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, Id: Into<DefId>> ToNameBinding<'a>
43 for (Module<'a>, ty::Visibility<Id>, Span, LocalExpnId)
45 fn to_name_binding(self, arenas: &'a ResolverArenas<'a>) -> &'a NameBinding<'a> {
46 arenas.alloc_name_binding(NameBinding {
47 kind: NameBindingKind::Module(self.0),
49 vis: self.1.to_def_id(),
56 impl<'a, Id: Into<DefId>> ToNameBinding<'a> for (Res, ty::Visibility<Id>, Span, LocalExpnId) {
57 fn to_name_binding(self, arenas: &'a ResolverArenas<'a>) -> &'a NameBinding<'a> {
58 arenas.alloc_name_binding(NameBinding {
59 kind: NameBindingKind::Res(self.0, false),
61 vis: self.1.to_def_id(),
70 impl<'a> ToNameBinding<'a> for (Res, ty::Visibility, Span, LocalExpnId, IsMacroExport) {
71 fn to_name_binding(self, arenas: &'a ResolverArenas<'a>) -> &'a NameBinding<'a> {
72 arenas.alloc_name_binding(NameBinding {
73 kind: NameBindingKind::Res(self.0, true),
75 vis: self.1.to_def_id(),
82 impl<'a> Resolver<'a> {
83 /// Defines `name` in namespace `ns` of module `parent` to be `def` if it is not yet defined;
84 /// otherwise, reports an error.
85 pub(crate) fn define<T>(&mut self, parent: Module<'a>, ident: Ident, ns: Namespace, def: T)
89 let binding = def.to_name_binding(self.arenas);
90 let key = self.new_key(ident, ns);
91 if let Err(old_binding) = self.try_define(parent, key, binding) {
92 self.report_conflict(parent, ident, ns, old_binding, &binding);
96 /// Walks up the tree of definitions starting at `def_id`,
97 /// stopping at the first encountered module.
98 /// Parent block modules for arbitrary def-ids are not recorded for the local crate,
99 /// and are not preserved in metadata for foreign crates, so block modules are never
100 /// returned by this function.
102 /// For the local crate ignoring block modules may be incorrect, so use this method with care.
104 /// For foreign crates block modules can be ignored without introducing observable differences,
105 /// moreover they has to be ignored right now because they are not kept in metadata.
106 /// Foreign parent modules are used for resolving names used by foreign macros with def-site
107 /// hygiene, therefore block module ignorability relies on macros with def-site hygiene and
108 /// block module parents being unreachable from other crates.
109 /// Reachable macros with block module parents exist due to `#[macro_export] macro_rules!`,
110 /// but they cannot use def-site hygiene, so the assumption holds
111 /// (<https://github.com/rust-lang/rust/pull/77984#issuecomment-712445508>).
112 pub fn get_nearest_non_block_module(&mut self, mut def_id: DefId) -> Module<'a> {
114 match self.get_module(def_id) {
115 Some(module) => return module,
116 None => def_id = self.parent(def_id),
121 pub fn expect_module(&mut self, def_id: DefId) -> Module<'a> {
122 self.get_module(def_id).expect("argument `DefId` is not a module")
125 /// If `def_id` refers to a module (in resolver's sense, i.e. a module item, crate root, enum,
126 /// or trait), then this function returns that module's resolver representation, otherwise it
128 pub(crate) fn get_module(&mut self, def_id: DefId) -> Option<Module<'a>> {
129 if let module @ Some(..) = self.module_map.get(&def_id) {
130 return module.copied();
133 if !def_id.is_local() {
134 let def_kind = self.cstore().def_kind(def_id);
136 DefKind::Mod | DefKind::Enum | DefKind::Trait => {
137 let def_key = self.cstore().def_key(def_id);
138 let parent = def_key.parent.map(|index| {
139 self.get_nearest_non_block_module(DefId { index, krate: def_id.krate })
141 let name = if let Some(cnum) = def_id.as_crate_root() {
142 self.cstore().crate_name(cnum)
144 def_key.disambiguated_data.data.get_opt_name().expect("module without name")
147 Some(self.new_module(
149 ModuleKind::Def(def_kind, def_id, name),
150 self.cstore().module_expansion_untracked(def_id, &self.session),
151 self.cstore().get_span_untracked(def_id, &self.session),
152 // FIXME: Account for `#[no_implicit_prelude]` attributes.
153 parent.map_or(false, |module| module.no_implicit_prelude),
163 pub(crate) fn expn_def_scope(&mut self, expn_id: ExpnId) -> Module<'a> {
164 match expn_id.expn_data().macro_def_id {
165 Some(def_id) => self.macro_def_scope(def_id),
168 .and_then(|expn_id| self.ast_transform_scopes.get(&expn_id))
169 .unwrap_or(&self.graph_root),
173 pub(crate) fn macro_def_scope(&mut self, def_id: DefId) -> Module<'a> {
174 if let Some(id) = def_id.as_local() {
175 self.local_macro_def_scopes[&id]
177 self.get_nearest_non_block_module(def_id)
181 pub(crate) fn get_macro(&mut self, res: Res) -> Option<MacroData> {
183 Res::Def(DefKind::Macro(..), def_id) => Some(self.get_macro_by_def_id(def_id)),
184 Res::NonMacroAttr(_) => {
185 Some(MacroData { ext: self.non_macro_attr.clone(), macro_rules: false })
191 pub(crate) fn get_macro_by_def_id(&mut self, def_id: DefId) -> MacroData {
192 if let Some(macro_data) = self.macro_map.get(&def_id) {
193 return macro_data.clone();
196 let (ext, macro_rules) = match self.cstore().load_macro_untracked(def_id, &self.session) {
197 LoadedMacro::MacroDef(item, edition) => (
198 Lrc::new(self.compile_macro(&item, edition).0),
199 matches!(item.kind, ItemKind::MacroDef(def) if def.macro_rules),
201 LoadedMacro::ProcMacro(extz) => (Lrc::new(extz), false),
204 let macro_data = MacroData { ext, macro_rules };
205 self.macro_map.insert(def_id, macro_data.clone());
209 pub(crate) fn build_reduced_graph(
211 fragment: &AstFragment,
212 parent_scope: ParentScope<'a>,
213 ) -> MacroRulesScopeRef<'a> {
214 collect_definitions(self, fragment, parent_scope.expansion);
215 let mut visitor = BuildReducedGraphVisitor { r: self, parent_scope };
216 fragment.visit_with(&mut visitor);
217 visitor.parent_scope.macro_rules
220 pub(crate) fn build_reduced_graph_external(&mut self, module: Module<'a>) {
221 for child in self.cstore().module_children_untracked(module.def_id(), self.session) {
222 let parent_scope = ParentScope::module(module, self);
223 BuildReducedGraphVisitor { r: self, parent_scope }
224 .build_reduced_graph_for_external_crate_res(child);
229 struct BuildReducedGraphVisitor<'a, 'b> {
230 r: &'b mut Resolver<'a>,
231 parent_scope: ParentScope<'a>,
234 impl<'a> AsMut<Resolver<'a>> for BuildReducedGraphVisitor<'a, '_> {
235 fn as_mut(&mut self) -> &mut Resolver<'a> {
240 impl<'a, 'b> BuildReducedGraphVisitor<'a, 'b> {
241 fn resolve_visibility(&mut self, vis: &ast::Visibility) -> ty::Visibility {
242 self.try_resolve_visibility(vis, true).unwrap_or_else(|err| {
243 self.r.report_vis_error(err);
244 ty::Visibility::Public
248 fn try_resolve_visibility<'ast>(
250 vis: &'ast ast::Visibility,
252 ) -> Result<ty::Visibility, VisResolutionError<'ast>> {
253 let parent_scope = &self.parent_scope;
255 ast::VisibilityKind::Public => Ok(ty::Visibility::Public),
256 ast::VisibilityKind::Inherited => {
257 Ok(match self.parent_scope.module.kind {
258 // Any inherited visibility resolved directly inside an enum or trait
259 // (i.e. variants, fields, and trait items) inherits from the visibility
260 // of the enum or trait.
