1 #![doc(html_root_url = "https://doc.rust-lang.org/nightly/nightly-rustc/")]
2 #![feature(associated_type_defaults)]
3 #![feature(control_flow_enum)]
4 #![feature(rustc_private)]
5 #![feature(try_blocks)]
6 #![recursion_limit = "256"]
7 #![allow(rustc::potential_query_instability)]
8 #![cfg_attr(not(bootstrap), deny(rustc::untranslatable_diagnostic))]
9 #![cfg_attr(not(bootstrap), deny(rustc::diagnostic_outside_of_impl))]
13 use rustc_ast::MacroDef;
14 use rustc_attr as attr;
15 use rustc_data_structures::fx::FxHashSet;
16 use rustc_data_structures::intern::Interned;
18 use rustc_hir::def::{DefKind, Res};
19 use rustc_hir::def_id::{DefId, LocalDefId, LocalDefIdSet, CRATE_DEF_ID};
20 use rustc_hir::intravisit::{self, Visitor};
21 use rustc_hir::{AssocItemKind, HirIdSet, ItemId, Node, PatKind};
22 use rustc_middle::bug;
23 use rustc_middle::hir::nested_filter;
24 use rustc_middle::middle::privacy::{AccessLevel, AccessLevels};
25 use rustc_middle::span_bug;
26 use rustc_middle::thir::abstract_const::Node as ACNode;
27 use rustc_middle::ty::query::Providers;
28 use rustc_middle::ty::subst::InternalSubsts;
29 use rustc_middle::ty::{self, Const, DefIdTree, GenericParamDefKind};
30 use rustc_middle::ty::{TraitRef, Ty, TyCtxt, TypeFoldable, TypeSuperFoldable, TypeVisitor};
31 use rustc_session::lint;
32 use rustc_span::hygiene::Transparency;
33 use rustc_span::symbol::{kw, Ident};
35 use rustc_trait_selection::traits::const_evaluatable::{self, AbstractConst};
37 use std::marker::PhantomData;
38 use std::ops::ControlFlow;
39 use std::{cmp, fmt, mem};
42 FieldIsPrivate, FieldIsPrivateLabel, InPublicInterface, InPublicInterfaceTraits, ItemIsPrivate,
46 ////////////////////////////////////////////////////////////////////////////////
47 /// Generic infrastructure used to implement specific visitors below.
48 ////////////////////////////////////////////////////////////////////////////////
50 /// Implemented to visit all `DefId`s in a type.
51 /// Visiting `DefId`s is useful because visibilities and reachabilities are attached to them.
52 /// The idea is to visit "all components of a type", as documented in
53 /// <https://github.com/rust-lang/rfcs/blob/master/text/2145-type-privacy.md#how-to-determine-visibility-of-a-type>.
54 /// The default type visitor (`TypeVisitor`) does most of the job, but it has some shortcomings.
55 /// First, it doesn't have overridable `fn visit_trait_ref`, so we have to catch trait `DefId`s
56 /// manually. Second, it doesn't visit some type components like signatures of fn types, or traits
57 /// in `impl Trait`, see individual comments in `DefIdVisitorSkeleton::visit_ty`.
58 trait DefIdVisitor<'tcx> {
61 fn tcx(&self) -> TyCtxt<'tcx>;
62 fn shallow(&self) -> bool {
65 fn skip_assoc_tys(&self) -> bool {
72 descr: &dyn fmt::Display,
73 ) -> ControlFlow<Self::BreakTy>;
75 /// Not overridden, but used to actually visit types and traits.
76 fn skeleton(&mut self) -> DefIdVisitorSkeleton<'_, 'tcx, Self> {
77 DefIdVisitorSkeleton {
79 visited_opaque_tys: Default::default(),
80 dummy: Default::default(),
83 fn visit(&mut self, ty_fragment: impl TypeFoldable<'tcx>) -> ControlFlow<Self::BreakTy> {
84 ty_fragment.visit_with(&mut self.skeleton())
86 fn visit_trait(&mut self, trait_ref: TraitRef<'tcx>) -> ControlFlow<Self::BreakTy> {
87 self.skeleton().visit_trait(trait_ref)
89 fn visit_projection_ty(
91 projection: ty::ProjectionTy<'tcx>,
92 ) -> ControlFlow<Self::BreakTy> {
93 self.skeleton().visit_projection_ty(projection)
97 predicates: ty::GenericPredicates<'tcx>,
98 ) -> ControlFlow<Self::BreakTy> {
99 self.skeleton().visit_predicates(predicates)
103 struct DefIdVisitorSkeleton<'v, 'tcx, V: ?Sized> {
104 def_id_visitor: &'v mut V,
105 visited_opaque_tys: FxHashSet<DefId>,
106 dummy: PhantomData<TyCtxt<'tcx>>,
109 impl<'tcx, V> DefIdVisitorSkeleton<'_, 'tcx, V>
111 V: DefIdVisitor<'tcx> + ?Sized,
113 fn visit_trait(&mut self, trait_ref: TraitRef<'tcx>) -> ControlFlow<V::BreakTy> {
114 let TraitRef { def_id, substs } = trait_ref;
115 self.def_id_visitor.visit_def_id(def_id, "trait", &trait_ref.print_only_trait_path())?;
116 if self.def_id_visitor.shallow() { ControlFlow::CONTINUE } else { substs.visit_with(self) }
119 fn visit_projection_ty(
121 projection: ty::ProjectionTy<'tcx>,
122 ) -> ControlFlow<V::BreakTy> {
123 let (trait_ref, assoc_substs) =
124 projection.trait_ref_and_own_substs(self.def_id_visitor.tcx());
125 self.visit_trait(trait_ref)?;
126 if self.def_id_visitor.shallow() {
127 ControlFlow::CONTINUE
129 assoc_substs.iter().try_for_each(|subst| subst.visit_with(self))
133 fn visit_predicate(&mut self, predicate: ty::Predicate<'tcx>) -> ControlFlow<V::BreakTy> {
134 match predicate.kind().skip_binder() {
135 ty::PredicateKind::Trait(ty::TraitPredicate {
139 }) => self.visit_trait(trait_ref),
140 ty::PredicateKind::Projection(ty::ProjectionPredicate { projection_ty, term }) => {
141 term.visit_with(self)?;
142 self.visit_projection_ty(projection_ty)
144 ty::PredicateKind::TypeOutlives(ty::OutlivesPredicate(ty, _region)) => {
147 ty::PredicateKind::RegionOutlives(..) => ControlFlow::CONTINUE,
148 ty::PredicateKind::ConstEvaluatable(uv)
149 if self.def_id_visitor.tcx().features().generic_const_exprs =>
151 let tcx = self.def_id_visitor.tcx();
152 if let Ok(Some(ct)) = AbstractConst::new(tcx, uv) {
153 self.visit_abstract_const_expr(tcx, ct)?;
155 ControlFlow::CONTINUE
157 ty::PredicateKind::WellFormed(arg) => arg.visit_with(self),
158 _ => bug!("unexpected predicate: {:?}", predicate),
162 fn visit_abstract_const_expr(
165 ct: AbstractConst<'tcx>,
166 ) -> ControlFlow<V::BreakTy> {
167 const_evaluatable::walk_abstract_const(tcx, ct, |node| match node.root(tcx) {
168 ACNode::Leaf(leaf) => self.visit_const(leaf),
169 ACNode::Cast(_, _, ty) => self.visit_ty(ty),
170 ACNode::Binop(..) | ACNode::UnaryOp(..) | ACNode::FunctionCall(_, _) => {
171 ControlFlow::CONTINUE
178 predicates: ty::GenericPredicates<'tcx>,
179 ) -> ControlFlow<V::BreakTy> {
180 let ty::GenericPredicates { parent: _, predicates } = predicates;
181 predicates.iter().try_for_each(|&(predicate, _span)| self.visit_predicate(predicate))
185 impl<'tcx, V> TypeVisitor<'tcx> for DefIdVisitorSkeleton<'_, 'tcx, V>
187 V: DefIdVisitor<'tcx> + ?Sized,
189 type BreakTy = V::BreakTy;
191 fn visit_ty(&mut self, ty: Ty<'tcx>) -> ControlFlow<V::BreakTy> {
192 let tcx = self.def_id_visitor.tcx();
193 // InternalSubsts are not visited here because they are visited below
194 // in `super_visit_with`.
196 ty::Adt(ty::AdtDef(Interned(&ty::AdtDefData { did: def_id, .. }, _)), ..)
197 | ty::Foreign(def_id)
198 | ty::FnDef(def_id, ..)
199 | ty::Closure(def_id, ..)
200 | ty::Generator(def_id, ..) => {
201 self.def_id_visitor.visit_def_id(def_id, "type", &ty)?;
202 if self.def_id_visitor.shallow() {
203 return ControlFlow::CONTINUE;
205 // Default type visitor doesn't visit signatures of fn types.
206 // Something like `fn() -> Priv {my_func}` is considered a private type even if
207 // `my_func` is public, so we need to visit signatures.
208 if let ty::FnDef(..) = ty.kind() {
209 tcx.fn_sig(def_id).visit_with(self)?;
211 // Inherent static methods don't have self type in substs.
