| // Copyright 2014 The Rust Project Developers. See the COPYRIGHT |
| // file at the top-level directory of this distribution and at |
| // http://rust-lang.org/COPYRIGHT. |
| // |
| // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or |
| // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license |
| // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your |
| // option. This file may not be copied, modified, or distributed |
| // except according to those terms. |
| |
| //! A pass that annotates every item and method with its stability level, |
| //! propagating default levels lexically from parent to children ast nodes. |
| |
| pub use self::StabilityLevel::*; |
| |
| use lint; |
| use hir::def::Def; |
| use hir::def_id::{CrateNum, CRATE_DEF_INDEX, DefId, LOCAL_CRATE}; |
| use ty::{self, TyCtxt}; |
| use middle::privacy::AccessLevels; |
| use session::DiagnosticMessageId; |
| use syntax::symbol::Symbol; |
| use syntax_pos::{Span, MultiSpan, DUMMY_SP}; |
| use syntax::ast; |
| use syntax::ast::{NodeId, Attribute}; |
| use syntax::feature_gate::{GateIssue, emit_feature_err, find_lang_feature_accepted_version}; |
| use syntax::attr::{self, Stability, Deprecation}; |
| use util::nodemap::{FxHashSet, FxHashMap}; |
| |
| use hir; |
| use hir::{Item, Generics, StructField, Variant, HirId}; |
| use hir::intravisit::{self, Visitor, NestedVisitorMap}; |
| |
| use std::mem::replace; |
| use std::cmp::Ordering; |
| |
| #[derive(RustcEncodable, RustcDecodable, PartialEq, PartialOrd, Clone, Copy, Debug, Eq, Hash)] |
| pub enum StabilityLevel { |
| Unstable, |
| Stable, |
| } |
| |
| impl StabilityLevel { |
| pub fn from_attr_level(level: &attr::StabilityLevel) -> Self { |
| if level.is_stable() { Stable } else { Unstable } |
| } |
| } |
| |
| #[derive(PartialEq)] |
| enum AnnotationKind { |
| // Annotation is required if not inherited from unstable parents |
| Required, |
| // Annotation is useless, reject it |
| Prohibited, |
| // Annotation itself is useless, but it can be propagated to children |
| Container, |
| } |
| |
| /// An entry in the `depr_map`. |
| #[derive(Clone)] |
| pub struct DeprecationEntry { |
| /// The metadata of the attribute associated with this entry. |
| pub attr: Deprecation, |
| /// The def id where the attr was originally attached. `None` for non-local |
| /// `DefId`'s. |
| origin: Option<HirId>, |
| } |
| |
| impl_stable_hash_for!(struct self::DeprecationEntry { |
| attr, |
| origin |
| }); |
| |
| impl DeprecationEntry { |
| fn local(attr: Deprecation, id: HirId) -> DeprecationEntry { |
| DeprecationEntry { |
| attr, |
| origin: Some(id), |
| } |
| } |
| |
| pub fn external(attr: Deprecation) -> DeprecationEntry { |
| DeprecationEntry { |
| attr, |
| origin: None, |
| } |
| } |
| |
| pub fn same_origin(&self, other: &DeprecationEntry) -> bool { |
| match (self.origin, other.origin) { |
| (Some(o1), Some(o2)) => o1 == o2, |
| _ => false |
| } |
| } |
| } |
| |
| /// A stability index, giving the stability level for items and methods. |
| pub struct Index<'tcx> { |
| /// This is mostly a cache, except the stabilities of local items |
| /// are filled by the annotator. |
| stab_map: FxHashMap<HirId, &'tcx Stability>, |
| depr_map: FxHashMap<HirId, DeprecationEntry>, |
| |
| /// Maps for each crate whether it is part of the staged API. |