261 ModuleKind::Def(DefKind::Enum | DefKind::Trait, def_id, _) => {
262 self.r.visibilities[&def_id.expect_local()]
264 // Otherwise, the visibility is restricted to the nearest parent `mod` item.
265 _ => ty::Visibility::Restricted(
266 self.parent_scope.module.nearest_parent_mod().expect_local(),
270 ast::VisibilityKind::Restricted { ref path, id, .. } => {
271 // Make `PRIVATE_IN_PUBLIC` lint a hard error.
272 self.r.has_pub_restricted = true;
273 // For visibilities we are not ready to provide correct implementation of "uniform
274 // paths" right now, so on 2018 edition we only allow module-relative paths for now.
275 // On 2015 edition visibilities are resolved as crate-relative by default,
276 // so we are prepending a root segment if necessary.
277 let ident = path.segments.get(0).expect("empty path in visibility").ident;
278 let crate_root = if ident.is_path_segment_keyword() {
280 } else if ident.span.rust_2015() {
281 Some(Segment::from_ident(Ident::new(
283 path.span.shrink_to_lo().with_ctxt(ident.span.ctxt()),
286 return Err(VisResolutionError::Relative2018(ident.span, path));
289 let segments = crate_root
291 .chain(path.segments.iter().map(|seg| seg.into()))
292 .collect::<Vec<_>>();
293 let expected_found_error = |res| {
294 Err(VisResolutionError::ExpectedFound(
296 Segment::names_to_string(&segments),
300 match self.r.resolve_path(
304 finalize.then(|| Finalize::new(id, path.span)),
307 PathResult::Module(ModuleOrUniformRoot::Module(module)) => {
308 let res = module.res().expect("visibility resolved to unnamed block");
310 self.r.record_partial_res(id, PartialRes::new(res));
312 if module.is_normal() {
314 Ok(ty::Visibility::Public)
316 let vis = ty::Visibility::Restricted(res.def_id());
317 if self.r.is_accessible_from(vis, parent_scope.module) {
318 Ok(vis.expect_local())
320 Err(VisResolutionError::AncestorOnly(path.span))
324 expected_found_error(res)
327 PathResult::Module(..) => Err(VisResolutionError::ModuleOnly(path.span)),
328 PathResult::NonModule(partial_res) => {
329 expected_found_error(partial_res.base_res())
331 PathResult::Failed { span, label, suggestion, .. } => {
332 Err(VisResolutionError::FailedToResolve(span, label, suggestion))
334 PathResult::Indeterminate => Err(VisResolutionError::Indeterminate(path.span)),
340 fn insert_field_names_local(&mut self, def_id: DefId, vdata: &ast::VariantData) {
341 let field_names = vdata
344 .map(|field| respan(field.span, field.ident.map_or(kw::Empty, |ident| ident.name)))
346 self.insert_field_names(def_id, field_names);
349 fn insert_field_names(&mut self, def_id: DefId, field_names: Vec<Spanned<Symbol>>) {
350 self.r.field_names.insert(def_id, field_names);
353 fn block_needs_anonymous_module(&mut self, block: &Block) -> bool {
354 // If any statements are items, we need to create an anonymous module
358 .any(|statement| matches!(statement.kind, StmtKind::Item(_) | StmtKind::MacCall(_)))
361 // Add an import to the current module.
364 module_path: Vec<Segment>,
365 kind: ImportKind<'a>,
373 let current_module = self.parent_scope.module;
374 let import = self.r.arenas.alloc_import(Import {
376 parent_scope: self.parent_scope,
378 imported_module: Cell::new(None),
382 use_span_with_attributes: item.span_with_attributes(),
383 has_attributes: !item.attrs.is_empty(),
386 vis: Cell::new(Some(vis)),
387 used: Cell::new(false),
390 self.r.indeterminate_imports.push(import);
392 // Don't add unresolved underscore imports to modules
393 ImportKind::Single { target: Ident { name: kw::Underscore, .. }, .. } => {}
394 ImportKind::Single { target, type_ns_only, .. } => {
395 self.r.per_ns(|this, ns| {
396 if !type_ns_only || ns == TypeNS {
397 let key = this.new_key(target, ns);
398 let mut resolution = this.resolution(current_module, key).borrow_mut();
399 resolution.add_single_import(import);
403 // We don't add prelude imports to the globs since they only affect lexical scopes,
404 // which are not relevant to import resolution.