212 // Something like `fn() {my_method}` type of the method
213 // `impl Pub<Priv> { pub fn my_method() {} }` is considered a private type,
214 // so we need to visit the self type additionally.
215 if let Some(assoc_item) = tcx.opt_associated_item(def_id) {
216 if let ty::ImplContainer(impl_def_id) = assoc_item.container {
217 tcx.type_of(impl_def_id).visit_with(self)?;
221 ty::Projection(proj) => {
222 if self.def_id_visitor.skip_assoc_tys() {
223 // Visitors searching for minimal visibility/reachability want to
224 // conservatively approximate associated types like `<Type as Trait>::Alias`
225 // as visible/reachable even if both `Type` and `Trait` are private.
226 // Ideally, associated types should be substituted in the same way as
227 // free type aliases, but this isn't done yet.
228 return ControlFlow::CONTINUE;
230 // This will also visit substs if necessary, so we don't need to recurse.
231 return self.visit_projection_ty(proj);
233 ty::Dynamic(predicates, ..) => {
234 // All traits in the list are considered the "primary" part of the type
235 // and are visited by shallow visitors.
236 for predicate in predicates {
237 let trait_ref = match predicate.skip_binder() {
238 ty::ExistentialPredicate::Trait(trait_ref) => trait_ref,
239 ty::ExistentialPredicate::Projection(proj) => proj.trait_ref(tcx),
240 ty::ExistentialPredicate::AutoTrait(def_id) => {
241 ty::ExistentialTraitRef { def_id, substs: InternalSubsts::empty() }
244 let ty::ExistentialTraitRef { def_id, substs: _ } = trait_ref;
245 self.def_id_visitor.visit_def_id(def_id, "trait", &trait_ref)?;
248 ty::Opaque(def_id, ..) => {
249 // Skip repeated `Opaque`s to avoid infinite recursion.
250 if self.visited_opaque_tys.insert(def_id) {
251 // The intent is to treat `impl Trait1 + Trait2` identically to
252 // `dyn Trait1 + Trait2`. Therefore we ignore def-id of the opaque type itself
253 // (it either has no visibility, or its visibility is insignificant, like
254 // visibilities of type aliases) and recurse into bounds instead to go
255 // through the trait list (default type visitor doesn't visit those traits).
256 // All traits in the list are considered the "primary" part of the type
257 // and are visited by shallow visitors.
258 self.visit_predicates(ty::GenericPredicates {
260 predicates: tcx.explicit_item_bounds(def_id),
264 // These types don't have their own def-ids (but may have subcomponents
265 // with def-ids that should be visited recursively).
281 | ty::GeneratorWitness(..) => {}
282 ty::Bound(..) | ty::Placeholder(..) | ty::Infer(..) => {
283 bug!("unexpected type: {:?}", ty)
287 if self.def_id_visitor.shallow() {
288 ControlFlow::CONTINUE
290 ty.super_visit_with(self)
294 fn visit_const(&mut self, c: Const<'tcx>) -> ControlFlow<Self::BreakTy> {
295 self.visit_ty(c.ty())?;
296 let tcx = self.def_id_visitor.tcx();
297 if let Ok(Some(ct)) = AbstractConst::from_const(tcx, c) {
298 self.visit_abstract_const_expr(tcx, ct)?;
300 ControlFlow::CONTINUE
304 fn min(vis1: ty::Visibility, vis2: ty::Visibility, tcx: TyCtxt<'_>) -> ty::Visibility {
305 if vis1.is_at_least(vis2, tcx) { vis2 } else { vis1 }
308 ////////////////////////////////////////////////////////////////////////////////
309 /// Visitor used to determine impl visibility and reachability.
310 ////////////////////////////////////////////////////////////////////////////////
312 struct FindMin<'a, 'tcx, VL: VisibilityLike> {
314 access_levels: &'a AccessLevels,
318 impl<'a, 'tcx, VL: VisibilityLike> DefIdVisitor<'tcx> for FindMin<'a, 'tcx, VL> {
319 fn tcx(&self) -> TyCtxt<'tcx> {
322 fn shallow(&self) -> bool {
325 fn skip_assoc_tys(&self) -> bool {
332 _descr: &dyn fmt::Display,
333 ) -> ControlFlow<Self::BreakTy> {
334 self.min = VL::new_min(self, def_id);
335 ControlFlow::CONTINUE
339 trait VisibilityLike: Sized {
341 const SHALLOW: bool = false;
342 fn new_min(find: &FindMin<'_, '_, Self>, def_id: DefId) -> Self;
344 // Returns an over-approximation (`skip_assoc_tys` = true) of visibility due to
345 // associated types for which we can't determine visibility precisely.
346 fn of_impl(def_id: LocalDefId, tcx: TyCtxt<'_>, access_levels: &AccessLevels) -> Self {
347 let mut find = FindMin { tcx, access_levels, min: Self::MAX };
348 find.visit(tcx.type_of(def_id));
349 if let Some(trait_ref) = tcx.impl_trait_ref(def_id) {
350 find.visit_trait(trait_ref);
355 impl VisibilityLike for ty::Visibility {
356 const MAX: Self = ty::Visibility::Public;
357 fn new_min(find: &FindMin<'_, '_, Self>, def_id: DefId) -> Self {
358 min(find.tcx.visibility(def_id), find.min, find.tcx)
361 impl VisibilityLike for Option<AccessLevel> {
362 const MAX: Self = Some(AccessLevel::Public);
363 // Type inference is very smart sometimes.
364 // It can make an impl reachable even some components of its type or trait are unreachable.
365 // E.g. methods of `impl ReachableTrait<UnreachableTy> for ReachableTy<UnreachableTy> { ... }`
366 // can be usable from other crates (#57264). So we skip substs when calculating reachability
367 // and consider an impl reachable if its "shallow" type and trait are reachable.
369 // The assumption we make here is that type-inference won't let you use an impl without knowing
370 // both "shallow" version of its self type and "shallow" version of its trait if it exists
371 // (which require reaching the `DefId`s in them).
372 const SHALLOW: bool = true;
373 fn new_min(find: &FindMin<'_, '_, Self>, def_id: DefId) -> Self {
375 if let Some(def_id) = def_id.as_local() {
376 find.access_levels.map.get(&def_id).copied()
385 ////////////////////////////////////////////////////////////////////////////////
386 /// The embargo visitor, used to determine the exports of the AST.
387 ////////////////////////////////////////////////////////////////////////////////
389 struct EmbargoVisitor<'tcx> {
392 /// Accessibility levels for reachable nodes.
393 access_levels: AccessLevels,
394 /// A set of pairs corresponding to modules, where the first module is
395 /// reachable via a macro that's defined in the second module. This cannot
396 /// be represented as reachable because it can't handle the following case:
398 /// pub mod n { // Should be `Public`
399 /// pub(crate) mod p { // Should *not* be accessible
400 /// pub fn f() -> i32 { 12 } // Must be `Reachable`
406 macro_reachable: FxHashSet<(LocalDefId, LocalDefId)>,
407 /// Previous accessibility level; `None` means unreachable.
408 prev_level: Option<AccessLevel>,
409 /// Has something changed in the level map?
413 struct ReachEverythingInTheInterfaceVisitor<'a, 'tcx> {
414 access_level: Option<AccessLevel>,
415 item_def_id: LocalDefId,
416 ev: &'a mut EmbargoVisitor<'tcx>,
419 impl<'tcx> EmbargoVisitor<'tcx> {
420 fn get(&self, def_id: LocalDefId) -> Option<AccessLevel> {
421 self.access_levels.map.get(&def_id).copied()
424 fn update_with_hir_id(
427 level: Option<AccessLevel>,
428 ) -> Option<AccessLevel> {
429 let def_id = self.tcx.hir().local_def_id(hir_id);
430 self.update(def_id, level)
433 /// Updates node level and returns the updated level.
434 fn update(&mut self, def_id: LocalDefId, level: Option<AccessLevel>) -> Option<AccessLevel> {
435 let old_level = self.get(def_id);
436 // Accessibility levels can only grow.
437 if level > old_level {
438 self.access_levels.map.insert(def_id, level.unwrap());
449 access_level: Option<AccessLevel>,
450 ) -> ReachEverythingInTheInterfaceVisitor<'_, 'tcx> {
451 ReachEverythingInTheInterfaceVisitor {
452 access_level: cmp::min(access_level, Some(AccessLevel::Reachable)),
458 // We have to make sure that the items that macros might reference
459 // are reachable, since they might be exported transitively.
460 fn update_reachability_from_macro(&mut self, local_def_id: LocalDefId, md: &MacroDef) {
461 // Non-opaque macros cannot make other items more accessible than they already are.
463 let hir_id = self.tcx.hir().local_def_id_to_hir_id(local_def_id);
464 let attrs = self.tcx.hir().attrs(hir_id);
465 if attr::find_transparency(attrs, md.macro_rules).0 != Transparency::Opaque {
469 let macro_module_def_id = self.tcx.local_parent(local_def_id);
470 if self.tcx.opt_def_kind(macro_module_def_id) != Some(DefKind::Mod) {
471 // The macro's parent doesn't correspond to a `mod`, return early (#63164, #65252).
475 if self.get(local_def_id).is_none() {
479 // Since we are starting from an externally visible module,
480 // all the parents in the loop below are also guaranteed to be modules.
