diff options
Diffstat (limited to 'compiler')
141 files changed, 3166 insertions, 2329 deletions
diff --git a/compiler/rustc_ast/src/ast.rs b/compiler/rustc_ast/src/ast.rs index 328086af183..9d6ee65049a 100644 --- a/compiler/rustc_ast/src/ast.rs +++ b/compiler/rustc_ast/src/ast.rs @@ -901,10 +901,39 @@ pub struct Stmt { pub id: NodeId, pub kind: StmtKind, pub span: Span, - pub tokens: Option<LazyTokenStream>, } impl Stmt { + pub fn tokens(&self) -> Option<&LazyTokenStream> { + match self.kind { + StmtKind::Local(ref local) => local.tokens.as_ref(), + StmtKind::Item(ref item) => item.tokens.as_ref(), + StmtKind::Expr(ref expr) | StmtKind::Semi(ref expr) => expr.tokens.as_ref(), + StmtKind::Empty => None, + StmtKind::MacCall(ref mac) => mac.tokens.as_ref(), + } + } + + pub fn tokens_mut(&mut self) -> Option<&mut LazyTokenStream> { + match self.kind { + StmtKind::Local(ref mut local) => local.tokens.as_mut(), + StmtKind::Item(ref mut item) => item.tokens.as_mut(), + StmtKind::Expr(ref mut expr) | StmtKind::Semi(ref mut expr) => expr.tokens.as_mut(), + StmtKind::Empty => None, + StmtKind::MacCall(ref mut mac) => mac.tokens.as_mut(), + } + } + + pub fn set_tokens(&mut self, tokens: Option<LazyTokenStream>) { + match self.kind { + StmtKind::Local(ref mut local) => local.tokens = tokens, + StmtKind::Item(ref mut item) => item.tokens = tokens, + StmtKind::Expr(ref mut expr) | StmtKind::Semi(ref mut expr) => expr.tokens = tokens, + StmtKind::Empty => {} + StmtKind::MacCall(ref mut mac) => mac.tokens = tokens, + } + } + pub fn has_trailing_semicolon(&self) -> bool { match &self.kind { StmtKind::Semi(_) => true, @@ -912,18 +941,25 @@ impl Stmt { _ => false, } } + + /// Converts a parsed `Stmt` to a `Stmt` with + /// a trailing semicolon. + /// + /// This only modifies the parsed AST struct, not the attached + /// `LazyTokenStream`. The parser is responsible for calling + /// `CreateTokenStream::add_trailing_semi` when there is actually + /// a semicolon in the tokenstream. pub fn add_trailing_semicolon(mut self) -> Self { self.kind = match self.kind { StmtKind::Expr(expr) => StmtKind::Semi(expr), StmtKind::MacCall(mac) => { - StmtKind::MacCall(mac.map(|MacCallStmt { mac, style: _, attrs }| MacCallStmt { - mac, - style: MacStmtStyle::Semicolon, - attrs, + StmtKind::MacCall(mac.map(|MacCallStmt { mac, style: _, attrs, tokens }| { + MacCallStmt { mac, style: MacStmtStyle::Semicolon, attrs, tokens } })) } kind => kind, }; + self } @@ -963,6 +999,7 @@ pub struct MacCallStmt { pub mac: MacCall, pub style: MacStmtStyle, pub attrs: AttrVec, + pub tokens: Option<LazyTokenStream>, } #[derive(Clone, Copy, PartialEq, Encodable, Decodable, Debug)] @@ -988,6 +1025,7 @@ pub struct Local { pub init: Option<P<Expr>>, pub span: Span, pub attrs: AttrVec, + pub tokens: Option<LazyTokenStream>, } /// An arm of a 'match'. @@ -1845,6 +1883,7 @@ impl UintTy { pub struct AssocTyConstraint { pub id: NodeId, pub ident: Ident, + pub gen_args: Option<GenericArgs>, pub kind: AssocTyConstraintKind, pub span: Span, } diff --git a/compiler/rustc_ast/src/lib.rs b/compiler/rustc_ast/src/lib.rs index 6e47ff7d740..8a20dd79685 100644 --- a/compiler/rustc_ast/src/lib.rs +++ b/compiler/rustc_ast/src/lib.rs @@ -34,7 +34,6 @@ macro_rules! unwrap_or { pub mod util { pub mod classify; pub mod comments; - pub mod lev_distance; pub mod literal; pub mod parser; } diff --git a/compiler/rustc_ast/src/mut_visit.rs b/compiler/rustc_ast/src/mut_visit.rs index ddae0ab03e4..c4e92a9f6d1 100644 --- a/compiler/rustc_ast/src/mut_visit.rs +++ b/compiler/rustc_ast/src/mut_visit.rs @@ -441,11 +441,14 @@ pub fn noop_flat_map_arm<T: MutVisitor>(mut arm: Arm, vis: &mut T) -> SmallVec<[ } pub fn noop_visit_ty_constraint<T: MutVisitor>( - AssocTyConstraint { id, ident, kind, span }: &mut AssocTyConstraint, + AssocTyConstraint { id, ident, gen_args, kind, span }: &mut AssocTyConstraint, vis: &mut T, ) { vis.visit_id(id); vis.visit_ident(ident); + if let Some(ref mut gen_args) = gen_args { + vis.visit_generic_args(gen_args); + } match kind { AssocTyConstraintKind::Equality { ref mut ty } => { vis.visit_ty(ty); @@ -576,13 +579,14 @@ pub fn noop_visit_parenthesized_parameter_data<T: MutVisitor>( } pub fn noop_visit_local<T: MutVisitor>(local: &mut P<Local>, vis: &mut T) { - let Local { id, pat, ty, init, span, attrs } = local.deref_mut(); + let Local { id, pat, ty, init, span, attrs, tokens } = local.deref_mut(); vis.visit_id(id); vis.visit_pat(pat); visit_opt(ty, |ty| vis.visit_ty(ty)); visit_opt(init, |init| vis.visit_expr(init)); vis.visit_span(span); visit_thin_attrs(attrs, vis); + visit_lazy_tts(tokens, vis); } pub fn noop_visit_attribute<T: MutVisitor>(attr: &mut Attribute, vis: &mut T) { @@ -1325,16 +1329,12 @@ pub fn noop_filter_map_expr<T: MutVisitor>(mut e: P<Expr>, vis: &mut T) -> Optio } pub fn noop_flat_map_stmt<T: MutVisitor>( - Stmt { kind, mut span, mut id, mut tokens }: Stmt, + Stmt { kind, mut span, mut id }: Stmt, vis: &mut T, ) -> SmallVec<[Stmt; 1]> { vis.visit_id(&mut id); vis.visit_span(&mut span); - visit_lazy_tts(&mut tokens, vis); - noop_flat_map_stmt_kind(kind, vis) - .into_iter() - .map(|kind| Stmt { id, kind, span, tokens: tokens.clone() }) - .collect() + noop_flat_map_stmt_kind(kind, vis).into_iter().map(|kind| Stmt { id, kind, span }).collect() } pub fn noop_flat_map_stmt_kind<T: MutVisitor>( @@ -1351,9 +1351,10 @@ pub fn noop_flat_map_stmt_kind<T: MutVisitor>( StmtKind::Semi(expr) => vis.filter_map_expr(expr).into_iter().map(StmtKind::Semi).collect(), StmtKind::Empty => smallvec![StmtKind::Empty], StmtKind::MacCall(mut mac) => { - let MacCallStmt { mac: mac_, style: _, attrs } = mac.deref_mut(); + let MacCallStmt { mac: mac_, style: _, attrs, tokens } = mac.deref_mut(); vis.visit_mac_call(mac_); visit_thin_attrs(attrs, vis); + visit_lazy_tts(tokens, vis); smallvec![StmtKind::MacCall(mac)] } } diff --git a/compiler/rustc_ast/src/token.rs b/compiler/rustc_ast/src/token.rs index 2bba7e618c0..f583825fbb3 100644 --- a/compiler/rustc_ast/src/token.rs +++ b/compiler/rustc_ast/src/token.rs @@ -785,13 +785,20 @@ impl Nonterminal { /// See issue #73345 for more details. /// FIXME(#73933): Remove this eventually. pub fn pretty_printing_compatibility_hack(&self) -> bool { - if let NtItem(item) = self { - let name = item.ident.name; - if name == sym::ProceduralMasqueradeDummyType || name == sym::ProcMacroHack { - if let ast::ItemKind::Enum(enum_def, _) = &item.kind { - if let [variant] = &*enum_def.variants { - return variant.ident.name == sym::Input; - } + let item = match self { + NtItem(item) => item, + NtStmt(stmt) => match &stmt.kind { + ast::StmtKind::Item(item) => item, + _ => return false, + }, + _ => return false, + }; + + let name = item.ident.name; + if name == sym::ProceduralMasqueradeDummyType || name == sym::ProcMacroHack { + if let ast::ItemKind::Enum(enum_def, _) = &item.kind { + if let [variant] = &*enum_def.variants { + return variant.ident.name == sym::Input; } } } diff --git a/compiler/rustc_ast/src/tokenstream.rs b/compiler/rustc_ast/src/tokenstream.rs index fe67b905bf3..b2207f22816 100644 --- a/compiler/rustc_ast/src/tokenstream.rs +++ b/compiler/rustc_ast/src/tokenstream.rs @@ -121,10 +121,14 @@ where } pub trait CreateTokenStream: sync::Send + sync::Sync { + fn add_trailing_semi(&self) -> Box<dyn CreateTokenStream>; fn create_token_stream(&self) -> TokenStream; } impl CreateTokenStream for TokenStream { + fn add_trailing_semi(&self) -> Box<dyn CreateTokenStream> { + panic!("Cannot call `add_trailing_semi` on a `TokenStream`!"); + } fn create_token_stream(&self) -> TokenStream { self.clone() } @@ -141,6 +145,13 @@ impl LazyTokenStream { LazyTokenStream(Lrc::new(Box::new(inner))) } + /// Extends the captured stream by one token, + /// which must be a trailing semicolon. This + /// affects the `TokenStream` created by `make_tokenstream`. + pub fn add_trailing_semi(&self) -> LazyTokenStream { + LazyTokenStream(Lrc::new(self.0.add_trailing_semi())) + } + pub fn create_token_stream(&self) -> TokenStream { self.0.create_token_stream() } diff --git a/compiler/rustc_ast/src/visit.rs b/compiler/rustc_ast/src/visit.rs index 560064182e1..61426a838de 100644 --- a/compiler/rustc_ast/src/visit.rs +++ b/compiler/rustc_ast/src/visit.rs @@ -485,6 +485,9 @@ pub fn walk_assoc_ty_constraint<'a, V: Visitor<'a>>( constraint: &'a AssocTyConstraint, ) { visitor.visit_ident(constraint.ident); + if let Some(ref gen_args) = constraint.gen_args { + visitor.visit_generic_args(gen_args.span(), gen_args); + } match constraint.kind { AssocTyConstraintKind::Equality { ref ty } => { visitor.visit_ty(ty); @@ -686,7 +689,7 @@ pub fn walk_stmt<'a, V: Visitor<'a>>(visitor: &mut V, statement: &'a Stmt) { StmtKind::Expr(ref expr) | StmtKind::Semi(ref expr) => visitor.visit_expr(expr), StmtKind::Empty => {} StmtKind::MacCall(ref mac) => { - let MacCallStmt { ref mac, style: _, ref attrs } = **mac; + let MacCallStmt { ref mac, style: _, ref attrs, tokens: _ } = **mac; visitor.visit_mac_call(mac); for attr in attrs.iter() { visitor.visit_attribute(attr); diff --git a/compiler/rustc_ast_lowering/src/expr.rs b/compiler/rustc_ast_lowering/src/expr.rs index f83fc29577b..314e5103cc2 100644 --- a/compiler/rustc_ast_lowering/src/expr.rs +++ b/compiler/rustc_ast_lowering/src/expr.rs @@ -353,7 +353,6 @@ impl<'hir> LoweringContext<'_, 'hir> { let else_arm = self.arm(else_pat, else_expr); // Handle then + scrutinee: - let then_expr = self.lower_block_expr(then); let (then_pat, scrutinee, desugar) = match cond.kind { // `<pat> => <then>`: ExprKind::Let(ref pat, ref scrutinee) => { @@ -375,6 +374,7 @@ impl<'hir> LoweringContext<'_, 