405 ImportKind::Glob { is_prelude: true, .. } => {}
406 ImportKind::Glob { .. } => current_module.globs.borrow_mut().push(import),
411 fn build_reduced_graph_for_use_tree(
413 // This particular use tree
414 use_tree: &ast::UseTree,
416 parent_prefix: &[Segment],
418 // The whole `use` item
424 "build_reduced_graph_for_use_tree(parent_prefix={:?}, use_tree={:?}, nested={})",
425 parent_prefix, use_tree, nested
428 let mut prefix_iter = parent_prefix
431 .chain(use_tree.prefix.segments.iter().map(|seg| seg.into()))
434 // On 2015 edition imports are resolved as crate-relative by default,
435 // so prefixes are prepended with crate root segment if necessary.
436 // The root is prepended lazily, when the first non-empty prefix or terminating glob
437 // appears, so imports in braced groups can have roots prepended independently.
438 let is_glob = matches!(use_tree.kind, ast::UseTreeKind::Glob);
439 let crate_root = match prefix_iter.peek() {
440 Some(seg) if !seg.ident.is_path_segment_keyword() && seg.ident.span.rust_2015() => {
441 Some(seg.ident.span.ctxt())
443 None if is_glob && use_tree.span.rust_2015() => Some(use_tree.span.ctxt()),
447 Segment::from_ident(Ident::new(
449 use_tree.prefix.span.shrink_to_lo().with_ctxt(ctxt),
453 let prefix = crate_root.into_iter().chain(prefix_iter).collect::<Vec<_>>();
454 debug!("build_reduced_graph_for_use_tree: prefix={:?}", prefix);
456 let empty_for_self = |prefix: &[Segment]| {
457 prefix.is_empty() || prefix.len() == 1 && prefix[0].ident.name == kw::PathRoot
459 match use_tree.kind {
460 ast::UseTreeKind::Simple(rename, id1, id2) => {
461 let mut ident = use_tree.ident();
462 let mut module_path = prefix;
463 let mut source = module_path.pop().unwrap();
464 let mut type_ns_only = false;
466 self.r.visibilities.insert(self.r.local_def_id(id), vis);
467 if id1 != ast::DUMMY_NODE_ID {
468 self.r.visibilities.insert(self.r.local_def_id(id1), vis);
470 if id2 != ast::DUMMY_NODE_ID {
471 self.r.visibilities.insert(self.r.local_def_id(id2), vis);
475 // Correctly handle `self`
476 if source.ident.name == kw::SelfLower {
479 if empty_for_self(&module_path) {
482 ResolutionError::SelfImportOnlyInImportListWithNonEmptyPrefix,
487 // Replace `use foo::{ self };` with `use foo;`
488 source = module_path.pop().unwrap();
489 if rename.is_none() {
490 ident = source.ident;
495 if source.ident.name == kw::SelfLower {
496 let parent = module_path.last();
498 let span = match parent {
499 // only `::self` from `use foo::self as bar`
500 Some(seg) => seg.ident.span.shrink_to_hi().to(source.ident.span),
501 None => source.ident.span,
503 let span_with_rename = match rename {
504 // only `self as bar` from `use foo::self as bar`
505 Some(rename) => source.ident.span.to(rename.span),
506 None => source.ident.span,
510 ResolutionError::SelfImportsOnlyAllowedWithin {
511 root: parent.is_none(),
516 // Error recovery: replace `use foo::self;` with `use foo;`
517 if let Some(parent) = module_path.pop() {
519 if rename.is_none() {
520 ident = source.ident;
525 // Disallow `use $crate;`
526 if source.ident.name == kw::DollarCrate && module_path.is_empty() {
527 let crate_root = self.r.resolve_crate_root(source.ident);
528 let crate_name = match crate_root.kind {
529 ModuleKind::Def(.., name) => name,
530 ModuleKind::Block => unreachable!(),
532 // HACK(eddyb) unclear how good this is, but keeping `$crate`
533 // in `source` breaks `src/test/ui/imports/import-crate-var.rs`,
534 // while the current crate doesn't have a valid `crate_name`.
535 if crate_name != kw::Empty {
536 // `crate_name` should not be interpreted as relative.
537 module_path.push(Segment::from_ident_and_id(
538 Ident { name: kw::PathRoot, span: source.ident.span },
539 self.r.next_node_id(),
541 source.ident.name = crate_name;
543 if rename.is_none() {
544 ident.name = crate_name;
549 .struct_span_err(item.span, "`$crate` may not be imported")
554 if ident.name == kw::Crate {
555 self.r.session.span_err(
557 "crate root imports need to be explicitly named: \
558 `use crate as name;`",
562 let kind = ImportKind::Single {
563 source: source.ident,
565 source_bindings: PerNS {
566 type_ns: Cell::new(Err(Determinacy::Undetermined)),
567 value_ns: Cell::new(Err(Determinacy::Undetermined)),
568 macro_ns: Cell::new(Err(Determinacy::Undetermined)),
570 target_bindings: PerNS {
571 type_ns: Cell::new(None),
572 value_ns: Cell::new(None),
573 macro_ns: Cell::new(None),
577 additional_ids: (id1, id2),
591 ast::UseTreeKind::Glob => {
592 let kind = ImportKind::Glob {
593 is_prelude: self.r.session.contains_name(&item.attrs, sym::prelude_import),
594 max_vis: Cell::new(None),
596 self.r.visibilities.insert(self.r.local_def_id(id), vis);
597 self.add_import(prefix, kind, use_tree.span, id, item, root_span, item.id, vis);
599 ast::UseTreeKind::Nested(ref items) => {
600 // Ensure there is at most one `self` in the list
601 let self_spans = items
603 .filter_map(|&(ref use_tree, _)| {
604 if let ast::UseTreeKind::Simple(..) = use_tree.kind {
605 if use_tree.ident().name == kw::SelfLower {
606 return Some(use_tree.span);
612 .collect::<Vec<_>>();
613 if self_spans.len() > 1 {
614 let mut e = self.r.into_struct_error(
616 ResolutionError::SelfImportCanOnlyAppearOnceInTheList,
619 for other_span in self_spans.iter().skip(1) {
620 e.span_label(*other_span, "another `self` import appears here");
626 for &(ref tree, id) in items {
627 self.build_reduced_graph_for_use_tree(
628 // This particular use tree
629 tree, id, &prefix, true, // The whole `use` item
630 item, vis, root_span,
634 // Empty groups `a::b::{}` are turned into synthetic `self` imports
635 // `a::b::c::{self as _}`, so that their prefixes are correctly
636 // resolved and checked for privacy/stability/etc.