| staged_api: FxHashMap<CrateNum, bool>, |
| |
| /// Features enabled for this crate. |
| active_features: FxHashSet<Symbol>, |
| } |
| |
| impl_stable_hash_for!(struct self::Index<'tcx> { |
| stab_map, |
| depr_map, |
| staged_api, |
| active_features |
| }); |
| |
| // A private tree-walker for producing an Index. |
| struct Annotator<'a, 'tcx: 'a> { |
| tcx: TyCtxt<'a, 'tcx, 'tcx>, |
| index: &'a mut Index<'tcx>, |
| parent_stab: Option<&'tcx Stability>, |
| parent_depr: Option<DeprecationEntry>, |
| in_trait_impl: bool, |
| } |
| |
| impl<'a, 'tcx: 'a> Annotator<'a, 'tcx> { |
| // Determine the stability for a node based on its attributes and inherited |
| // stability. The stability is recorded in the index and used as the parent. |
| fn annotate<F>(&mut self, id: NodeId, attrs: &[Attribute], |
| item_sp: Span, kind: AnnotationKind, visit_children: F) |
| where F: FnOnce(&mut Self) |
| { |
| if self.tcx.sess.features.borrow().staged_api { |
| // This crate explicitly wants staged API. |
| debug!("annotate(id = {:?}, attrs = {:?})", id, attrs); |
| if let Some(..) = attr::find_deprecation(self.tcx.sess.diagnostic(), attrs, item_sp) { |
| self.tcx.sess.span_err(item_sp, "`#[deprecated]` cannot be used in staged api, \ |
| use `#[rustc_deprecated]` instead"); |
| } |
| if let Some(mut stab) = attr::find_stability(self.tcx.sess.diagnostic(), |
| attrs, item_sp) { |
| // Error if prohibited, or can't inherit anything from a container |
| if kind == AnnotationKind::Prohibited || |
| (kind == AnnotationKind::Container && |
| stab.level.is_stable() && |
| stab.rustc_depr.is_none()) { |
| self.tcx.sess.span_err(item_sp, "This stability annotation is useless"); |
| } |
| |
| debug!("annotate: found {:?}", stab); |
| // If parent is deprecated and we're not, inherit this by merging |
| // deprecated_since and its reason. |
| if let Some(parent_stab) = self.parent_stab { |
| if parent_stab.rustc_depr.is_some() && stab.rustc_depr.is_none() { |
| stab.rustc_depr = parent_stab.rustc_depr.clone() |
| } |
| } |
| |
| let stab = self.tcx.intern_stability(stab); |
| |
| // Check if deprecated_since < stable_since. If it is, |
| // this is *almost surely* an accident. |
| if let (&Some(attr::RustcDeprecation {since: dep_since, ..}), |
| &attr::Stable {since: stab_since}) = (&stab.rustc_depr, &stab.level) { |
| // Explicit version of iter::order::lt to handle parse errors properly |
| for (dep_v, stab_v) in |
| dep_since.as_str().split(".").zip(stab_since.as_str().split(".")) { |
| if let (Ok(dep_v), Ok(stab_v)) = (dep_v.parse::<u64>(), stab_v.parse()) { |
| match dep_v.cmp(&stab_v) { |
| Ordering::Less => { |
| self.tcx.sess.span_err(item_sp, "An API can't be stabilized \ |
| after it is deprecated"); |
| break |
| } |
| Ordering::Equal => continue, |
| Ordering::Greater => break, |
| } |
| } else { |
| // Act like it isn't less because the question is now nonsensical, |
| // and this makes us not do anything else interesting. |
| self.tcx.sess.span_err(item_sp, "Invalid stability or deprecation \ |
| version found"); |
| break |
| } |
| } |
| } |
| |
| let hir_id = self.tcx.hir.node_to_hir_id(id); |
| self.index.stab_map.insert(hir_id, stab); |
| |
| let orig_parent_stab = replace(&mut self.parent_stab, Some(stab)); |
| visit_children(self); |
| self.parent_stab = orig_parent_stab; |