481 let mut module_def_id = macro_module_def_id;
483 let changed_reachability =
484 self.update_macro_reachable(module_def_id, macro_module_def_id);
485 if changed_reachability || module_def_id == CRATE_DEF_ID {
488 module_def_id = self.tcx.local_parent(module_def_id);
492 /// Updates the item as being reachable through a macro defined in the given
493 /// module. Returns `true` if the level has changed.
494 fn update_macro_reachable(
496 module_def_id: LocalDefId,
497 defining_mod: LocalDefId,
499 if self.macro_reachable.insert((module_def_id, defining_mod)) {
500 self.update_macro_reachable_mod(module_def_id, defining_mod);
507 fn update_macro_reachable_mod(&mut self, module_def_id: LocalDefId, defining_mod: LocalDefId) {
508 let module = self.tcx.hir().get_module(module_def_id).0;
509 for item_id in module.item_ids {
510 let def_kind = self.tcx.def_kind(item_id.def_id);
511 let vis = self.tcx.visibility(item_id.def_id);
512 self.update_macro_reachable_def(item_id.def_id, def_kind, vis, defining_mod);
514 if let Some(exports) = self.tcx.module_reexports(module_def_id) {
515 for export in exports {
516 if export.vis.is_accessible_from(defining_mod.to_def_id(), self.tcx) {
517 if let Res::Def(def_kind, def_id) = export.res {
518 if let Some(def_id) = def_id.as_local() {
519 let vis = self.tcx.visibility(def_id.to_def_id());
520 self.update_macro_reachable_def(def_id, def_kind, vis, defining_mod);
528 fn update_macro_reachable_def(
535 let level = Some(AccessLevel::Reachable);
537 self.update(def_id, level);
540 // No type privacy, so can be directly marked as reachable.
541 DefKind::Const | DefKind::Static(_) | DefKind::TraitAlias | DefKind::TyAlias => {
542 if vis.is_accessible_from(module.to_def_id(), self.tcx) {
543 self.update(def_id, level);
547 // Hygiene isn't really implemented for `macro_rules!` macros at the
548 // moment. Accordingly, marking them as reachable is unwise. `macro` macros
549 // have normal hygiene, so we can treat them like other items without type
550 // privacy and mark them reachable.
551 DefKind::Macro(_) => {
552 let item = self.tcx.hir().expect_item(def_id);
553 if let hir::ItemKind::Macro(MacroDef { macro_rules: false, .. }, _) = item.kind {
554 if vis.is_accessible_from(module.to_def_id(), self.tcx) {
555 self.update(def_id, level);
560 // We can't use a module name as the final segment of a path, except
561 // in use statements. Since re-export checking doesn't consider
562 // hygiene these don't need to be marked reachable. The contents of
563 // the module, however may be reachable.
565 if vis.is_accessible_from(module.to_def_id(), self.tcx) {
566 self.update_macro_reachable(def_id, module);
570 DefKind::Struct | DefKind::Union => {
571 // While structs and unions have type privacy, their fields do not.
573 let item = self.tcx.hir().expect_item(def_id);
574 if let hir::ItemKind::Struct(ref struct_def, _)
575 | hir::ItemKind::Union(ref struct_def, _) = item.kind
577 for field in struct_def.fields() {
578 let def_id = self.tcx.hir().local_def_id(field.hir_id);
579 let field_vis = self.tcx.visibility(def_id);
580 if field_vis.is_accessible_from(module.to_def_id(), self.tcx) {
581 self.reach(def_id, level).ty();
585 bug!("item {:?} with DefKind {:?}", item, def_kind);
590 // These have type privacy, so are not reachable unless they're
591 // public, or are not namespaced at all.
594 | DefKind::ConstParam
595 | DefKind::Ctor(_, _)
604 | DefKind::LifetimeParam
605 | DefKind::ExternCrate
607 | DefKind::ForeignMod
609 | DefKind::InlineConst
614 | DefKind::Generator => (),
619 impl<'tcx> Visitor<'tcx> for EmbargoVisitor<'tcx> {
620 type NestedFilter = nested_filter::All;
622 /// We want to visit items in the context of their containing
623 /// module and so forth, so supply a crate for doing a deep walk.
624 fn nested_visit_map(&mut self) -> Self::Map {
628 fn visit_item(&mut self, item: &'tcx hir::Item<'tcx>) {
629 let item_level = match item.kind {
630 hir::ItemKind::Impl { .. } => {
632 Option::<AccessLevel>::of_impl(item.def_id, self.tcx, &self.access_levels);
633 self.update(item.def_id, impl_level)
635 _ => self.get(item.def_id),
638 // Update levels of nested things.
640 hir::ItemKind::Enum(ref def, _) => {
641 for variant in def.variants {
642 let variant_level = self.update_with_hir_id(variant.id, item_level);
643 if let Some(ctor_hir_id) = variant.data.ctor_hir_id() {
644 self.update_with_hir_id(ctor_hir_id, item_level);
646 for field in variant.data.fields() {
647 self.update_with_hir_id(field.hir_id, variant_level);
651 hir::ItemKind::Impl(ref impl_) => {
652 for impl_item_ref in impl_.items {
653 if impl_.of_trait.is_some()
654 || self.tcx.visibility(impl_item_ref.id.def_id) == ty::Visibility::Public
656 self.update(impl_item_ref.id.def_id, item_level);
660 hir::ItemKind::Trait(.., trait_item_refs) => {
661 for trait_item_ref in trait_item_refs {
662 self.update(trait_item_ref.id.def_id, item_level);
665 hir::ItemKind::Struct(ref def, _) | hir::ItemKind::Union(ref def, _) => {
666 if let Some(ctor_hir_id) = def.ctor_hir_id() {
667 self.update_with_hir_id(ctor_hir_id, item_level);
669 for field in def.fields() {
670 let def_id = self.tcx.hir().local_def_id(field.hir_id);
671 let vis = self.tcx.visibility(def_id);
673 self.update_with_hir_id(field.hir_id, item_level);
677 hir::ItemKind::Macro(ref macro_def, _) => {
678 self.update_reachability_from_macro(item.def_id, macro_def);
680 hir::ItemKind::ForeignMod { items, .. } => {
681 for foreign_item in items {
682 if self.tcx.visibility(foreign_item.id.def_id) == ty::Visibility::Public {
683 self.update(foreign_item.id.def_id, item_level);
688 hir::ItemKind::OpaqueTy(..)
689 | hir::ItemKind::Use(..)
690 | hir::ItemKind::Static(..)
691 | hir::ItemKind::Const(..)
692 | hir::ItemKind::GlobalAsm(..)
693 | hir::ItemKind::TyAlias(..)
694 | hir::ItemKind::Mod(..)
695 | hir::ItemKind::TraitAlias(..)
696 | hir::ItemKind::Fn(..)
697 | hir::ItemKind::ExternCrate(..) => {}
700 // Mark all items in interfaces of reachable items as reachable.
702 // The interface is empty.
703 hir::ItemKind::Macro(..) | hir::ItemKind::ExternCrate(..) => {}
704 // All nested items are checked by `visit_item`.
705 hir::ItemKind::Mod(..) => {}
706 // Handled in the access level of in rustc_resolve
707 hir::ItemKind::Use(..) => {}
708 // The interface is empty.
709 hir::ItemKind::GlobalAsm(..) => {}
710 hir::ItemKind::OpaqueTy(..) => {
711 // HACK(jynelson): trying to infer the type of `impl trait` breaks `async-std` (and `pub async fn` in general)
712 // Since rustdoc never needs to do codegen and doesn't care about link-time reachability,
713 // mark this as unreachable.
714 // See https://github.com/rust-lang/rust/issues/75100
715 if !self.tcx.sess.opts.actually_rustdoc {
716 // FIXME: This is some serious pessimization intended to workaround deficiencies
717 // in the reachability pass (`middle/reachable.rs`). Types are marked as link-time
718 // reachable if they are returned via `impl Trait`, even from private functions.
720 cmp::max(item_level, Some(AccessLevel::ReachableFromImplTrait));
721 self.reach(item.def_id, exist_level).generics().predicates().ty();
725 hir::ItemKind::Const(..)
726 | hir::ItemKind::Static(..)
727 | hir::ItemKind::Fn(..)
728 | hir::ItemKind::TyAlias(..) => {
729 if item_level.is_some() {
730 self.reach(item.def_id, item_level).generics().predicates().ty();
733 hir::ItemKind::Trait(.., trait_item_refs) => {
734 if item_level.is_some() {
735 self.reach(item.def_id, item_level).generics().predicates();
737 for trait_item_ref in trait_item_refs {
738 let mut reach = self.reach(trait_item_ref.id.def_id, item_level);
739 reach.generics().predicates();
741 if trait_item_ref.kind == AssocItemKind::Type
742 && !trait_item_ref.defaultness.has_value()
751 hir::ItemKind::TraitAlias(..) => {
752 if item_level.is_some() {
753 self.reach(item.def_id, item_level).generics().predicates();
756 // Visit everything except for private impl items.