637 if items.is_empty() && !empty_for_self(&prefix) {
638 let new_span = prefix[prefix.len() - 1].ident.span;
639 let tree = ast::UseTree {
640 prefix: ast::Path::from_ident(Ident::new(kw::SelfLower, new_span)),
641 kind: ast::UseTreeKind::Simple(
642 Some(Ident::new(kw::Underscore, new_span)),
648 self.build_reduced_graph_for_use_tree(
649 // This particular use tree
654 // The whole `use` item
656 ty::Visibility::Restricted(
657 self.parent_scope.module.nearest_parent_mod().expect_local(),
666 /// Constructs the reduced graph for one item.
667 fn build_reduced_graph_for_item(&mut self, item: &'b Item) {
668 let parent_scope = &self.parent_scope;
669 let parent = parent_scope.module;
670 let expansion = parent_scope.expansion;
671 let ident = item.ident;
673 let vis = self.resolve_visibility(&item.vis);
674 let local_def_id = self.r.local_def_id(item.id);
675 let def_id = local_def_id.to_def_id();
677 self.r.visibilities.insert(local_def_id, vis);
680 ItemKind::Use(ref use_tree) => {
681 self.build_reduced_graph_for_use_tree(
682 // This particular use tree
687 // The whole `use` item
694 ItemKind::ExternCrate(orig_name) => {
695 self.build_reduced_graph_for_extern_crate(
704 ItemKind::Mod(..) => {
705 let module = self.r.new_module(
707 ModuleKind::Def(DefKind::Mod, def_id, ident.name),
708 expansion.to_expn_id(),
710 parent.no_implicit_prelude
711 || self.r.session.contains_name(&item.attrs, sym::no_implicit_prelude),
713 self.r.define(parent, ident, TypeNS, (module, vis, sp, expansion));
715 // Descend into the module.
716 self.parent_scope.module = module;
719 // These items live in the value namespace.
720 ItemKind::Static(_, mt, _) => {
721 let res = Res::Def(DefKind::Static(mt), def_id);
722 self.r.define(parent, ident, ValueNS, (res, vis, sp, expansion));
724 ItemKind::Const(..) => {
725 let res = Res::Def(DefKind::Const, def_id);
726 self.r.define(parent, ident, ValueNS, (res, vis, sp, expansion));
728 ItemKind::Fn(..) => {
729 let res = Res::Def(DefKind::Fn, def_id);
730 self.r.define(parent, ident, ValueNS, (res, vis, sp, expansion));
732 // Functions introducing procedural macros reserve a slot
733 // in the macro namespace as well (see #52225).
734 self.define_macro(item);
737 // These items live in the type namespace.
738 ItemKind::TyAlias(..) => {
739 let res = Res::Def(DefKind::TyAlias, def_id);
740 self.r.define(parent, ident, TypeNS, (res, vis, sp, expansion));
743 ItemKind::Enum(_, _) => {
744 let module = self.r.new_module(
746 ModuleKind::Def(DefKind::Enum, def_id, ident.name),
747 expansion.to_expn_id(),
749 parent.no_implicit_prelude,
751 self.r.define(parent, ident, TypeNS, (module, vis, sp, expansion));
752 self.parent_scope.module = module;
755 ItemKind::TraitAlias(..) => {
756 let res = Res::Def(DefKind::TraitAlias, def_id);
757 self.r.define(parent, ident, TypeNS, (res, vis, sp, expansion));
760 // These items live in both the type and value namespaces.
761 ItemKind::Struct(ref vdata, _) => {
762 // Define a name in the type namespace.
763 let res = Res::Def(DefKind::Struct, def_id);
764 self.r.define(parent, ident, TypeNS, (res, vis, sp, expansion));
766 // Record field names for error reporting.
767 self.insert_field_names_local(def_id, vdata);
769 // If this is a tuple or unit struct, define a name
770 // in the value namespace as well.
771 if let Some(ctor_node_id) = vdata.ctor_id() {
772 // If the structure is marked as non_exhaustive then lower the visibility
773 // to within the crate.
774 let mut ctor_vis = if vis.is_public()
775 && self.r.session.contains_name(&item.attrs, sym::non_exhaustive)
777 ty::Visibility::Restricted(CRATE_DEF_ID)
782 let mut ret_fields = Vec::with_capacity(vdata.fields().len());
784 for field in vdata.fields() {
785 // NOTE: The field may be an expansion placeholder, but expansion sets
786 // correct visibilities for unnamed field placeholders specifically, so the
787 // constructor visibility should still be determined correctly.
789 .try_resolve_visibility(&field.vis, false)
790 .unwrap_or(ty::Visibility::Public);
791 if ctor_vis.is_at_least(field_vis, &*self.r) {
792 ctor_vis = field_vis;
794 ret_fields.push(field_vis.to_def_id());
796 let ctor_def_id = self.r.local_def_id(ctor_node_id);
797 let ctor_res = Res::Def(
798 DefKind::Ctor(CtorOf::Struct, CtorKind::from_ast(vdata)),
799 ctor_def_id.to_def_id(),
801 self.r.define(parent, ident, ValueNS, (ctor_res, ctor_vis, sp, expansion));
802 self.r.visibilities.insert(ctor_def_id, ctor_vis);
806 .insert(def_id, (ctor_res, ctor_vis.to_def_id(), ret_fields));
810 ItemKind::Union(ref vdata, _) => {
811 let res = Res::Def(DefKind::Union, def_id);
812 self.r.define(parent, ident, TypeNS, (res, vis, sp, expansion));
814 // Record field names for error reporting.
815 self.insert_field_names_local(def_id, vdata);
818 ItemKind::Trait(..) => {
819 // Add all the items within to a new module.
820 let module = self.r.new_module(
822 ModuleKind::Def(DefKind::Trait, def_id, ident.name),
823 expansion.to_expn_id(),
825 parent.no_implicit_prelude,
827 self.r.define(parent, ident, TypeNS, (module, vis, sp, expansion));
828 self.parent_scope.module = module;
831 // These items do not add names to modules.