| } else { |
| debug!("annotate: not found, parent = {:?}", self.parent_stab); |
| if let Some(stab) = self.parent_stab { |
| if stab.level.is_unstable() { |
| let hir_id = self.tcx.hir.node_to_hir_id(id); |
| self.index.stab_map.insert(hir_id, stab); |
| } |
| } |
| visit_children(self); |
| } |
| } else { |
| // Emit errors for non-staged-api crates. |
| for attr in attrs { |
| let tag = unwrap_or!(attr.name(), continue); |
| if tag == "unstable" || tag == "stable" || tag == "rustc_deprecated" { |
| attr::mark_used(attr); |
| self.tcx.sess.span_err(attr.span(), "stability attributes may not be used \ |
| outside of the standard library"); |
| } |
| } |
| |
| // Propagate unstability. This can happen even for non-staged-api crates in case |
| // -Zforce-unstable-if-unmarked is set. |
| if let Some(stab) = self.parent_stab { |
| if stab.level.is_unstable() { |
| let hir_id = self.tcx.hir.node_to_hir_id(id); |
| self.index.stab_map.insert(hir_id, stab); |
| } |
| } |
| |
| if let Some(depr) = attr::find_deprecation(self.tcx.sess.diagnostic(), attrs, item_sp) { |
| if kind == AnnotationKind::Prohibited { |
| self.tcx.sess.span_err(item_sp, "This deprecation annotation is useless"); |
| } |
| |
| // `Deprecation` is just two pointers, no need to intern it |
| let hir_id = self.tcx.hir.node_to_hir_id(id); |
| let depr_entry = DeprecationEntry::local(depr, hir_id); |
| self.index.depr_map.insert(hir_id, depr_entry.clone()); |
| |
| let orig_parent_depr = replace(&mut self.parent_depr, |
| Some(depr_entry)); |
| visit_children(self); |
| self.parent_depr = orig_parent_depr; |
| } else if let Some(parent_depr) = self.parent_depr.clone() { |
| let hir_id = self.tcx.hir.node_to_hir_id(id); |
| self.index.depr_map.insert(hir_id, parent_depr); |
| visit_children(self); |
| } else { |
| visit_children(self); |
| } |
| } |
| } |
| } |
| |
| impl<'a, 'tcx> Visitor<'tcx> for Annotator<'a, 'tcx> { |
| /// Because stability levels are scoped lexically, we want to walk |
| /// nested items in the context of the outer item, so enable |
| /// deep-walking. |
| fn nested_visit_map<'this>(&'this mut self) -> NestedVisitorMap<'this, 'tcx> { |
| NestedVisitorMap::All(&self.tcx.hir) |
| } |
| |
| fn visit_item(&mut self, i: &'tcx Item) { |
| let orig_in_trait_impl = self.in_trait_impl; |
| let mut kind = AnnotationKind::Required; |
| match i.node { |
| // Inherent impls and foreign modules serve only as containers for other items, |
| // they don't have their own stability. They still can be annotated as unstable |
| // and propagate this unstability to children, but this annotation is completely |
| // optional. They inherit stability from their parents when unannotated. |
| hir::ItemImpl(.., None, _, _) | hir::ItemForeignMod(..) => { |
| self.in_trait_impl = false; |
| kind = AnnotationKind::Container; |
| } |
| hir::ItemImpl(.., Some(_), _, _) => { |
| self.in_trait_impl = true; |
| } |
| hir::ItemStruct(ref sd, _) => { |
| if !sd.is_struct() { |
| self.annotate(sd.id(), &i.attrs, i.span, AnnotationKind::Required, |_| {}) |
| } |
| } |
| _ => {} |
| } |
| |
| self.annotate(i.id, &i.attrs, i.span, kind, |v| { |
| intravisit::walk_item(v, i) |
| }); |
| self.in_trait_impl = orig_in_trait_impl; |
| } |
| |
| fn visit_trait_item(&mut self, ti: &'tcx hir::TraitItem) { |