'hir> { (pat, cond, hir::MatchSource::IfDesugar { contains_else_clause }) } }; + let then_expr = self.lower_block_expr(then); let then_arm = self.arm(then_pat, self.arena.alloc(then_expr)); hir::ExprKind::Match(scrutinee, arena_vec![self; then_arm, else_arm], desugar) @@ -400,7 +400,6 @@ impl<'hir> LoweringContext<'_, 'hir> { }; // Handle then + scrutinee: - let then_expr = self.lower_block_expr(body); let (then_pat, scrutinee, desugar, source) = match cond.kind { ExprKind::Let(ref pat, ref scrutinee) => { // to: @@ -440,6 +439,7 @@ impl<'hir> LoweringContext<'_, 'hir> { (pat, cond, hir::MatchSource::WhileDesugar, hir::LoopSource::While) } }; + let then_expr = self.lower_block_expr(body); let then_arm = self.arm(then_pat, self.arena.alloc(then_expr)); // `match <scrutinee> { ... }` diff --git a/compiler/rustc_ast_lowering/src/item.rs b/compiler/rustc_ast_lowering/src/item.rs index d353bc19f7a..eef6d38aa05 100644 --- a/compiler/rustc_ast_lowering/src/item.rs +++ b/compiler/rustc_ast_lowering/src/item.rs @@ -43,6 +43,7 @@ impl<'a> Visitor<'a> for ItemLowerer<'a, '_, '_> { items: BTreeSet::new(), trait_items: BTreeSet::new(), impl_items: BTreeSet::new(), + foreign_items: BTreeSet::new(), }, ); @@ -105,6 +106,18 @@ impl<'a> Visitor<'a> for ItemLowerer<'a, '_, '_> { visit::walk_assoc_item(self, item, ctxt); } + + fn visit_foreign_item(&mut self, item: &'a ForeignItem) { + self.lctx.allocate_hir_id_counter(item.id); + self.lctx.with_hir_id_owner(item.id, |lctx| { + let hir_item = lctx.lower_foreign_item(item); + let id = hir::ForeignItemId { hir_id: hir_item.hir_id }; + lctx.foreign_items.insert(id, hir_item); + lctx.modules.get_mut(&lctx.current_module).unwrap().foreign_items.insert(id); + }); + + visit::walk_foreign_item(self, item); + } } impl<'hir> LoweringContext<'_, 'hir> { @@ -304,7 +317,12 @@ impl<'hir> LoweringContext<'_, 'hir> { }) } ItemKind::Mod(ref m) => hir::ItemKind::Mod(self.lower_mod(m)), - ItemKind::ForeignMod(ref nm) => hir::ItemKind::ForeignMod(self.lower_foreign_mod(nm)), + ItemKind::ForeignMod(ref fm) => hir::ItemKind::ForeignMod { + abi: fm.abi.map_or(abi::Abi::C, |abi| self.lower_abi(abi)), + items: self + .arena + .alloc_from_iter(fm.items.iter().map(|x| self.lower_foreign_item_ref(x))), + }, ItemKind::GlobalAsm(ref ga) => hir::ItemKind::GlobalAsm(self.lower_global_asm(ga)), ItemKind::TyAlias(_, ref gen, _, Some(ref ty)) => { // We lower @@ -704,10 +722,12 @@ impl<'hir> LoweringContext<'_, 'hir> { } } - fn lower_foreign_mod(&mut self, fm: &ForeignMod) -> hir::ForeignMod<'hir> { - hir::ForeignMod { - abi: fm.abi.map_or(abi::Abi::C, |abi| self.lower_abi(abi)), - items: self.arena.alloc_from_iter(fm.items.iter().map(|x| self.lower_foreign_item(x))), + fn lower_foreign_item_ref(&mut self, i: &ForeignItem) -> hir::ForeignItemRef<'hir> { + hir::ForeignItemRef { + id: hir::ForeignItemId { hir_id: self.lower_node_id(i.id) }, + ident: i.ident, + span: i.span, + vis: self.lower_visibility(&i.vis, Some(i.id)), } } diff --git a/compiler/rustc_ast_lowering/src/lib.rs b/compiler/rustc_ast_lowering/src/lib.rs index d93655e5905..2e1b5a74a7b 100644 --- a/compiler/rustc_ast_lowering/src/lib.rs +++ b/compiler/rustc_ast_lowering/src/lib.rs @@ -101,6 +101,7 @@ struct LoweringContext<'a, 'hir: 'a> { trait_items: BTreeMap<hir::TraitItemId, hir::TraitItem<'hir>>, impl_items: BTreeMap<hir::ImplItemId, hir::ImplItem<'hir>>, + foreign_items: BTreeMap<hir::ForeignItemId, hir::ForeignItem<'hir>>, bodies: BTreeMap<hir::BodyId, hir::Body<'hir>>, exported_macros: Vec<hir::MacroDef<'hir>>, non_exported_macro_attrs: Vec<ast::Attribute>, @@ -298,6 +299,7 @@ pub fn lower_crate<'a, 'hir>( items: BTreeMap::new(), trait_items: BTreeMap::new(), impl_items: BTreeMap::new(), + foreign_items: BTreeMap::new(), bodies: BTreeMap::new(), trait_impls: BTreeMap::new(), modules: BTreeMap::new(), @@ -425,7 +427,6 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> { /// declared for every type and trait definition. struct MiscCollector<'tcx, 'lowering, 'hir> { lctx: &'tcx mut LoweringContext<'lowering, 'hir>, - hir_id_owner: Option<NodeId>, } impl MiscCollector<'_, '_, '_> { @@ -452,30 +453,9 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> { } } } - - fn with_hir_id_owner<T>( - &mut self, - owner: Option<NodeId>, - f: impl FnOnce(&mut Self) -> T, - ) -> T { - let old = mem::replace(&mut self.hir_id_owner, owner); - let r = f(self); - self.hir_id_owner = old; - r - } } impl<'tcx> Visitor<'tcx> for MiscCollector<'tcx, '_, '_> { - fn visit_pat(&mut self, p: &'tcx Pat) { - if let PatKind::Paren(..) | PatKind::Rest = p.kind { - // Doesn't generate a HIR node - } else if let Some(owner) = self.hir_id_owner { - self.lctx.lower_node_id_with_owner(p.id, owner); - } - - visit::walk_pat(self, p) - } - fn visit_item(&mut self, item: &'tcx Item) { let hir_id = self.lctx.allocate_hir_id_counter(item.id); @@ -499,24 +479,17 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> { _ => {} } - self.with_hir_id_owner(Some(item.id), |this| { - visit::walk_item(this, item); - }); + visit::walk_item(self, item); } fn visit_assoc_item(&mut self, item: &'tcx AssocItem, ctxt: AssocCtxt) { self.lctx.allocate_hir_id_counter(item.id); - let owner = match (&item.kind, ctxt) { - // Ignore patterns in trait methods without bodies. - (AssocItemKind::Fn(_, _, _, None), AssocCtxt::Trait) => None, - _ => Some(item.id), - }; - self.with_hir_id_owner(owner, |this| visit::walk_assoc_item(this, item, ctxt)); + visit::walk_assoc_item(self, item, ctxt); } - fn visit_foreign_item(&mut self, i: &'tcx ForeignItem) { - // Ignore patterns in foreign items - self.with_hir_id_owner(None, |this| visit::walk_foreign_item(this, i)); + fn visit_foreign_item(&mut self, item: &'tcx ForeignItem) { + self.lctx.allocate_hir_id_counter(item.id); + visit::walk_foreign_item(self, item); } fn visit_ty(&mut self, t: &'tcx Ty) { @@ -527,18 +500,14 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> { // Mirrors visit::walk_fn_decl for parameter in &f.decl.inputs { // We don't lower the ids of argument patterns - self.with_hir_id_owner(None, |this| { - this.visit_pat(¶meter.pat); - }); + self.visit_pat(¶meter.pat); self.visit_ty(¶meter.ty) } self.visit_fn_ret_ty(&f.decl.output) } TyKind::ImplTrait(def_node_id, _) => { self.lctx.allocate_hir_id_counter(def_node_id); - self.with_hir_id_owner(Some(def_node_id), |this| { - visit::walk_ty(this, t); - }); + visit::walk_ty(self, t); } _ => visit::walk_ty(self, t), } @@ -548,7 +517,7 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> { self.lower_node_id(CRATE_NODE_ID); debug_assert!