832 ItemKind::Impl(box Impl { of_trait: Some(..), .. }) => {
833 self.r.trait_impl_items.insert(local_def_id);
835 ItemKind::Impl { .. } | ItemKind::ForeignMod(..) | ItemKind::GlobalAsm(..) => {}
837 ItemKind::MacroDef(..) | ItemKind::MacCall(_) => unreachable!(),
841 fn build_reduced_graph_for_extern_crate(
843 orig_name: Option<Symbol>,
845 local_def_id: LocalDefId,
849 let ident = item.ident;
851 let parent_scope = self.parent_scope;
852 let expansion = parent_scope.expansion;
854 let (used, module, binding) = if orig_name.is_none() && ident.name == kw::SelfLower {
857 .struct_span_err(item.span, "`extern crate self;` requires renaming")
860 "rename the `self` crate to be able to import it",
861 "extern crate self as name;",
862 Applicability::HasPlaceholders,
866 } else if orig_name == Some(kw::SelfLower) {
867 Some(self.r.graph_root)
869 self.r.crate_loader.process_extern_crate(item, &self.r.definitions, local_def_id).map(
871 self.r.extern_crate_map.insert(local_def_id, crate_id);
872 self.r.expect_module(crate_id.as_def_id())
877 let used = self.process_macro_use_imports(item, module);
878 let vis = ty::Visibility::<LocalDefId>::Public;
879 let binding = (module, vis, sp, expansion).to_name_binding(self.r.arenas);
880 (used, Some(ModuleOrUniformRoot::Module(module)), binding)
882 .unwrap_or((true, None, self.r.dummy_binding));
883 let import = self.r.arenas.alloc_import(Import {
884 kind: ImportKind::ExternCrate { source: orig_name, target: ident },
887 parent_scope: self.parent_scope,
888 imported_module: Cell::new(module),
889 has_attributes: !item.attrs.is_empty(),
890 use_span_with_attributes: item.span_with_attributes(),
892 root_span: item.span,
894 module_path: Vec::new(),
895 vis: Cell::new(Some(vis)),
896 used: Cell::new(used),
898 self.r.potentially_unused_imports.push(import);
899 let imported_binding = self.r.import(binding, import);
900 if ptr::eq(parent, self.r.graph_root) {
901 if let Some(entry) = self.r.extern_prelude.get(&ident.normalize_to_macros_2_0()) {
902 if expansion != LocalExpnId::ROOT
903 && orig_name.is_some()
904 && entry.extern_crate_item.is_none()
906 let msg = "macro-expanded `extern crate` items cannot \
907 shadow names passed with `--extern`";
908 self.r.session.span_err(item.span, msg);
911 let entry = self.r.extern_prelude.entry(ident.normalize_to_macros_2_0()).or_insert(
912 ExternPreludeEntry { extern_crate_item: None, introduced_by_item: true },
914 entry.extern_crate_item = Some(imported_binding);
915 if orig_name.is_some() {
916 entry.introduced_by_item = true;
919 self.r.define(parent, ident, TypeNS, imported_binding);
922 /// Constructs the reduced graph for one foreign item.
923 fn build_reduced_graph_for_foreign_item(&mut self, item: &ForeignItem) {
924 let local_def_id = self.r.local_def_id(item.id);
925 let def_id = local_def_id.to_def_id();
926 let (def_kind, ns) = match item.kind {
927 ForeignItemKind::Fn(..) => (DefKind::Fn, ValueNS),
928 ForeignItemKind::Static(_, mt, _) => (DefKind::Static(mt), ValueNS),
929 ForeignItemKind::TyAlias(..) => (DefKind::ForeignTy, TypeNS),
930 ForeignItemKind::MacCall(_) => unreachable!(),
932 let parent = self.parent_scope.module;
933 let expansion = self.parent_scope.expansion;
934 let vis = self.resolve_visibility(&item.vis);
935 let res = Res::Def(def_kind, def_id);
936 self.r.define(parent, item.ident, ns, (res, vis, item.span, expansion));
937 self.r.visibilities.insert(local_def_id, vis);
940 fn build_reduced_graph_for_block(&mut self, block: &Block) {
941 let parent = self.parent_scope.module;
942 let expansion = self.parent_scope.expansion;
943 if self.block_needs_anonymous_module(block) {
944 let module = self.r.new_module(
947 expansion.to_expn_id(),
949 parent.no_implicit_prelude,
951 self.r.block_map.insert(block.id, module);
952 self.parent_scope.module = module; // Descend into the block.
956 /// Builds the reduced graph for a single item in an external crate.
957 fn build_reduced_graph_for_external_crate_res(&mut self, child: ModChild) {
958 let parent = self.parent_scope.module;
959 let ModChild { ident, res, vis, span, macro_rules } = child;
960 let res = res.expect_non_local();
961 let expansion = self.parent_scope.expansion;
962 // Record primary definitions.
964 Res::Def(DefKind::Mod | DefKind::Enum | DefKind::Trait, def_id) => {
965 let module = self.r.expect_module(def_id);
966 self.r.define(parent, ident, TypeNS, (module, vis, span, expansion));
975 | DefKind::TraitAlias
980 | Res::ToolMod => self.r.define(parent, ident, TypeNS, (res, vis, span, expansion)),
986 | DefKind::AssocConst
989 ) => self.r.define(parent, ident, ValueNS, (res, vis, span, expansion)),
990 Res::Def(DefKind::Macro(..), _) | Res::NonMacroAttr(..) => {
992 self.r.define(parent, ident, MacroNS, (res, vis, span, expansion))
997 | DefKind::ConstParam
998 | DefKind::ExternCrate
1000 | DefKind::ForeignMod
1001 | DefKind::AnonConst
1002 | DefKind::InlineConst
1004 | DefKind::LifetimeParam
1005 | DefKind::GlobalAsm
1008 | DefKind::Generator,
1012 | Res::SelfTy { .. }
1014 | Res::Err => bug!("unexpected resolution: {:?}", res),
1016 // Record some extra data for better diagnostics.