757 hir::ItemKind::Impl(ref impl_) => {
758 if item_level.is_some() {
759 self.reach(item.def_id, item_level).generics().predicates().ty().trait_ref();
761 for impl_item_ref in impl_.items {
762 let impl_item_level = self.get(impl_item_ref.id.def_id);
763 if impl_item_level.is_some() {
764 self.reach(impl_item_ref.id.def_id, impl_item_level)
773 // Visit everything, but enum variants have their own levels.
774 hir::ItemKind::Enum(ref def, _) => {
775 if item_level.is_some() {
776 self.reach(item.def_id, item_level).generics().predicates();
778 for variant in def.variants {
779 let variant_level = self.get(self.tcx.hir().local_def_id(variant.id));
780 if variant_level.is_some() {
781 for field in variant.data.fields() {
782 self.reach(self.tcx.hir().local_def_id(field.hir_id), variant_level)
785 // Corner case: if the variant is reachable, but its
786 // enum is not, make the enum reachable as well.
787 self.reach(item.def_id, variant_level).ty();
789 if let Some(hir_id) = variant.data.ctor_hir_id() {
790 let ctor_def_id = self.tcx.hir().local_def_id(hir_id);
791 let ctor_level = self.get(ctor_def_id);
792 if ctor_level.is_some() {
793 self.reach(item.def_id, ctor_level).ty();
798 // Visit everything, but foreign items have their own levels.
799 hir::ItemKind::ForeignMod { items, .. } => {
800 for foreign_item in items {
801 let foreign_item_level = self.get(foreign_item.id.def_id);
802 if foreign_item_level.is_some() {
803 self.reach(foreign_item.id.def_id, foreign_item_level)
810 // Visit everything except for private fields.
811 hir::ItemKind::Struct(ref struct_def, _) | hir::ItemKind::Union(ref struct_def, _) => {
812 if item_level.is_some() {
813 self.reach(item.def_id, item_level).generics().predicates();
814 for field in struct_def.fields() {
815 let def_id = self.tcx.hir().local_def_id(field.hir_id);
816 let field_level = self.get(def_id);
817 if field_level.is_some() {
818 self.reach(def_id, field_level).ty();
822 if let Some(hir_id) = struct_def.ctor_hir_id() {
823 let ctor_def_id = self.tcx.hir().local_def_id(hir_id);
824 let ctor_level = self.get(ctor_def_id);
825 if ctor_level.is_some() {
826 self.reach(item.def_id, ctor_level).ty();
832 let orig_level = mem::replace(&mut self.prev_level, item_level);
833 intravisit::walk_item(self, item);
834 self.prev_level = orig_level;
837 fn visit_block(&mut self, b: &'tcx hir::Block<'tcx>) {
838 // Blocks can have public items, for example impls, but they always
839 // start as completely private regardless of publicity of a function,
840 // constant, type, field, etc., in which this block resides.
841 let orig_level = mem::replace(&mut self.prev_level, None);
842 intravisit::walk_block(self, b);
843 self.prev_level = orig_level;
847 impl ReachEverythingInTheInterfaceVisitor<'_, '_> {
848 fn generics(&mut self) -> &mut Self {
849 for param in &self.ev.tcx.generics_of(self.item_def_id).params {
851 GenericParamDefKind::Lifetime => {}
852 GenericParamDefKind::Type { has_default, .. } => {
854 self.visit(self.ev.tcx.type_of(param.def_id));
857 GenericParamDefKind::Const { has_default } => {
858 self.visit(self.ev.tcx.type_of(param.def_id));
860 self.visit(self.ev.tcx.const_param_default(param.def_id));
868 fn predicates(&mut self) -> &mut Self {
869 self.visit_predicates(self.ev.tcx.predicates_of(self.item_def_id));
873 fn ty(&mut self) -> &mut Self {
874 self.visit(self.ev.tcx.type_of(self.item_def_id));
878 fn trait_ref(&mut self) -> &mut Self {
879 if let Some(trait_ref) = self.ev.tcx.impl_trait_ref(self.item_def_id) {
880 self.visit_trait(trait_ref);
886 impl<'tcx> DefIdVisitor<'tcx> for ReachEverythingInTheInterfaceVisitor<'_, 'tcx> {
887 fn tcx(&self) -> TyCtxt<'tcx> {
894 _descr: &dyn fmt::Display,
895 ) -> ControlFlow<Self::BreakTy> {
896 if let Some(def_id) = def_id.as_local() {
897 if let (ty::Visibility::Public, _) | (_, Some(AccessLevel::ReachableFromImplTrait)) =
898 (self.tcx().visibility(def_id.to_def_id()), self.access_level)
900 self.ev.update(def_id, self.access_level);
903 ControlFlow::CONTINUE
907 //////////////////////////////////////////////////////////////////////////////////////
908 /// Name privacy visitor, checks privacy and reports violations.
909 /// Most of name privacy checks are performed during the main resolution phase,
910 /// or later in type checking when field accesses and associated items are resolved.
911 /// This pass performs remaining checks for fields in struct expressions and patterns.
912 //////////////////////////////////////////////////////////////////////////////////////
914 struct NamePrivacyVisitor<'tcx> {
916 maybe_typeck_results: Option<&'tcx ty::TypeckResults<'tcx>>,
917 current_item: LocalDefId,
920 impl<'tcx> NamePrivacyVisitor<'tcx> {
921 /// Gets the type-checking results for the current body.
922 /// As this will ICE if called outside bodies, only call when working with
923 /// `Expr` or `Pat` nodes (they are guaranteed to be found only in bodies).
925 fn typeck_results(&self) -> &'tcx ty::TypeckResults<'tcx> {
926 self.maybe_typeck_results
927 .expect("`NamePrivacyVisitor::typeck_results` called outside of body")
930 // Checks that a field in a struct constructor (expression or pattern) is accessible.
933 use_ctxt: Span, // syntax context of the field name at the use site
934 span: Span, // span of the field pattern, e.g., `x: 0`
935 def: ty::AdtDef<'tcx>, // definition of the struct or enum
936 field: &'tcx ty::FieldDef,
937 in_update_syntax: bool,
943 // definition of the field
944 let ident = Ident::new(kw::Empty, use_ctxt);
945 let hir_id = self.tcx.hir().local_def_id_to_hir_id(self.current_item);
946 let def_id = self.tcx.adjust_ident_and_get_scope(ident, def.did(), hir_id).1;
947 if !field.vis.is_accessible_from(def_id, self.tcx) {
948 self.tcx.sess.emit_err(FieldIsPrivate {
950 field_name: field.name,
951 variant_descr: def.variant_descr(),
952 def_path_str: self.tcx.def_path_str(def.did()),
953 label: if in_update_syntax {
954 FieldIsPrivateLabel::IsUpdateSyntax { span, field_name: field.name }
956 FieldIsPrivateLabel::Other { span }
963 impl<'tcx> Visitor<'tcx> for NamePrivacyVisitor<'tcx> {
964 type NestedFilter = nested_filter::All;
966 /// We want to visit items in the context of their containing
967 /// module and so forth, so supply a crate for doing a deep walk.
968 fn nested_visit_map(&mut self) -> Self::Map {
972 fn visit_mod(&mut self, _m: &'tcx hir::Mod<'tcx>, _s: Span, _n: hir::HirId) {
973 // Don't visit nested modules, since we run a separate visitor walk
974 // for each module in `privacy_access_levels`
977 fn visit_nested_body(&mut self, body: hir::BodyId) {
978 let old_maybe_typeck_results =
979 self.maybe_typeck_results.replace(self.tcx.typeck_body(body));
980 let body = self.tcx.hir().body(body);
981 self.visit_body(body);
982 self.maybe_typeck_results = old_maybe_typeck_results;
985 fn visit_item(&mut self, item: &'tcx hir::Item<'tcx>) {
986 let orig_current_item = mem::replace(&mut self.current_item, item.def_id);
987 intravisit::walk_item(self, item);
988 self.current_item = orig_current_item;
991 fn visit_expr(&mut self, expr: &'tcx hir::Expr<'tcx>) {
992 if let hir::ExprKind::Struct(qpath, fields, ref base) = expr.kind {
993 let res = self.typeck_results().qpath_res(qpath, expr.hir_id);
994 let adt = self.typeck_results().expr_ty(expr).ty_adt_def().unwrap();
995 let variant = adt.variant_of_res(res);
996 if let Some(base) = *base {
997 // If the expression uses FRU we need to make sure all the unmentioned fields
998 // are checked for privacy (RFC 736). Rather than computing the set of
999 // unmentioned fields, just check them all.
1000 for (vf_index, variant_field) in variant.fields.iter().enumerate() {
1001 let field = fields.iter().find(|f| {
1002 self.tcx.field_index(f.hir_id, self.typeck_results()) == vf_index
1004 let (use_ctxt, span) = match field {
1005 Some(field) => (field.ident.span, field.span),
1006 None => (base.span, base.span),
1008 self.check_field(use_ctxt, span, adt, variant_field, true);
1011 for field in fields {
1012 let use_ctxt = field.ident.span;
1013 let index = self.tcx.field_index(field.hir_id, self.typeck_results());
1014 self.check_field(use_ctxt, field.span, adt, &variant.fields[index], false);
1019 intravisit::walk_expr(self, expr);
1022 fn visit_pat(&mut self, pat: &'tcx hir::Pat<'tcx>) {
1023 if let PatKind::Struct(ref qpath, fields, _) = pat.kind {
1024 let res = self.typeck_results().qpath_res(qpath, pat.hir_id);
1025 let adt = self.typeck_results().pat_ty(pat).ty_adt_def().unwrap();
1026 let variant = adt.variant_of_res(res);
1027 for field in fields {
1028 let use_ctxt = field.ident.span;
1029 let index = self.tcx.field_index(field.hir_id, self.typeck_results());
1030 self.check_field(use_ctxt, field.span, adt, &variant.fields[index], false);
1034 intravisit::walk_pat(self, pat);
1038 ////////////////////////////////////////////////////////////////////////////////////////////
1039 /// Type privacy visitor, checks types for privacy and reports violations.