(self.node_id_to_hir_id[CRATE_NODE_ID] == Some(hir::CRATE_HIR_ID)); - visit::walk_crate(&mut MiscCollector { lctx: &mut self, hir_id_owner: None }, c); + visit::walk_crate(&mut MiscCollector { lctx: &mut self }, c); visit::walk_crate(&mut item::ItemLowerer { lctx: &mut self }, c); let module = self.lower_mod(&c.module); @@ -586,6 +555,7 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> { items: self.items, trait_items: self.trait_items, impl_items: self.impl_items, + foreign_items: self.foreign_items, bodies: self.bodies, body_ids, trait_impls: self.trait_impls, @@ -1038,6 +1008,13 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> { ) -> hir::TypeBinding<'hir> { debug!("lower_assoc_ty_constraint(constraint={:?}, itctx={:?})", constraint, itctx); + if let Some(ref gen_args) = constraint.gen_args { + self.sess.span_fatal( + gen_args.span(), + "generic associated types in trait paths are currently not implemented", + ); + } + let kind = match constraint.kind { AssocTyConstraintKind::Equality { ref ty } => { hir::TypeBindingKind::Equality { ty: self.lower_ty(ty, itctx) } diff --git a/compiler/rustc_ast_passes/src/ast_validation.rs b/compiler/rustc_ast_passes/src/ast_validation.rs index 08ebcbf381a..4ec3e39facc 100644 --- a/compiler/rustc_ast_passes/src/ast_validation.rs +++ b/compiler/rustc_ast_passes/src/ast_validation.rs @@ -1372,16 +1372,18 @@ fn deny_equality_constraints( if param.ident == *ident { let param = ident; match &full_path.segments[qself.position..] { - [PathSegment { ident, .. }] => { + [PathSegment { ident, args, .. }] => { // Make a new `Path` from `foo::Bar` to `Foo<Bar = RhsTy>`. let mut assoc_path = full_path.clone(); // Remove `Bar` from `Foo::Bar`. assoc_path.segments.pop(); let len = assoc_path.segments.len() - 1; + let gen_args = args.as_ref().map(|p| (**p).clone()); // Build `<Bar = RhsTy>`. let arg = AngleBracketedArg::Constraint(AssocTyConstraint { id: rustc_ast::node_id::DUMMY_NODE_ID, ident: *ident, + gen_args, kind: AssocTyConstraintKind::Equality { ty: predicate.rhs_ty.clone(), }, diff --git a/compiler/rustc_ast_passes/src/feature_gate.rs b/compiler/rustc_ast_passes/src/feature_gate.rs index 181783441f3..5b75fbf339b 100644 --- a/compiler/rustc_ast_passes/src/feature_gate.rs +++ b/compiler/rustc_ast_passes/src/feature_gate.rs @@ -370,7 +370,7 @@ impl<'a> Visitor<'a> for PostExpansionVisitor<'a> { ast::ItemKind::Trait(ast::IsAuto::Yes, ..) => { gate_feature_post!( &self, - optin_builtin_traits, + auto_traits, i.span, "auto traits are experimental and possibly buggy" ); diff --git a/compiler/rustc_ast_passes/src/lib.rs b/compiler/rustc_ast_passes/src/lib.rs index bfe30441980..7487421e709 100644 --- a/compiler/rustc_ast_passes/src/lib.rs +++ b/compiler/rustc_ast_passes/src/lib.rs @@ -6,6 +6,7 @@ #![feature(bindings_after_at)] #![feature(iter_is_partitioned)] +#![recursion_limit = "256"] pub mod ast_validation; pub mod feature_gate; diff --git a/compiler/rustc_builtin_macros/src/deriving/debug.rs b/compiler/rustc_builtin_macros/src/deriving/debug.rs index 9381264f498..5c21329069b 