| self.annotate(ti.id, &ti.attrs, ti.span, AnnotationKind::Required, |v| { |
| intravisit::walk_trait_item(v, ti); |
| }); |
| } |
| |
| fn visit_impl_item(&mut self, ii: &'tcx hir::ImplItem) { |
| let kind = if self.in_trait_impl { |
| AnnotationKind::Prohibited |
| } else { |
| AnnotationKind::Required |
| }; |
| self.annotate(ii.id, &ii.attrs, ii.span, kind, |v| { |
| intravisit::walk_impl_item(v, ii); |
| }); |
| } |
| |
| fn visit_variant(&mut self, var: &'tcx Variant, g: &'tcx Generics, item_id: NodeId) { |
| self.annotate(var.node.data.id(), &var.node.attrs, var.span, AnnotationKind::Required, |v| { |
| intravisit::walk_variant(v, var, g, item_id); |
| }) |
| } |
| |
| fn visit_struct_field(&mut self, s: &'tcx StructField) { |
| self.annotate(s.id, &s.attrs, s.span, AnnotationKind::Required, |v| { |
| intravisit::walk_struct_field(v, s); |
| }); |
| } |
| |
| fn visit_foreign_item(&mut self, i: &'tcx hir::ForeignItem) { |
| self.annotate(i.id, &i.attrs, i.span, AnnotationKind::Required, |v| { |
| intravisit::walk_foreign_item(v, i); |
| }); |
| } |
| |
| fn visit_macro_def(&mut self, md: &'tcx hir::MacroDef) { |
| self.annotate(md.id, &md.attrs, md.span, AnnotationKind::Required, |_| {}); |
| } |
| } |
| |
| struct MissingStabilityAnnotations<'a, 'tcx: 'a> { |
| tcx: TyCtxt<'a, 'tcx, 'tcx>, |
| access_levels: &'a AccessLevels, |
| } |
| |
| impl<'a, 'tcx: 'a> MissingStabilityAnnotations<'a, 'tcx> { |
| fn check_missing_stability(&self, id: NodeId, span: Span) { |
| let hir_id = self.tcx.hir.node_to_hir_id(id); |
| let stab = self.tcx.stability().local_stability(hir_id); |
| let is_error = !self.tcx.sess.opts.test && |
| stab.is_none() && |
| self.access_levels.is_reachable(id); |
| if is_error { |
| self.tcx.sess.span_err(span, "This node does not have a stability attribute"); |
| } |
| } |
| } |
| |
| impl<'a, 'tcx> Visitor<'tcx> for MissingStabilityAnnotations<'a, 'tcx> { |
| fn nested_visit_map<'this>(&'this mut self) -> NestedVisitorMap<'this, 'tcx> { |
| NestedVisitorMap::OnlyBodies(&self.tcx.hir) |
| } |
| |
| fn visit_item(&mut self, i: &'tcx Item) { |
| match i.node { |
| // Inherent impls and foreign modules serve only as containers for other items, |
| // they don't have their own stability. They still can be annotated as unstable |
| // and propagate this unstability to children, but this annotation is completely |
| // optional. They inherit stability from their parents when unannotated. |
| hir::ItemImpl(.., None, _, _) | hir::ItemForeignMod(..) => {} |
| |
| _ => self.check_missing_stability(i.id, i.span) |
| } |
| |
| intravisit::walk_item(self, i) |
| } |
| |
| fn visit_trait_item(&mut self, ti: &'tcx hir::TraitItem) { |
| self.check_missing_stability(ti.id, ti.span); |
| intravisit::walk_trait_item(self, ti); |
| } |
| |
| fn visit_impl_item(&mut self, ii: &'tcx hir::ImplItem) { |
| let impl_def_id = self.tcx.hir.local_def_id(self.tcx.hir.get_parent(ii.id)); |
| if self.tcx.impl_trait_ref(impl_def_id).is_none() { |
| self.check_missing_stability(ii.id, ii.span); |
| } |
| intravisit::walk_impl_item(self, ii); |
| } |
| |
| fn visit_variant(&mut self, var: &'tcx Variant, g: &'tcx Generics, item_id: NodeId) { |
| self.check_missing_stability(var.node.data.id(), var.span); |
| intravisit::walk_variant(self, var, g, item_id); |
| } |
| |