1040 /// Both explicitly written types and inferred types of expressions and patterns are checked.
1041 /// Checks are performed on "semantic" types regardless of names and their hygiene.
1042 ////////////////////////////////////////////////////////////////////////////////////////////
1044 struct TypePrivacyVisitor<'tcx> {
1046 maybe_typeck_results: Option<&'tcx ty::TypeckResults<'tcx>>,
1047 current_item: LocalDefId,
1051 impl<'tcx> TypePrivacyVisitor<'tcx> {
1052 /// Gets the type-checking results for the current body.
1053 /// As this will ICE if called outside bodies, only call when working with
1054 /// `Expr` or `Pat` nodes (they are guaranteed to be found only in bodies).
1056 fn typeck_results(&self) -> &'tcx ty::TypeckResults<'tcx> {
1057 self.maybe_typeck_results
1058 .expect("`TypePrivacyVisitor::typeck_results` called outside of body")
1061 fn item_is_accessible(&self, did: DefId) -> bool {
1062 self.tcx.visibility(did).is_accessible_from(self.current_item.to_def_id(), self.tcx)
1065 // Take node-id of an expression or pattern and check its type for privacy.
1066 fn check_expr_pat_type(&mut self, id: hir::HirId, span: Span) -> bool {
1068 let typeck_results = self.typeck_results();
1069 let result: ControlFlow<()> = try {
1070 self.visit(typeck_results.node_type(id))?;
1071 self.visit(typeck_results.node_substs(id))?;
1072 if let Some(adjustments) = typeck_results.adjustments().get(id) {
1073 adjustments.iter().try_for_each(|adjustment| self.visit(adjustment.target))?;
1079 fn check_def_id(&mut self, def_id: DefId, kind: &str, descr: &dyn fmt::Display) -> bool {
1080 let is_error = !self.item_is_accessible(def_id);
1082 self.tcx.sess.emit_err(ItemIsPrivate {
1085 descr: descr.to_string(),
1092 impl<'tcx> Visitor<'tcx> for TypePrivacyVisitor<'tcx> {
1093 type NestedFilter = nested_filter::All;
1095 /// We want to visit items in the context of their containing
1096 /// module and so forth, so supply a crate for doing a deep walk.
1097 fn nested_visit_map(&mut self) -> Self::Map {
1101 fn visit_mod(&mut self, _m: &'tcx hir::Mod<'tcx>, _s: Span, _n: hir::HirId) {
1102 // Don't visit nested modules, since we run a separate visitor walk
1103 // for each module in `privacy_access_levels`
1106 fn visit_nested_body(&mut self, body: hir::BodyId) {
1107 let old_maybe_typeck_results =
1108 self.maybe_typeck_results.replace(self.tcx.typeck_body(body));
1109 let body = self.tcx.hir().body(body);
1110 self.visit_body(body);
1111 self.maybe_typeck_results = old_maybe_typeck_results;
1114 fn visit_generic_arg(&mut self, generic_arg: &'tcx hir::GenericArg<'tcx>) {
1116 hir::GenericArg::Type(t) => self.visit_ty(t),
1117 hir::GenericArg::Infer(inf) => self.visit_infer(inf),
1118 hir::GenericArg::Lifetime(_) | hir::GenericArg::Const(_) => {}
1122 fn visit_ty(&mut self, hir_ty: &'tcx hir::Ty<'tcx>) {
1123 self.span = hir_ty.span;
1124 if let Some(typeck_results) = self.maybe_typeck_results {
1126 if self.visit(typeck_results.node_type(hir_ty.hir_id)).is_break() {
1130 // Types in signatures.
1131 // FIXME: This is very ineffective. Ideally each HIR type should be converted
1132 // into a semantic type only once and the result should be cached somehow.
1133 if self.visit(rustc_typeck::hir_ty_to_ty(self.tcx, hir_ty)).is_break() {
1138 intravisit::walk_ty(self, hir_ty);
1141 fn visit_infer(&mut self, inf: &'tcx hir::InferArg) {
1142 self.span = inf.span;
1143 if let Some(typeck_results) = self.maybe_typeck_results {
1144 if let Some(ty) = typeck_results.node_type_opt(inf.hir_id) {
1145 if self.visit(ty).is_break() {
1149 // We don't do anything for const infers here.
1152 bug!("visit_infer without typeck_results");
1154 intravisit::walk_inf(self, inf);
1157 fn visit_trait_ref(&mut self, trait_ref: &'tcx hir::TraitRef<'tcx>) {
1158 self.span = trait_ref.path.span;
1159 if self.maybe_typeck_results.is_none() {
1160 // Avoid calling `hir_trait_to_predicates` in bodies, it will ICE.
1161 // The traits' privacy in bodies is already checked as a part of trait object types.
1162 let bounds = rustc_typeck::hir_trait_to_predicates(
1165 // NOTE: This isn't really right, but the actual type doesn't matter here. It's
1166 // just required by `ty::TraitRef`.
1167 self.tcx.types.never,
1170 for (trait_predicate, _, _) in bounds.trait_bounds {
1171 if self.visit_trait(trait_predicate.skip_binder()).is_break() {
1176 for (poly_predicate, _) in bounds.projection_bounds {
1177 let pred = poly_predicate.skip_binder();
1178 let poly_pred_term = self.visit(pred.term);
1179 if poly_pred_term.is_break()
1180 || self.visit_projection_ty(pred.projection_ty).is_break()
1187 intravisit::walk_trait_ref(self, trait_ref);
1190 // Check types of expressions
1191 fn visit_expr(&mut self, expr: &'tcx hir::Expr<'tcx>) {
1192 if self.check_expr_pat_type(expr.hir_id, expr.span) {
1193 // Do not check nested expressions if the error already happened.
1197 hir::ExprKind::Assign(_, rhs, _) | hir::ExprKind::Match(rhs, ..) => {
1198 // Do not report duplicate errors for `x = y` and `match x { ... }`.
1199 if self.check_expr_pat_type(rhs.hir_id, rhs.span) {
1203 hir::ExprKind::MethodCall(segment, ..) => {
1204 // Method calls have to be checked specially.
1205 self.span = segment.ident.span;
1206 if let Some(def_id) = self.typeck_results().type_dependent_def_id(expr.hir_id) {
1207 if self.visit(self.tcx.type_of(def_id)).is_break() {
1213 .delay_span_bug(expr.span, "no type-dependent def for method call");
1219 intravisit::walk_expr(self, expr);
1222 // Prohibit access to associated items with insufficient nominal visibility.
1224 // Additionally, until better reachability analysis for macros 2.0 is available,
1225 // we prohibit access to private statics from other crates, this allows to give
1226 // more code internal visibility at link time. (Access to private functions
1227 // is already prohibited by type privacy for function types.)
1228 fn visit_qpath(&mut self, qpath: &'tcx hir::QPath<'tcx>, id: hir::HirId, span: Span) {
1229 let def = match qpath {
1230 hir::QPath::Resolved(_, path) => match path.res {
1231 Res::Def(kind, def_id) => Some((kind, def_id)),
1234 hir::QPath::TypeRelative(..) | hir::QPath::LangItem(..) => self
1235 .maybe_typeck_results
1236 .and_then(|typeck_results| typeck_results.type_dependent_def(id)),
1238 let def = def.filter(|(kind, _)| {
1241 DefKind::AssocFn | DefKind::AssocConst | DefKind::AssocTy | DefKind::Static(_)
1244 if let Some((kind, def_id)) = def {
1245 let is_local_static =
1246 if let DefKind::Static(_) = kind { def_id.is_local() } else { false };
1247 if !self.item_is_accessible(def_id) && !is_local_static {
1248 let sess = self.tcx.sess;
1249 let sm = sess.source_map();
1250 let name = match qpath {
1251 hir::QPath::Resolved(..) | hir::QPath::LangItem(..) => {
1252 sm.span_to_snippet(qpath.span()).ok()
1254 hir::QPath::TypeRelative(_, segment) => Some(segment.ident.to_string()),
1256 let kind = kind.descr(def_id);
1257 let _ = match name {
1258 Some(name) => sess.emit_err(ItemIsPrivate { span, kind, descr: name }),
1259 None => sess.emit_err(UnnamedItemIsPrivate { span, kind }),
1265 intravisit::walk_qpath(self, qpath, id, span);
1268 // Check types of patterns.
1269 fn visit_pat(&mut self, pattern: &'tcx hir::Pat<'tcx>) {
1270 if self.check_expr_pat_type(pattern.hir_id, pattern.span) {
1271 // Do not check nested patterns if the error already happened.