100644 --- a/compiler/rustc_builtin_macros/src/deriving/debug.rs +++ b/compiler/rustc_builtin_macros/src/deriving/debug.rs @@ -132,6 +132,7 @@ fn stmt_let_underscore(cx: &mut ExtCtxt<'_>, sp: Span, expr: P<ast::Expr>) -> as id: ast::DUMMY_NODE_ID, span: sp, attrs: ast::AttrVec::new(), + tokens: None, }); - ast::Stmt { id: ast::DUMMY_NODE_ID, kind: ast::StmtKind::Local(local), span: sp, tokens: None } + ast::Stmt { id: ast::DUMMY_NODE_ID, kind: ast::StmtKind::Local(local), span: sp } } diff --git a/compiler/rustc_builtin_macros/src/deriving/mod.rs b/compiler/rustc_builtin_macros/src/deriving/mod.rs index 72d94af4694..1651180817b 100644 --- a/compiler/rustc_builtin_macros/src/deriving/mod.rs +++ b/compiler/rustc_builtin_macros/src/deriving/mod.rs @@ -54,7 +54,26 @@ impl MultiItemModifier for BuiltinDerive { // so we are doing it here in a centralized way. let span = ecx.with_def_site_ctxt(span); let mut items = Vec::new(); - (self.0)(ecx, span, meta_item, &item, &mut |a| items.push(a)); + match item { + Annotatable::Stmt(stmt) => { + if let ast::StmtKind::Item(item) = stmt.into_inner().kind { + (self.0)(ecx, span, meta_item, &Annotatable::Item(item), &mut |a| { + // Cannot use 'ecx.stmt_item' here, because we need to pass 'ecx' + // to the function + items.push(Annotatable::Stmt(P(ast::Stmt { + id: ast::DUMMY_NODE_ID, + kind: ast::StmtKind::Item(a.expect_item()), + span, + }))); + }); + } else { + unreachable!("should have already errored on non-item statement") + } + } + _ => { + (self.0)(ecx, span, meta_item, &item, &mut |a| items.push(a)); + } + } ExpandResult::Ready(items) } } diff --git a/compiler/rustc_builtin_macros/src/global_allocator.rs b/compiler/rustc_builtin_macros/src/global_allocator.rs index 8478fcfbf09..e976805d9dd 100644 --- a/compiler/rustc_builtin_macros/src/global_allocator.rs +++ b/compiler/rustc_builtin_macros/src/global_allocator.rs @@ -4,7 +4,7 @@ use rustc_ast::expand::allocator::{ AllocatorKind, AllocatorMethod, AllocatorTy, ALLOCATOR_METHODS, }; use rustc_ast::ptr::P; -use rustc_ast::{self as ast, Attribute, Expr, FnHeader, FnSig, Generics, Param}; +use rustc_ast::{self as ast, Attribute, Expr, FnHeader, FnSig, Generics, Param, StmtKind}; use rustc_ast::{ItemKind, Mutability, Stmt, Ty, TyKind, Unsafe}; use rustc_expand::base::{Annotatable, ExtCtxt}; use rustc_span::symbol::{kw, sym, Ident, Symbol}; @@ -14,7 +14,7 @@ pub fn expand( ecx: &mut ExtCtxt<'_>, _span: Span, meta_item: &ast::MetaItem, - item: Annotatable, + mut item: Annotatable, ) -> Vec<Annotatable> { check_builtin_macro_attribute(ecx, meta_item, sym::global_allocator); @@ -22,6 +22,17 @@ pub fn expand( ecx.sess.parse_sess.span_diagnostic.span_err(item.span(), "allocators must be statics"); vec![item] }; + let orig_item = item.clone(); + let mut is_stmt = false; + + // Allow using `#[global_allocator]` on an item statement + if let Annotatable::Stmt(stmt) = &item { + if let StmtKind::Item(item_) = &stmt.kind { + item = Annotatable::Item(item_.clone()); + is_stmt = true; + } + } + let item = match item { Annotatable::Item(item) => match item.kind { ItemKind::Static(..) => item, @@ -41,9 +52,14 @@ pub fn expand( let const_ty = ecx.ty(span, TyKind::Tup(Vec::new())); let