| fn visit_struct_field(&mut self, s: &'tcx StructField) { |
| self.check_missing_stability(s.id, s.span); |
| intravisit::walk_struct_field(self, s); |
| } |
| |
| fn visit_foreign_item(&mut self, i: &'tcx hir::ForeignItem) { |
| self.check_missing_stability(i.id, i.span); |
| intravisit::walk_foreign_item(self, i); |
| } |
| |
| fn visit_macro_def(&mut self, md: &'tcx hir::MacroDef) { |
| self.check_missing_stability(md.id, md.span); |
| } |
| } |
| |
| impl<'a, 'tcx> Index<'tcx> { |
| pub fn new(tcx: TyCtxt<'a, 'tcx, 'tcx>) -> Index<'tcx> { |
| let is_staged_api = |
| tcx.sess.opts.debugging_opts.force_unstable_if_unmarked || |
| tcx.sess.features.borrow().staged_api; |
| let mut staged_api = FxHashMap(); |
| staged_api.insert(LOCAL_CRATE, is_staged_api); |
| let mut index = Index { |
| staged_api, |
| stab_map: FxHashMap(), |
| depr_map: FxHashMap(), |
| active_features: FxHashSet(), |
| }; |
| |
| let ref active_lib_features = tcx.sess.features.borrow().declared_lib_features; |
| |
| // Put the active features into a map for quick lookup |
| index.active_features = active_lib_features.iter().map(|&(ref s, _)| s.clone()).collect(); |
| |
| { |
| let krate = tcx.hir.krate(); |
| let mut annotator = Annotator { |
| tcx, |
| index: &mut index, |
| parent_stab: None, |
| parent_depr: None, |
| in_trait_impl: false, |
| }; |
| |
| // If the `-Z force-unstable-if-unmarked` flag is passed then we provide |
| // a parent stability annotation which indicates that this is private |
| // with the `rustc_private` feature. This is intended for use when |
| // compiling librustc crates themselves so we can leverage crates.io |
| // while maintaining the invariant that all sysroot crates are unstable |
| // by default and are unable to be used. |
| if tcx.sess.opts.debugging_opts.force_unstable_if_unmarked { |
| let reason = "this crate is being loaded from the sysroot, an \ |
| unstable location; did you mean to load this crate \ |
| from crates.io via `Cargo.toml` instead?"; |
| let stability = tcx.intern_stability(Stability { |
| level: attr::StabilityLevel::Unstable { |
| reason: Some(Symbol::intern(reason)), |
| issue: 27812, |
| }, |
| feature: Symbol::intern("rustc_private"), |
| rustc_depr: None, |
| rustc_const_unstable: None, |
| }); |
| annotator.parent_stab = Some(stability); |
| } |
| |
| annotator.annotate(ast::CRATE_NODE_ID, |
| &krate.attrs, |
| krate.span, |
| AnnotationKind::Required, |
| |v| intravisit::walk_crate(v, krate)); |
| } |
| return index |
| } |
| |
| pub fn local_stability(&self, id: HirId) -> Option<&'tcx Stability> { |
| self.stab_map.get(&id).cloned() |
| } |
| |
| pub fn local_deprecation_entry(&self, id: HirId) -> Option<DeprecationEntry> { |
| self.depr_map.get(&id).cloned() |
| } |
| } |
| |
| /// Cross-references the feature names of unstable APIs with enabled |
| /// features and possibly prints errors. |
| pub fn check_unstable_api_usage<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>) { |
| let mut checker = Checker { tcx: tcx }; |
| tcx.hir.krate().visit_all_item_likes(&mut checker.as_deep_visitor()); |
| } |
| |
| struct Checker<'a, 'tcx: 'a> { |
| tcx: TyCtxt<'a, 'tcx, 'tcx>, |
| } |
| |
| impl<'a, 'gcx, 'tcx> TyCtxt<'a, 'gcx, 'tcx> { |
| // (See issue #38412) |
| fn skip_stability_check_due_to_privacy(self, mut def_id: DefId) -> bool { |