1017 let cstore = self.r.cstore();
1019 Res::Def(DefKind::Struct, def_id) => {
1021 cstore.struct_field_names_untracked(def_id, self.r.session).collect();
1022 let ctor = cstore.ctor_def_id_and_kind_untracked(def_id);
1023 if let Some((ctor_def_id, ctor_kind)) = ctor {
1024 let ctor_res = Res::Def(DefKind::Ctor(CtorOf::Struct, ctor_kind), ctor_def_id);
1025 let ctor_vis = cstore.visibility_untracked(ctor_def_id);
1026 let field_visibilities =
1027 cstore.struct_field_visibilities_untracked(def_id).collect();
1029 .struct_constructors
1030 .insert(def_id, (ctor_res, ctor_vis, field_visibilities));
1032 self.insert_field_names(def_id, field_names);
1034 Res::Def(DefKind::Union, def_id) => {
1036 cstore.struct_field_names_untracked(def_id, self.r.session).collect();
1037 self.insert_field_names(def_id, field_names);
1039 Res::Def(DefKind::AssocFn, def_id) => {
1040 if cstore.fn_has_self_parameter_untracked(def_id, self.r.session) {
1041 self.r.has_self.insert(def_id);
1048 fn add_macro_use_binding(
1051 binding: &'a NameBinding<'a>,
1053 allow_shadowing: bool,
1055 if self.r.macro_use_prelude.insert(name, binding).is_some() && !allow_shadowing {
1056 let msg = format!("`{}` is already in scope", name);
1058 "macro-expanded `#[macro_use]`s may not shadow existing macros (see RFC 1560)";
1059 self.r.session.struct_span_err(span, &msg).note(note).emit();
1063 /// Returns `true` if we should consider the underlying `extern crate` to be used.
1064 fn process_macro_use_imports(&mut self, item: &Item, module: Module<'a>) -> bool {
1065 let mut import_all = None;
1066 let mut single_imports = Vec::new();
1067 for attr in &item.attrs {
1068 if attr.has_name(sym::macro_use) {
1069 if self.parent_scope.module.parent.is_some() {
1074 "an `extern crate` loading macros must be at the crate root"
1078 if let ItemKind::ExternCrate(Some(orig_name)) = item.kind {
1079 if orig_name == kw::SelfLower {
1084 "`#[macro_use]` is not supported on `extern crate self`",
1089 let ill_formed = |span| {
1090 struct_span_err!(self.r.session, span, E0466, "bad macro import").emit();
1093 Some(meta) => match meta.kind {
1094 MetaItemKind::Word => {
1095 import_all = Some(meta.span);
1098 MetaItemKind::List(nested_metas) => {
1099 for nested_meta in nested_metas {
1100 match nested_meta.ident() {
1101 Some(ident) if nested_meta.is_word() => {
1102 single_imports.push(ident)
1104 _ => ill_formed(nested_meta.span()),
1108 MetaItemKind::NameValue(..) => ill_formed(meta.span),
1110 None => ill_formed(attr.span),
1115 let macro_use_import = |this: &Self, span| {
1116 this.r.arenas.alloc_import(Import {
1117 kind: ImportKind::MacroUse,
1120 parent_scope: this.parent_scope,
1121 imported_module: Cell::new(Some(ModuleOrUniformRoot::Module(module))),
1122 use_span_with_attributes: item.span_with_attributes(),
1123 has_attributes: !item.attrs.is_empty(),
1124 use_span: item.span,
1127 module_path: Vec::new(),
1128 vis: Cell::new(Some(ty::Visibility::Restricted(CRATE_DEF_ID))),
1129 used: Cell::new(false),
1133 let allow_shadowing = self.parent_scope.expansion == LocalExpnId::ROOT;
1134 if let Some(span) = import_all {
1135 let import = macro_use_import(self, span);
1136 self.r.potentially_unused_imports.push(import);
1137 module.for_each_child(self, |this, ident, ns, binding| {
1139 let imported_binding = this.r.import(binding, import);
1140 this.add_macro_use_binding(ident.name, imported_binding, span, allow_shadowing);
1144 for ident in single_imports.iter().cloned() {
1145 let result = self.r.maybe_resolve_ident_in_module(
1146 ModuleOrUniformRoot::Module(module),
1151 if let Ok(binding) = result {
1152 let import = macro_use_import(self, ident.span);
1153 self.r.potentially_unused_imports.push(import);
1154 let imported_binding = self.r.import(binding, import);
1155 self.add_macro_use_binding(
1162 struct_span_err!(self.r.session, ident.span, E0469, "imported macro not found")
1167 import_all.is_some() || !single_imports.is_empty()
1170 /// Returns `true` if this attribute list contains `macro_use`.
1171 fn contains_macro_use(&mut self, attrs: &[ast::Attribute]) -> bool {
1173 if attr.has_name(sym::macro_escape) {
1174 let msg = "`#[macro_escape]` is a deprecated synonym for `#[macro_use]`";
1175 let mut err = self.r.session.struct_span_warn(attr.span, msg);
1176 if let ast::AttrStyle::Inner = attr.style {
1177 err.help("try an outer attribute: `#[macro_use]`").emit();
1181 } else if !attr.has_name(sym::macro_use) {
1185 if !attr.is_word() {
1186 self.r.session.span_err(attr.span, "arguments to `macro_use` are not allowed here");
1194 fn visit_invoc(&mut self, id: NodeId) -> LocalExpnId {
1195 let invoc_id = id.placeholder_to_expn_id();
1196 let old_parent_scope = self.r.invocation_parent_scopes.insert(invoc_id, self.parent_scope);
1197 assert!(old_parent_scope.is_none(), "invocation data is reset for an invocation");
1201 /// Visit invocation in context in which it can emit a named item (possibly `macro_rules`)
1202 /// directly into its parent scope's module.
1203 fn visit_invoc_in_module(&mut self, id: NodeId) -> MacroRulesScopeRef<'a> {
1204 let invoc_id = self.visit_invoc(id);
1205 self.parent_scope.module.unexpanded_invocations.borrow_mut().insert(invoc_id);
1206 self.r.arenas.alloc_macro_rules_scope(MacroRulesScope::Invocation(invoc_id))
1209 fn proc_macro_stub(&self, item: &ast::Item) -> Option<(MacroKind, Ident, Span)> {
1210 if self.r.session.contains_name(&item.attrs, sym::proc_macro) {
1211 return Some((MacroKind::Bang, item.ident, item.span));
1212 } else if self.r.session.contains_name(&item.attrs, sym::proc_macro_attribute) {
1213 return Some((MacroKind::Attr, item.ident, item.span));
1214 } else if let Some(attr) = self.r.session.find_by_name(&item.attrs, sym::proc_macro_derive)
1216 if let Some(nested_meta) = attr.meta_item_list().and_then(|list| list.get(0).cloned()) {
1217 if let Some(ident) = nested_meta.ident() {
1218 return Some((MacroKind::Derive, ident, ident.span));
1225 // Mark the given macro as unused unless its name starts with `_`.