1275 intravisit::walk_pat(self, pattern);
1278 fn visit_local(&mut self, local: &'tcx hir::Local<'tcx>) {
1279 if let Some(init) = local.init {
1280 if self.check_expr_pat_type(init.hir_id, init.span) {
1281 // Do not report duplicate errors for `let x = y`.
1286 intravisit::walk_local(self, local);
1289 // Check types in item interfaces.
1290 fn visit_item(&mut self, item: &'tcx hir::Item<'tcx>) {
1291 let orig_current_item = mem::replace(&mut self.current_item, item.def_id);
1292 let old_maybe_typeck_results = self.maybe_typeck_results.take();
1293 intravisit::walk_item(self, item);
1294 self.maybe_typeck_results = old_maybe_typeck_results;
1295 self.current_item = orig_current_item;
1299 impl<'tcx> DefIdVisitor<'tcx> for TypePrivacyVisitor<'tcx> {
1300 fn tcx(&self) -> TyCtxt<'tcx> {
1307 descr: &dyn fmt::Display,
1308 ) -> ControlFlow<Self::BreakTy> {
1309 if self.check_def_id(def_id, kind, descr) {
1312 ControlFlow::CONTINUE
1317 ///////////////////////////////////////////////////////////////////////////////
1318 /// Obsolete visitors for checking for private items in public interfaces.
1319 /// These visitors are supposed to be kept in frozen state and produce an
1320 /// "old error node set". For backward compatibility the new visitor reports
1321 /// warnings instead of hard errors when the erroneous node is not in this old set.
1322 ///////////////////////////////////////////////////////////////////////////////
1324 struct ObsoleteVisiblePrivateTypesVisitor<'a, 'tcx> {
1326 access_levels: &'a AccessLevels,
1328 // Set of errors produced by this obsolete visitor.
1329 old_error_set: HirIdSet,
1332 struct ObsoleteCheckTypeForPrivatenessVisitor<'a, 'b, 'tcx> {
1333 inner: &'a ObsoleteVisiblePrivateTypesVisitor<'b, 'tcx>,
1334 /// Whether the type refers to private types.
1335 contains_private: bool,
1336 /// Whether we've recurred at all (i.e., if we're pointing at the
1337 /// first type on which `visit_ty` was called).
1338 at_outer_type: bool,
1339 /// Whether that first type is a public path.
1340 outer_type_is_public_path: bool,
1343 impl<'a, 'tcx> ObsoleteVisiblePrivateTypesVisitor<'a, 'tcx> {
1344 fn path_is_private_type(&self, path: &hir::Path<'_>) -> bool {
1345 let did = match path.res {
1346 Res::PrimTy(..) | Res::SelfTy { .. } | Res::Err => return false,
1347 res => res.def_id(),
1350 // A path can only be private if:
1351 // it's in this crate...
1352 if let Some(did) = did.as_local() {
1353 // .. and it corresponds to a private type in the AST (this returns
1354 // `None` for type parameters).
1355 match self.tcx.hir().find(self.tcx.hir().local_def_id_to_hir_id(did)) {
1356 Some(Node::Item(_)) => !self.tcx.visibility(did).is_public(),
1357 Some(_) | None => false,
1364 fn trait_is_public(&self, trait_id: LocalDefId) -> bool {
1365 // FIXME: this would preferably be using `exported_items`, but all
1366 // traits are exported currently (see `EmbargoVisitor.exported_trait`).
1367 self.access_levels.is_public(trait_id)
1370 fn check_generic_bound(&mut self, bound: &hir::GenericBound<'_>) {
1371 if let hir::GenericBound::Trait(ref trait_ref, _) = *bound {
1372 if self.path_is_private_type(trait_ref.trait_ref.path) {
1373 self.old_error_set.insert(trait_ref.trait_ref.hir_ref_id);
1378 fn item_is_public(&self, def_id: LocalDefId) -> bool {
1379 self.access_levels.is_reachable(def_id) || self.tcx.visibility(def_id).is_public()
1383 impl<'a, 'b, 'tcx, 'v> Visitor<'v> for ObsoleteCheckTypeForPrivatenessVisitor<'a, 'b, 'tcx> {
1384 fn visit_generic_arg(&mut self, generic_arg: &'v hir::GenericArg<'v>) {
1386 hir::GenericArg::Type(t) => self.visit_ty(t),
1387 hir::GenericArg::Infer(inf) => self.visit_ty(&inf.to_ty()),
1388 hir::GenericArg::Lifetime(_) | hir::GenericArg::Const(_) => {}
1392 fn visit_ty(&mut self, ty: &hir::Ty<'_>) {
1393 if let hir::TyKind::Path(hir::QPath::Resolved(_, path)) = ty.kind {
1394 if self.inner.path_is_private_type(path) {
1395 self.contains_private = true;
1396 // Found what we're looking for, so let's stop working.
1400 if let hir::TyKind::Path(_) = ty.kind {
1401 if self.at_outer_type {
1402 self.outer_type_is_public_path = true;
1405 self.at_outer_type = false;
1406 intravisit::walk_ty(self, ty)
1409 // Don't want to recurse into `[, .. expr]`.
1410 fn visit_expr(&mut self, _: &hir::Expr<'_>) {}
1413 impl<'a, 'tcx> Visitor<'tcx> for ObsoleteVisiblePrivateTypesVisitor<'a, 'tcx> {
1414 type NestedFilter = nested_filter::All;
1416 /// We want to visit items in the context of their containing
1417 /// module and so forth, so supply a crate for doing a deep walk.
1418 fn nested_visit_map(&mut self) -> Self::Map {
1422 fn visit_item(&mut self, item: &'tcx hir::Item<'tcx>) {
1424 // Contents of a private mod can be re-exported, so we need
1425 // to check internals.
1426 hir::ItemKind::Mod(_) => {}
1428 // An `extern {}` doesn't introduce a new privacy
1429 // namespace (the contents have their own privacies).
1430 hir::ItemKind::ForeignMod { .. } => {}
1432 hir::ItemKind::Trait(.., bounds, _) => {
1433 if !self.trait_is_public(item.def_id) {
1437 for bound in bounds.iter() {
1438 self.check_generic_bound(bound)
1442 // Impls need some special handling to try to offer useful
1443 // error messages without (too many) false positives
1444 // (i.e., we could just return here to not check them at
1445 // all, or some worse estimation of whether an impl is
1446 // publicly visible).
1447 hir::ItemKind::Impl(ref impl_) => {
1448 // `impl [... for] Private` is never visible.
1449 let self_contains_private;
1450 // `impl [... for] Public<...>`, but not `impl [... for]
1451 // Vec<Public>` or `(Public,)`, etc.
1452 let self_is_public_path;
1454 // Check the properties of the `Self` type:
1456 let mut visitor = ObsoleteCheckTypeForPrivatenessVisitor {
1458 contains_private: false,
1459 at_outer_type: true,
1460 outer_type_is_public_path: false,
1462 visitor.visit_ty(impl_.self_ty);
1463 self_contains_private = visitor.contains_private;
1464 self_is_public_path = visitor.outer_type_is_public_path;
1467 // Miscellaneous info about the impl:
1469 // `true` iff this is `impl Private for ...`.
1470 let not_private_trait = impl_.of_trait.as_ref().map_or(
1471 true, // no trait counts as public trait
1473 if let Some(def_id) = tr.path.res.def_id().as_local() {
1474 self.trait_is_public(def_id)
1476 true // external traits must be public
1481 // `true` iff this is a trait impl or at least one method is public.
1483 // `impl Public { $( fn ...() {} )* }` is not visible.
1485 // This is required over just using the methods' privacy
1486 // directly because we might have `impl<T: Foo<Private>> ...`,
1487 // and we shouldn't warn about the generics if all the methods
1488 // are private (because `T` won't be visible externally).
1489 let trait_or_some_public_method = impl_.of_trait.is_some()
1490 || impl_.items.iter().any(|impl_item_ref| {
1491 let impl_item = self.tcx.hir().impl_item(impl_item_ref.id);
1492 match impl_item.kind {
1493 hir::ImplItemKind::Const(..) | hir::ImplItemKind::Fn(..) => {
1494 self.access_levels.is_reachable(impl_item_ref.id.def_id)
1496 hir::ImplItemKind::TyAlias(_) => false,
1500 if !self_contains_private && not_private_trait && trait_or_some_public_method {
1501 intravisit::walk_generics(self, &impl_.generics);
1503 match impl_.of_trait {
1505 for impl_item_ref in impl_.items {
1506 // This is where we choose whether to walk down
1507 // further into the impl to check its items. We
1508 // should only walk into public items so that we
1509 // don't erroneously report errors for private
1510 // types in private items.
1511 let impl_item = self.tcx.hir().impl_item(impl_item_ref.id);
1512 match impl_item.kind {
1513 hir::ImplItemKind::Const(..) | hir::ImplItemKind::Fn(..)