| // Check if `def_id` is a trait method. |
| match self.describe_def(def_id) { |
| Some(Def::Method(_)) | |
| Some(Def::AssociatedTy(_)) | |
| Some(Def::AssociatedConst(_)) => { |
| match self.associated_item(def_id).container { |
| ty::TraitContainer(trait_def_id) => { |
| // Trait methods do not declare visibility (even |
| // for visibility info in cstore). Use containing |
| // trait instead, so methods of pub traits are |
| // themselves considered pub. |
| def_id = trait_def_id; |
| } |
| _ => {} |
| } |
| } |
| _ => {} |
| } |
| |
| let visibility = self.visibility(def_id); |
| |
| match visibility { |
| // must check stability for pub items. |
| ty::Visibility::Public => false, |
| |
| // these are not visible outside crate; therefore |
| // stability markers are irrelevant, if even present. |
| ty::Visibility::Restricted(..) | |
| ty::Visibility::Invisible => true, |
| } |
| } |
| |
| pub fn check_stability(self, def_id: DefId, id: NodeId, span: Span) { |
| if span.allows_unstable() { |
| debug!("stability: \ |
| skipping span={:?} since it is internal", span); |
| return; |
| } |
| |
| let lint_deprecated = |def_id: DefId, note: Option<Symbol>| { |
| let path = self.item_path_str(def_id); |
| |
| let msg = if let Some(note) = note { |
| format!("use of deprecated item '{}': {}", path, note) |
| } else { |
| format!("use of deprecated item '{}'", path) |
| }; |
| |
| self.lint_node(lint::builtin::DEPRECATED, id, span, &msg); |
| }; |
| |
| // Deprecated attributes apply in-crate and cross-crate. |
| if let Some(depr_entry) = self.lookup_deprecation_entry(def_id) { |
| let skip = if id == ast::DUMMY_NODE_ID { |
| true |
| } else { |
| let parent_def_id = self.hir.local_def_id(self.hir.get_parent(id)); |
| self.lookup_deprecation_entry(parent_def_id).map_or(false, |parent_depr| { |
| parent_depr.same_origin(&depr_entry) |
| }) |
| }; |
| |
| if !skip { |
| lint_deprecated(def_id, depr_entry.attr.note); |
| } |
| } |
| |
| let is_staged_api = self.lookup_stability(DefId { |
| index: CRATE_DEF_INDEX, |
| ..def_id |
| }).is_some(); |
| if !is_staged_api { |
| return; |
| } |
| |
| let stability = self.lookup_stability(def_id); |
| debug!("stability: \ |
| inspecting def_id={:?} span={:?} of stability={:?}", def_id, span, stability); |
| |
| if let Some(&Stability{rustc_depr: Some(attr::RustcDeprecation { reason, .. }), ..}) |
| = stability { |
| if id != ast::DUMMY_NODE_ID { |
| lint_deprecated(def_id, Some(reason)); |
| } |
| } |
| |
| // Only the cross-crate scenario matters when checking unstable APIs |
| let cross_crate = !def_id.is_local(); |
| if !cross_crate { |
| return |
| } |
| |
| // Issue 38412: private items lack stability markers. |
| if self.skip_stability_check_due_to_privacy(def_id) { |
| return |
| } |
| |
| match stability { |
| Some(&Stability { level: attr::Unstable {ref reason, issue}, ref feature, .. }) => { |
| if self.stability().active_features.contains(feature) { |
| return |
| } |
| |
| // When we're compiling the compiler itself we may pull in |
| // crates from crates.io, but those crates may depend on other |
| // crates also pulled in from crates.io. We want to ideally be |
| // able to compile everything without requiring upstream |
| // modifications, so in the case that this looks like a |