1226 // Macro uses will remove items from this set, and the remaining
1227 // items will be reported as `unused_macros`.
1228 fn insert_unused_macro(
1233 rule_spans: &[(usize, Span)],
1235 if !ident.as_str().starts_with('_') {
1236 self.r.unused_macros.insert(def_id, (node_id, ident));
1237 for (rule_i, rule_span) in rule_spans.iter() {
1238 self.r.unused_macro_rules.insert((def_id, *rule_i), (ident, *rule_span));
1243 fn define_macro(&mut self, item: &ast::Item) -> MacroRulesScopeRef<'a> {
1244 let parent_scope = self.parent_scope;
1245 let expansion = parent_scope.expansion;
1246 let def_id = self.r.local_def_id(item.id);
1247 let (ext, ident, span, macro_rules, rule_spans) = match &item.kind {
1248 ItemKind::MacroDef(def) => {
1249 let (ext, rule_spans) = self.r.compile_macro(item, self.r.session.edition());
1250 let ext = Lrc::new(ext);
1251 (ext, item.ident, item.span, def.macro_rules, rule_spans)
1253 ItemKind::Fn(..) => match self.proc_macro_stub(item) {
1254 Some((macro_kind, ident, span)) => {
1255 self.r.proc_macro_stubs.insert(def_id);
1256 (self.r.dummy_ext(macro_kind), ident, span, false, Vec::new())
1258 None => return parent_scope.macro_rules,
1260 _ => unreachable!(),
1263 let res = Res::Def(DefKind::Macro(ext.macro_kind()), def_id.to_def_id());
1264 self.r.macro_map.insert(def_id.to_def_id(), MacroData { ext, macro_rules });
1265 self.r.local_macro_def_scopes.insert(def_id, parent_scope.module);
1268 let ident = ident.normalize_to_macros_2_0();
1269 self.r.macro_names.insert(ident);
1270 let is_macro_export = self.r.session.contains_name(&item.attrs, sym::macro_export);
1271 let vis = if is_macro_export {
1272 ty::Visibility::Public
1274 ty::Visibility::Restricted(CRATE_DEF_ID)
1276 let binding = (res, vis, span, expansion).to_name_binding(self.r.arenas);
1277 self.r.set_binding_parent_module(binding, parent_scope.module);
1278 if is_macro_export {
1279 let module = self.r.graph_root;
1280 self.r.define(module, ident, MacroNS, (res, vis, span, expansion, IsMacroExport));
1282 self.r.check_reserved_macro_name(ident, res);
1283 self.insert_unused_macro(ident, def_id, item.id, &rule_spans);
1285 self.r.visibilities.insert(def_id, vis);
1286 let scope = self.r.arenas.alloc_macro_rules_scope(MacroRulesScope::Binding(
1287 self.r.arenas.alloc_macro_rules_binding(MacroRulesBinding {
1288 parent_macro_rules_scope: parent_scope.macro_rules,
1293 self.r.macro_rules_scopes.insert(def_id, scope);
1296 let module = parent_scope.module;
1297 let vis = match item.kind {
1298 // Visibilities must not be resolved non-speculatively twice
1299 // and we already resolved this one as a `fn` item visibility.
1300 ItemKind::Fn(..) => {
1301 self.try_resolve_visibility(&item.vis, false).unwrap_or(ty::Visibility::Public)
1303 _ => self.resolve_visibility(&item.vis),
1305 if !vis.is_public() {
1306 self.insert_unused_macro(ident, def_id, item.id, &rule_spans);
1308 self.r.define(module, ident, MacroNS, (res, vis, span, expansion));
1309 self.r.visibilities.insert(def_id, vis);
1310 self.parent_scope.macro_rules
1315 macro_rules! method {
1316 ($visit:ident: $ty:ty, $invoc:path, $walk:ident) => {
1317 fn $visit(&mut self, node: &'b $ty) {
1318 if let $invoc(..) = node.kind {
1319 self.visit_invoc(node.id);
1321 visit::$walk(self, node);
1327 impl<'a, 'b> Visitor<'b> for BuildReducedGraphVisitor<'a, 'b> {
1328 method!(visit_expr: ast::Expr, ast::ExprKind::MacCall, walk_expr);
1329 method!(visit_pat: ast::Pat, ast::PatKind::MacCall, walk_pat);
1330 method!(visit_ty: ast::Ty, ast::TyKind::MacCall, walk_ty);
1332 fn visit_item(&mut self, item: &'b Item) {
1333 let orig_module_scope = self.parent_scope.module;
1334 self.parent_scope.macro_rules = match item.kind {
1335 ItemKind::MacroDef(..) => {
1336 let macro_rules_scope = self.define_macro(item);
1337 visit::walk_item(self, item);
1340 ItemKind::MacCall(..) => {
1341 let macro_rules_scope = self.visit_invoc_in_module(item.id);
1342 visit::walk_item(self, item);
1346 let orig_macro_rules_scope = self.parent_scope.macro_rules;
1347 self.build_reduced_graph_for_item(item);
1348 visit::walk_item(self, item);
1350 ItemKind::Mod(..) if self.contains_macro_use(&item.attrs) => {
1351 self.parent_scope.macro_rules
1353 _ => orig_macro_rules_scope,
1357 self.parent_scope.module = orig_module_scope;
1360 fn visit_stmt(&mut self, stmt: &'b ast::Stmt) {
1361 if let ast::StmtKind::MacCall(..) = stmt.kind {
1362 self.parent_scope.macro_rules = self.visit_invoc_in_module(stmt.id);
1364 visit::walk_stmt(self, stmt);
1368 fn visit_foreign_item(&mut self, foreign_item: &'b ForeignItem) {
1369 if let ForeignItemKind::MacCall(_) = foreign_item.kind {
1370 self.visit_invoc_in_module(foreign_item.id);
1374 self.build_reduced_graph_for_foreign_item(foreign_item);
1375 visit::walk_foreign_item(self, foreign_item);
1378 fn visit_block(&mut self, block: &'b Block) {
1379 let orig_current_module = self.parent_scope.module;
1380 let orig_current_macro_rules_scope = self.parent_scope.macro_rules;
1381 self.build_reduced_graph_for_block(block);
1382 visit::walk_block(self, block);
1383 self.parent_scope.module = orig_current_module;
1384 self.parent_scope.macro_rules = orig_current_macro_rules_scope;
1387 fn visit_assoc_item(&mut self, item: &'b AssocItem, ctxt: AssocCtxt) {
1388 if let AssocItemKind::MacCall(_) = item.kind {
1390 AssocCtxt::Trait => {
1391 self.visit_invoc_in_module(item.id);
1393 AssocCtxt::Impl => {
1394 self.visit_invoc(item.id);
1400 let vis = self.resolve_visibility(&item.vis);
1401 let local_def_id = self.r.local_def_id(item.id);
1402 let def_id = local_def_id.to_def_id();
1404 if !(ctxt == AssocCtxt::Impl
1405 && matches!(item.vis.kind, ast::VisibilityKind::Inherited)
1409 .contains(&ty::DefIdTree::local_parent(&*self.r, local_def_id)))
1411 // Trait impl item visibility is inherited from its trait when not specified
1412 // explicitly. In that case we cannot determine it here in early resolve,
1413 // so we leave a hole in the visibility table to be filled later.
