variant, def_id.to_def_id());
1505 let vis = self.resolve_visibility(&variant.vis);
1506 self.r.define(parent, ident, TypeNS, (res, vis, variant.span, expn_id));
1507 self.r.visibilities.insert(def_id, vis);
1509 // If the variant is marked as non_exhaustive then lower the visibility to within the crate.
1510 let ctor_vis = if vis == ty::Visibility::Public
1511 && self.r.session.contains_name(&variant.attrs, sym::non_exhaustive)
1513 ty::Visibility::Restricted(CRATE_DEF_ID.to_def_id())
1518 // Define a constructor name in the value namespace.
1519 // Braced variants, unlike structs, generate unusable names in
1520 // value namespace, they are reserved for possible future use.
1521 // It's ok to use the variant's id as a ctor id since an
1522 // error will be reported on any use of such resolution anyway.
1523 let ctor_node_id = variant.data.ctor_id().unwrap_or(variant.id);
1524 let ctor_def_id = self.r.local_def_id(ctor_node_id);
1525 let ctor_kind = CtorKind::from_ast(&variant.data);
1526 let ctor_res = Res::Def(DefKind::Ctor(CtorOf::Variant, ctor_kind), ctor_def_id.to_def_id());
1527 self.r.define(parent, ident, ValueNS, (ctor_res, ctor_vis, variant.span, expn_id));
1528 if ctor_def_id != def_id {
1529 self.r.visibilities.insert(ctor_def_id, ctor_vis);
1531 // Record field names for error reporting.
1532 self.insert_field_names_local(ctor_def_id.to_def_id(), &variant.data);
1534 visit::walk_variant(self, variant);
1537 fn visit_crate(&mut self, krate: &'b ast::Crate) {
1538 if krate.is_placeholder {
1539 self.visit_invoc_in_module(krate.id);
1541 visit::walk_crate(self, krate);
1542 self.contains_macro_use(&krate.attrs);