| // rustc_private crate (e.g. a compiler crate) and we also have |
| // the `-Z force-unstable-if-unmarked` flag present (we're |
| // compiling a compiler crate), then let this missing feature |
| // annotation slide. |
| if *feature == "rustc_private" && issue == 27812 { |
| if self.sess.opts.debugging_opts.force_unstable_if_unmarked { |
| return |
| } |
| } |
| |
| let msg = match *reason { |
| Some(ref r) => format!("use of unstable library feature '{}': {}", |
| feature.as_str(), &r), |
| None => format!("use of unstable library feature '{}'", &feature) |
| }; |
| |
| |
| let msp: MultiSpan = span.into(); |
| let cm = &self.sess.parse_sess.codemap(); |
| let span_key = msp.primary_span().and_then(|sp: Span| |
| if sp != DUMMY_SP { |
| let file = cm.lookup_char_pos(sp.lo()).file; |
| if file.name.is_macros() { |
| None |
| } else { |
| Some(span) |
| } |
| } else { |
| None |
| } |
| ); |
| |
| let error_id = (DiagnosticMessageId::StabilityId(issue), span_key, msg.clone()); |
| let fresh = self.sess.one_time_diagnostics.borrow_mut().insert(error_id); |
| if fresh { |
| emit_feature_err(&self.sess.parse_sess, &feature.as_str(), span, |
| GateIssue::Library(Some(issue)), &msg); |
| } |
| } |
| Some(_) => { |
| // Stable APIs are always ok to call and deprecated APIs are |
| // handled by the lint emitting logic above. |
| } |
| None => { |
| span_bug!(span, "encountered unmarked API"); |
| } |
| } |
| } |
| } |
| |
| impl<'a, 'tcx> Visitor<'tcx> for Checker<'a, 'tcx> { |
| /// Because stability levels are scoped lexically, we want to walk |
| /// nested items in the context of the outer item, so enable |
| /// deep-walking. |
| fn nested_visit_map<'this>(&'this mut self) -> NestedVisitorMap<'this, 'tcx> { |
| NestedVisitorMap::OnlyBodies(&self.tcx.hir) |
| } |
| |
| fn visit_item(&mut self, item: &'tcx hir::Item) { |
| match item.node { |
| hir::ItemExternCrate(_) => { |
| // compiler-generated `extern crate` items have a dummy span. |
| if item.span == DUMMY_SP { return } |
| |
| let def_id = self.tcx.hir.local_def_id(item.id); |
| let cnum = match self.tcx.extern_mod_stmt_cnum(def_id) { |
| Some(cnum) => cnum, |
| None => return, |
| }; |
| let def_id = DefId { krate: cnum, index: CRATE_DEF_INDEX }; |
| self.tcx.check_stability(def_id, item.id, item.span); |
| } |
| |
| // For implementations of traits, check the stability of each item |
| // individually as it's possible to have a stable trait with unstable |
| // items. |
| hir::ItemImpl(.., Some(ref t), _, ref impl_item_refs) => { |
| if let Def::Trait(trait_did) = t.path.def { |
| for impl_item_ref in impl_item_refs { |
| let impl_item = self.tcx.hir.impl_item(impl_item_ref.id); |
| let trait_item_def_id = self.tcx.associated_items(trait_did) |
| .find(|item| item.name == impl_item.name).map(|item| item.def_id); |
| if let Some(def_id) = trait_item_def_id { |
| // Pass `DUMMY_NODE_ID` to skip deprecation warnings. |
| self.tcx.check_stability(def_id, ast::DUMMY_NODE_ID, impl_item.span); |
| } |
| } |
| } |
| } |
| |
| // There's no good place to insert stability check for non-Copy unions, |
| // so semi-randomly perform it here in stability.rs |
| hir::ItemUnion(..) if !self.tcx.sess.features.borrow().untagged_unions => { |
| let def_id = self.tcx.hir.local_def_id(item.id); |
| let adt_def = self.tcx.adt_def(def_id); |