1414 self.r.visibilities.insert(local_def_id, vis);
1417 if ctxt == AssocCtxt::Trait {
1418 let (def_kind, ns) = match item.kind {
1419 AssocItemKind::Const(..) => (DefKind::AssocConst, ValueNS),
1420 AssocItemKind::Fn(box Fn { ref sig, .. }) => {
1421 if sig.decl.has_self() {
1422 self.r.has_self.insert(def_id);
1424 (DefKind::AssocFn, ValueNS)
1426 AssocItemKind::TyAlias(..) => (DefKind::AssocTy, TypeNS),
1427 AssocItemKind::MacCall(_) => bug!(), // handled above
1430 let parent = self.parent_scope.module;
1431 let expansion = self.parent_scope.expansion;
1432 let res = Res::Def(def_kind, def_id);
1433 self.r.define(parent, item.ident, ns, (res, vis, item.span, expansion));
1436 visit::walk_assoc_item(self, item, ctxt);
1439 fn visit_attribute(&mut self, attr: &'b ast::Attribute) {
1440 if !attr.is_doc_comment() && attr::is_builtin_attr(attr) {
1443 .push((attr.get_normal_item().path.segments[0].ident, self.parent_scope));
1445 visit::walk_attribute(self, attr);
1448 fn visit_arm(&mut self, arm: &'b ast::Arm) {
1449 if arm.is_placeholder {
1450 self.visit_invoc(arm.id);
1452 visit::walk_arm(self, arm);
1456 fn visit_expr_field(&mut self, f: &'b ast::ExprField) {
1457 if f.is_placeholder {
1458 self.visit_invoc(f.id);
1460 visit::walk_expr_field(self, f);
1464 fn visit_pat_field(&mut self, fp: &'b ast::PatField) {
1465 if fp.is_placeholder {
1466 self.visit_invoc(fp.id);
1468 visit::walk_pat_field(self, fp);
1472 fn visit_generic_param(&mut self, param: &'b ast::GenericParam) {
1473 if param.is_placeholder {
1474 self.visit_invoc(param.id);
1476 visit::walk_generic_param(self, param);
1480 fn visit_param(&mut self, p: &'b ast::Param) {
1481 if p.is_placeholder {
1482 self.visit_invoc(p.id);
1484 visit::walk_param(self, p);
1488 fn visit_field_def(&mut self, sf: &'b ast::FieldDef) {
1489 if sf.is_placeholder {
1490 self.visit_invoc(sf.id);
1492 let vis = self.resolve_visibility(&sf.vis);
1493 self.r.visibilities.insert(self.r.local_def_id(sf.id), vis);
1494 visit::walk_field_def(self, sf);
1498 // Constructs the reduced graph for one variant. Variants exist in the
1499 // type and value namespaces.
1500 fn visit_variant(&mut self, variant: &'b ast::Variant) {
1501 if variant.is_placeholder {
1502 self.visit_invoc_in_module(variant.id);
1506 let parent = self.parent_scope.module;
1507 let expn_id = self.parent_scope.expansion;
1508 let ident = variant.ident;
1510 // Define a name in the type namespace.
1511 let def_id = self.r.local_def_id(variant.id);
1512 let res = Res::Def(DefKind::Variant, def_id.to_def_id());
1513 let vis = self.resolve_visibility(&variant.vis);
1514 self.r.define(parent, ident, TypeNS, (res, vis, variant.span, expn_id));
1515 self.r.visibilities.insert(def_id, vis);
1517 // If the variant is marked as non_exhaustive then lower the visibility to within the crate.
1518 let ctor_vis = if vis.is_public()
1519 && self.r.session.contains_name(&variant.attrs, sym::non_exhaustive)
1521 ty::Visibility::Restricted(CRATE_DEF_ID)
1526 // Define a constructor name in the value namespace.
1527 // Braced variants, unlike structs, generate unusable names in
1528 // value namespace, they are reserved for possible future use.
1529 // It's ok to use the variant's id as a ctor id since an
1530 // error will be reported on any use of such resolution anyway.
1531 let ctor_node_id = variant.data.ctor_id().unwrap_or(variant.id);
1532 let ctor_def_id = self.r.local_def_id(ctor_node_id);
1533 let ctor_kind = CtorKind::from_ast(&variant.data);
1534 let ctor_res = Res::Def(DefKind::Ctor(CtorOf::Variant, ctor_kind), ctor_def_id.to_def_id());
1535 self.r.define(parent, ident, ValueNS, (ctor_res, ctor_vis, variant.span, expn_id));
1536 if ctor_def_id != def_id {
1537 self.r.visibilities.insert(ctor_def_id, ctor_vis);
1539 // Record field names for error reporting.
1540 self.insert_field_names_local(ctor_def_id.to_def_id(), &variant.data);
1542 visit::walk_variant(self, variant);
1545 fn visit_crate(&mut self, krate: &'b ast::Crate) {
1546 if krate.is_placeholder {
1547 self.visit_invoc_in_module(krate.id);
1549 visit::walk_crate(self, krate);
1550 self.contains_macro_use(&krate.attrs);