1514 if self.item_is_public(impl_item.def_id) =>
1516 intravisit::walk_impl_item(self, impl_item)
1518 hir::ImplItemKind::TyAlias(..) => {
1519 intravisit::walk_impl_item(self, impl_item)
1526 // Any private types in a trait impl fall into three
1528 // 1. mentioned in the trait definition
1529 // 2. mentioned in the type params/generics
1530 // 3. mentioned in the associated types of the impl
1532 // Those in 1. can only occur if the trait is in
1533 // this crate and will have been warned about on the
1534 // trait definition (there's no need to warn twice
1535 // so we don't check the methods).
1537 // Those in 2. are warned via walk_generics and this
1539 intravisit::walk_path(self, tr.path);
1541 // Those in 3. are warned with this call.
1542 for impl_item_ref in impl_.items {
1543 let impl_item = self.tcx.hir().impl_item(impl_item_ref.id);
1544 if let hir::ImplItemKind::TyAlias(ty) = impl_item.kind {
1550 } else if impl_.of_trait.is_none() && self_is_public_path {
1551 // `impl Public<Private> { ... }`. Any public static
1552 // methods will be visible as `Public::foo`.
1553 let mut found_pub_static = false;
1554 for impl_item_ref in impl_.items {
1555 if self.access_levels.is_reachable(impl_item_ref.id.def_id)
1556 || self.tcx.visibility(impl_item_ref.id.def_id)
1557 == ty::Visibility::Public
1559 let impl_item = self.tcx.hir().impl_item(impl_item_ref.id);
1560 match impl_item_ref.kind {
1561 AssocItemKind::Const => {
1562 found_pub_static = true;
1563 intravisit::walk_impl_item(self, impl_item);
1565 AssocItemKind::Fn { has_self: false } => {
1566 found_pub_static = true;
1567 intravisit::walk_impl_item(self, impl_item);
1573 if found_pub_static {
1574 intravisit::walk_generics(self, &impl_.generics)
1580 // `type ... = ...;` can contain private types, because
1581 // we're introducing a new name.
1582 hir::ItemKind::TyAlias(..) => return,
1584 // Not at all public, so we don't care.
1585 _ if !self.item_is_public(item.def_id) => {
1592 // We've carefully constructed it so that if we're here, then
1593 // any `visit_ty`'s will be called on things that are in
1594 // public signatures, i.e., things that we're interested in for
1596 intravisit::walk_item(self, item);
1599 fn visit_generics(&mut self, generics: &'tcx hir::Generics<'tcx>) {
1600 for predicate in generics.predicates {
1602 hir::WherePredicate::BoundPredicate(bound_pred) => {
1603 for bound in bound_pred.bounds.iter() {
1604 self.check_generic_bound(bound)
1607 hir::WherePredicate::RegionPredicate(_) => {}
1608 hir::WherePredicate::EqPredicate(eq_pred) => {
1609 self.visit_ty(eq_pred.rhs_ty);
1615 fn visit_foreign_item(&mut self, item: &'tcx hir::ForeignItem<'tcx>) {
1616 if self.access_levels.is_reachable(item.def_id) {
1617 intravisit::walk_foreign_item(self, item)
1621 fn visit_ty(&mut self, t: &'tcx hir::Ty<'tcx>) {
1622 if let hir::TyKind::Path(hir::QPath::Resolved(_, path)) = t.kind {
1623 if self.path_is_private_type(path) {
1624 self.old_error_set.insert(t.hir_id);
1627 intravisit::walk_ty(self, t)
1632 v: &'tcx hir::Variant<'tcx>,
1633 g: &'tcx hir::Generics<'tcx>,
1634 item_id: hir::HirId,
1636 if self.access_levels.is_reachable(self.tcx.hir().local_def_id(v.id)) {
1637 self.in_variant = true;
1638 intravisit::walk_variant(self, v, g, item_id);
1639 self.in_variant = false;
1643 fn visit_field_def(&mut self, s: &'tcx hir::FieldDef<'tcx>) {
1644 let def_id = self.tcx.hir().local_def_id(s.hir_id);
1645 let vis = self.tcx.visibility(def_id);
1646 if vis.is_public() || self.in_variant {
1647 intravisit::walk_field_def(self, s);
1651 // We don't need to introspect into these at all: an
1652 // expression/block context can't possibly contain exported things.
1653 // (Making them no-ops stops us from traversing the whole AST without
1654 // having to be super careful about our `walk_...` calls above.)
1655 fn visit_block(&mut self, _: &'tcx hir::Block<'tcx>) {}
1656 fn visit_expr(&mut self, _: &'tcx hir::Expr<'tcx>) {}
1659 ///////////////////////////////////////////////////////////////////////////////
1660 /// SearchInterfaceForPrivateItemsVisitor traverses an item's interface and
1661 /// finds any private components in it.
1662 /// PrivateItemsInPublicInterfacesVisitor ensures there are no private types
1663 /// and traits in public interfaces.
1664 ///////////////////////////////////////////////////////////////////////////////
1666 struct SearchInterfaceForPrivateItemsVisitor<'tcx> {
1668 item_def_id: LocalDefId,
1669 /// The visitor checks that each component type is at least this visible.
1670 required_visibility: ty::Visibility,
1671 has_old_errors: bool,
1675 impl SearchInterfaceForPrivateItemsVisitor<'_> {
1676 fn generics(&mut self) -> &mut Self {
1677 for param in &self.tcx.generics_of(self.item_def_id).params {
1679 GenericParamDefKind::Lifetime => {}
1680 GenericParamDefKind::Type { has_default, .. } => {
1682 self.visit(self.tcx.type_of(param.def_id));
1685 // FIXME(generic_const_exprs): May want to look inside const here
1686 GenericParamDefKind::Const { .. } => {
1687 self.visit(self.tcx.type_of(param.def_id));
1694 fn predicates(&mut self) -> &mut Self {
1695 // N.B., we use `explicit_predicates_of` and not `predicates_of`
1696 // because we don't want to report privacy errors due to where
1697 // clauses that the compiler inferred. We only want to
1698 // consider the ones that the user wrote. This is important
1699 // for the inferred outlives rules; see
1700 // `src/test/ui/rfc-2093-infer-outlives/privacy.rs`.
1701 self.visit_predicates(self.tcx.explicit_predicates_of(self.item_def_id));
1705 fn bounds(&mut self) -> &mut Self {
1706 self.visit_predicates(ty::GenericPredicates {
1708 predicates: self.tcx.explicit_item_bounds(self.item_def_id),
1713 fn ty(&mut self) -> &mut Self {
1714 self.visit(self.tcx.type_of(self.item_def_id));
1718 fn check_def_id(&mut self, def_id: DefId, kind: &str, descr: &dyn fmt::Display) -> bool {
1719 if self.leaks_private_dep(def_id) {
1720 self.tcx.struct_span_lint_hir(
1721 lint::builtin::EXPORTED_PRIVATE_DEPENDENCIES,
1722 self.tcx.hir().local_def_id_to_hir_id(self.item_def_id),
1723 self.tcx.def_span(self.item_def_id.to_def_id()),
1725 lint.build(&format!(
1726 "{} `{}` from private dependency '{}' in public \
1730 self.tcx.crate_name(def_id.krate)
1737 let hir_id = match def_id.as_local() {
1738 Some(def_id) => self.tcx.hir().local_def_id_to_hir_id(def_id),
1739 None => return false,
1742 let vis = self.tcx.visibility(def_id);
1743 if !vis.is_at_least(self.required_visibility, self.tcx) {
1744 let vis_descr = match vis {
1745 ty::Visibility::Public => "public",
1746 ty::Visibility::Invisible => "private",
1747 ty::Visibility::Restricted(vis_def_id) => {
1748 if vis_def_id == self.tcx.parent_module(hir_id).to_def_id() {
1750 } else if vis_def_id.is_top_level_module() {
1757 let span = self.tcx.def_span(self.item_def_id.to_def_id());
1758 if self.has_old_errors
1760 || self.tcx.resolutions(()).has_pub_restricted
1762 let descr = descr.to_string();
1764 self.tcx.sess.source_map().guess_head_span(self.tcx.def_span(def_id));
1765 if kind == "trait" {
1766 self.tcx.sess.emit_err(InPublicInterfaceTraits {
1774 self.tcx.sess.emit_err(InPublicInterface {
1783 let err_code = if kind == "trait" { "E0445" } else { "E0446" };
1784 self.tcx.struct_span_lint_hir(
1785 lint::builtin::PRIVATE_IN_PUBLIC,
1789 lint.build(&format!(
1791 format!("{} {} `{}` in public interface", vis_descr, kind, descr),
1803 /// An item is 'leaked' from a private dependency if all
1804 /// of the following are true:
1805 /// 1. It's contained within a public type
1806 /// 2. It comes from a private crate
1807 fn leaks_private_dep(&self, item_id: DefId) -> bool {
1808 let ret = self.required_visibility.is_public() && self.tcx.is_private_dep(item_id.krate);
1810 tracing::debug!("leaks_private_dep(item_id={:?})={}", item_id, ret);
1815 impl<'tcx> DefIdVisitor<'tcx> for SearchInterfaceForPrivateItemsVisitor<'tcx> {
1816 fn tcx(&self) -> TyCtxt<'tcx> {
1823 descr: &dyn fmt::Display,
1824 ) -> ControlFlow<Self::BreakTy> {
1825 if self.check_def_id(def_id, kind, descr) {
1828 ControlFlow::CONTINUE
1833 struct PrivateItemsInPublicInterfacesChecker<'tcx> {
1835 old_error_set_ancestry: LocalDefIdSet,
1838 impl<'tcx> PrivateItemsInPublicInterfacesChecker<'tcx> {
1842 required_visibility: ty::Visibility,
1843 ) -> SearchInterfaceForPrivateItemsVisitor<'tcx> {
1844 SearchInterfaceForPrivateItemsVisitor {
1846 item_def_id: def_id,
1847 required_visibility,
1848 has_old_errors: self.old_error_set_ancestry.contains(&def_id),
1853 fn check_assoc_item(
1856 assoc_item_kind: AssocItemKind,
1857 defaultness: hir::Defaultness,
1858 vis: ty::Visibility,
1860 let mut check = self.check(def_id, vis);
1862 let (check_ty, is_assoc_ty) = match assoc_item_kind {
1863 AssocItemKind::Const | AssocItemKind::Fn { .. } => (true, false),
1864 AssocItemKind::Type => (defaultness.has_value(), true),
1866 check.in_assoc_ty = is_assoc_ty;
1867 check.generics().predicates();
1873 pub fn check_item(&mut self, id: ItemId) {
1875 let item_visibility = tcx.visibility(id.def_id);
1876 let def_kind = tcx.def_kind(id.def_id);
1879 DefKind::Const | DefKind::Static(_) | DefKind::Fn | DefKind::TyAlias => {
1880 self.check(id.def_id, item_visibility).generics().predicates().ty();
1882 DefKind::OpaqueTy => {
1883 // `ty()` for opaque types is the underlying type,
1884 // it's not a part of interface, so we skip it.