| let ty = self.tcx.type_of(def_id); |
| |
| if adt_def.has_dtor(self.tcx) { |
| emit_feature_err(&self.tcx.sess.parse_sess, |
| "untagged_unions", item.span, GateIssue::Language, |
| "unions with `Drop` implementations are unstable"); |
| } else { |
| let param_env = self.tcx.param_env(def_id); |
| if !param_env.can_type_implement_copy(self.tcx, ty, item.span).is_ok() { |
| emit_feature_err(&self.tcx.sess.parse_sess, |
| "untagged_unions", item.span, GateIssue::Language, |
| "unions with non-`Copy` fields are unstable"); |
| } |
| } |
| } |
| |
| _ => (/* pass */) |
| } |
| intravisit::walk_item(self, item); |
| } |
| |
| fn visit_path(&mut self, path: &'tcx hir::Path, id: ast::NodeId) { |
| match path.def { |
| Def::Local(..) | Def::Upvar(..) | |
| Def::PrimTy(..) | Def::SelfTy(..) | Def::Err => {} |
| _ => self.tcx.check_stability(path.def.def_id(), id, path.span) |
| } |
| intravisit::walk_path(self, path) |
| } |
| } |
| |
| impl<'a, 'gcx, 'tcx> TyCtxt<'a, 'gcx, 'tcx> { |
| pub fn lookup_deprecation(self, id: DefId) -> Option<Deprecation> { |
| self.lookup_deprecation_entry(id).map(|depr| depr.attr) |
| } |
| } |
| |
| /// Given the list of enabled features that were not language features (i.e. that |
| /// were expected to be library features), and the list of features used from |
| /// libraries, identify activated features that don't exist and error about them. |
| pub fn check_unused_or_stable_features<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>) { |
| let sess = &tcx.sess; |
| |
| let access_levels = &tcx.privacy_access_levels(LOCAL_CRATE); |
| |
| if tcx.stability().staged_api[&LOCAL_CRATE] { |
| let krate = tcx.hir.krate(); |
| let mut missing = MissingStabilityAnnotations { |
| tcx, |
| access_levels, |
| }; |
| missing.check_missing_stability(ast::CRATE_NODE_ID, krate.span); |
| intravisit::walk_crate(&mut missing, krate); |
| krate.visit_all_item_likes(&mut missing.as_deep_visitor()); |
| } |
| |
| let ref declared_lib_features = sess.features.borrow().declared_lib_features; |
| let mut remaining_lib_features: FxHashMap<Symbol, Span> |
| = declared_lib_features.clone().into_iter().collect(); |
| remaining_lib_features.remove(&Symbol::intern("proc_macro")); |
| |
| for &(ref stable_lang_feature, span) in &sess.features.borrow().declared_stable_lang_features { |
| let version = find_lang_feature_accepted_version(&stable_lang_feature.as_str()) |
| .expect("unexpectedly couldn't find version feature was stabilized"); |
| tcx.lint_node(lint::builtin::STABLE_FEATURES, |
| ast::CRATE_NODE_ID, |
| span, |
| &format_stable_since_msg(version)); |
| } |
| |
| // FIXME(#44232) the `used_features` table no longer exists, so we don't |
| // lint about unknown or unused features. We should reenable |
| // this one day! |
| // |
| // let index = tcx.stability(); |
| // for (used_lib_feature, level) in &index.used_features { |
| // remaining_lib_features.remove(used_lib_feature); |
| // } |
| // |
| // for &span in remaining_lib_features.values() { |
| // tcx.lint_node(lint::builtin::UNUSED_FEATURES, |
| // ast::CRATE_NODE_ID, |
| // span, |
| // "unused or unknown feature"); |
| // } |
| } |
| |
| fn format_stable_since_msg(version: &str) -> String { |
| format!("this feature has been stable since {}. Attribute no longer needed", version) |
| } |