1885 self.check(id.def_id, item_visibility).generics().bounds();
1888 let item = tcx.hir().item(id);
1889 if let hir::ItemKind::Trait(.., trait_item_refs) = item.kind {
1890 self.check(item.def_id, item_visibility).generics().predicates();
1892 for trait_item_ref in trait_item_refs {
1893 self.check_assoc_item(
1894 trait_item_ref.id.def_id,
1895 trait_item_ref.kind,
1896 trait_item_ref.defaultness,
1900 if let AssocItemKind::Type = trait_item_ref.kind {
1901 self.check(trait_item_ref.id.def_id, item_visibility).bounds();
1906 DefKind::TraitAlias => {
1907 self.check(id.def_id, item_visibility).generics().predicates();
1910 let item = tcx.hir().item(id);
1911 if let hir::ItemKind::Enum(ref def, _) = item.kind {
1912 self.check(item.def_id, item_visibility).generics().predicates();
1914 for variant in def.variants {
1915 for field in variant.data.fields() {
1916 self.check(self.tcx.hir().local_def_id(field.hir_id), item_visibility)
1922 // Subitems of foreign modules have their own publicity.
1923 DefKind::ForeignMod => {
1924 let item = tcx.hir().item(id);
1925 if let hir::ItemKind::ForeignMod { items, .. } = item.kind {
1926 for foreign_item in items {
1927 let vis = tcx.visibility(foreign_item.id.def_id);
1928 self.check(foreign_item.id.def_id, vis).generics().predicates().ty();
1932 // Subitems of structs and unions have their own publicity.
1933 DefKind::Struct | DefKind::Union => {
1934 let item = tcx.hir().item(id);
1935 if let hir::ItemKind::Struct(ref struct_def, _)
1936 | hir::ItemKind::Union(ref struct_def, _) = item.kind
1938 self.check(item.def_id, item_visibility).generics().predicates();
1940 for field in struct_def.fields() {
1941 let def_id = tcx.hir().local_def_id(field.hir_id);
1942 let field_visibility = tcx.visibility(def_id);
1943 self.check(def_id, min(item_visibility, field_visibility, tcx)).ty();
1947 // An inherent impl is public when its type is public
1948 // Subitems of inherent impls have their own publicity.
1949 // A trait impl is public when both its type and its trait are public
1950 // Subitems of trait impls have inherited publicity.
1952 let item = tcx.hir().item(id);
1953 if let hir::ItemKind::Impl(ref impl_) = item.kind {
1954 let impl_vis = ty::Visibility::of_impl(item.def_id, tcx, &Default::default());
1955 // check that private components do not appear in the generics or predicates of inherent impls
1956 // this check is intentionally NOT performed for impls of traits, per #90586
1957 if impl_.of_trait.is_none() {
1958 self.check(item.def_id, impl_vis).generics().predicates();
1960 for impl_item_ref in impl_.items {
1961 let impl_item_vis = if impl_.of_trait.is_none() {
1962 min(tcx.visibility(impl_item_ref.id.def_id), impl_vis, tcx)
1966 self.check_assoc_item(
1967 impl_item_ref.id.def_id,
1969 impl_item_ref.defaultness,
1980 pub fn provide(providers: &mut Providers) {
1981 *providers = Providers {
1983 privacy_access_levels,
1984 check_private_in_public,
1990 fn visibility(tcx: TyCtxt<'_>, def_id: DefId) -> ty::Visibility {
1991 let def_id = def_id.expect_local();
1992 match tcx.resolutions(()).visibilities.get(&def_id) {
1995 let hir_id = tcx.hir().local_def_id_to_hir_id(def_id);
1996 match tcx.hir().get(hir_id) {
1997 // Unique types created for closures participate in type privacy checking.
1998 // They have visibilities inherited from the module they are defined in.
1999 Node::Expr(hir::Expr { kind: hir::ExprKind::Closure{..}, .. })
2000 // - AST lowering creates dummy `use` items which don't
2001 // get their entries in the resolver's visibility table.
2002 // - AST lowering also creates opaque type items with inherited visibilities.
2003 // Visibility on them should have no effect, but to avoid the visibility
2004 // query failing on some items, we provide it for opaque types as well.
2005 | Node::Item(hir::Item {
2006 kind: hir::ItemKind::Use(_, hir::UseKind::ListStem) | hir::ItemKind::OpaqueTy(..),
2008 }) => ty::Visibility::Restricted(tcx.parent_module(hir_id).to_def_id()),
2009 // Visibilities of trait impl items are inherited from their traits
2010 // and are not filled in resolve.
2011 Node::ImplItem(impl_item) => {
2012 match tcx.hir().get_by_def_id(tcx.hir().get_parent_item(hir_id)) {
2013 Node::Item(hir::Item {
2014 kind: hir::ItemKind::Impl(hir::Impl { of_trait: Some(tr), .. }),
2016 }) => tr.path.res.opt_def_id().map_or_else(
2018 tcx.sess.delay_span_bug(tr.path.span, "trait without a def-id");
2019 ty::Visibility::Public
2021 |def_id| tcx.visibility(def_id),
2023 _ => span_bug!(impl_item.span, "the parent is not a trait impl"),
2027 tcx.def_span(def_id),
2028 "visibility table unexpectedly missing a def-id: {:?}",
2036 fn check_mod_privacy(tcx: TyCtxt<'_>, module_def_id: LocalDefId) {
2037 // Check privacy of names not checked in previous compilation stages.
2039 NamePrivacyVisitor { tcx, maybe_typeck_results: None, current_item: module_def_id };
2040 let (module, span, hir_id) = tcx.hir().get_module(module_def_id);
2042 intravisit::walk_mod(&mut visitor, module, hir_id);
2044 // Check privacy of explicitly written types and traits as well as
2045 // inferred types of expressions and patterns.
2047 TypePrivacyVisitor { tcx, maybe_typeck_results: None, current_item: module_def_id, span };
2048 intravisit::walk_mod(&mut visitor, module, hir_id);
2051 fn privacy_access_levels(tcx: TyCtxt<'_>, (): ()) -> &AccessLevels {
2052 // Build up a set of all exported items in the AST. This is a set of all
2053 // items which are reachable from external crates based on visibility.
2054 let mut visitor = EmbargoVisitor {
2056 access_levels: tcx.resolutions(()).access_levels.clone(),
2057 macro_reachable: Default::default(),
2058 prev_level: Some(AccessLevel::Public),
2063 tcx.hir().walk_toplevel_module(&mut visitor);
2064 if visitor.changed {
2065 visitor.changed = false;
2071 tcx.arena.alloc(visitor.access_levels)
2074 fn check_private_in_public(tcx: TyCtxt<'_>, (): ()) {
2075 let access_levels = tcx.privacy_access_levels(());
2077 let mut visitor = ObsoleteVisiblePrivateTypesVisitor {
2081 old_error_set: Default::default(),
2083 tcx.hir().walk_toplevel_module(&mut visitor);
2085 let mut old_error_set_ancestry = HirIdSet::default();
2086 for mut id in visitor.old_error_set.iter().copied() {
2088 if !old_error_set_ancestry.insert(id) {
2091 let parent = tcx.hir().get_parent_node(id);
2099 // Check for private types and traits in public interfaces.
2100 let mut checker = PrivateItemsInPublicInterfacesChecker {
2102 // Only definition IDs are ever searched in `old_error_set_ancestry`,
2103 // so we can filter away all non-definition IDs at this point.
2104 old_error_set_ancestry: old_error_set_ancestry
2106 .filter_map(|hir_id| tcx.hir().opt_local_def_id(hir_id))
2110 for id in tcx.hir().items() {
2111 checker.check_item(id);