const_body = ecx.expr_block(ecx.block(span, stmts)); let const_item = ecx.item_const(span, Ident::new(kw::Underscore, span), const_ty, const_body); + let const_item = if is_stmt { + Annotatable::Stmt(P(ecx.stmt_item(span, const_item))) + } else { + Annotatable::Item(const_item) + }; // Return the original item and the new methods. - vec![Annotatable::Item(item), Annotatable::Item(const_item)] + vec![orig_item, const_item] } struct AllocFnFactory<'a, 'b> { diff --git a/compiler/rustc_builtin_macros/src/test.rs b/compiler/rustc_builtin_macros/src/test.rs index 1de0b32f519..25d3f46da6c 100644 --- a/compiler/rustc_builtin_macros/src/test.rs +++ b/compiler/rustc_builtin_macros/src/test.rs @@ -4,6 +4,7 @@ use crate::util::check_builtin_macro_attribute; use rustc_ast as ast; use rustc_ast::attr; +use rustc_ast::ptr::P; use rustc_ast_pretty::pprust; use rustc_expand::base::*; use rustc_session::Session; @@ -78,8 +79,16 @@ pub fn expand_test_or_bench( return vec![]; } - let item = match item { - Annotatable::Item(i) => i, + let (item, is_stmt) = match item { + Annotatable::Item(i) => (i, false), + Annotatable::Stmt(stmt) if matches!(stmt.kind, ast::StmtKind::Item(_)) => { + // FIXME: Use an 'if let' guard once they are implemented + if let ast::StmtKind::Item(i) = stmt.into_inner().kind { + (i, true) + } else { + unreachable!() + } + } other => { cx.struct_span_err( other.span(), @@ -304,14 +313,25 @@ pub fn expand_test_or_bench( tracing::debug!("synthetic test item:\n{}\n", pprust::item_to_string(&test_const)); - vec![ - // Access to libtest under a hygienic name - Annotatable::Item(test_extern), - // The generated test case - Annotatable::Item(test_const), - // The original item - Annotatable::Item(item), - ] + if is_stmt { + vec![ + // Access to libtest under a hygienic name + Annotatable::Stmt(P(cx.stmt_item(sp, test_extern))), + // The generated test case + Annotatable::Stmt(P(cx.stmt_item(sp, test_const))), + // The original item + Annotatable::Stmt(P(cx.stmt_item(sp, item))), + ] + } else { + vec![ + // Access to libtest under a hygienic name + Annotatable::Item(test_extern), + // The generated test case + Annotatable::Item(test_const), + // The original item + Annotatable::Item(item), + ] + } } fn item_path(mod_path: &[Ident], item_ident: &Ident) -> String { diff --git a/compiler/rustc_codegen_cranelift/example/mini_core.rs b/compiler/rustc_codegen_cranelift/example/mini_core.rs index ce07fe83df1..10cba992056 100644 --- a/compiler/rustc_codegen_cranelift/example/mini_core.rs +++ b/compiler/rustc_codegen_cranelift/example/mini_core.rs @@ -1,6 +1,6 @@ #![feature( no_core, lang_items, intrinsics, unboxed_closures, type_ascription, extern_types, - untagged_unions, decl_macro, rustc_attrs, transparent_unions, optin_builtin_traits, + untagged_unions, decl_macro, rustc_attrs, transparent_unions, auto_traits, thread_local, )] #![no_core] diff --git a/compiler/rustc_codegen_llvm/src/coverageinfo/mapgen.rs b/compiler/rustc_codegen_llvm/src/coverageinfo/mapgen.rs index 41827a91ba4..85aaa7e8893 100644 --- a/compiler/rustc_codegen_llvm/src/coverageinfo/mapgen.rs +++ b/compiler/rustc_codegen_llvm/src/coverageinfo/mapgen.rs @@ -4,7 +4,7 @@ use crate::llvm; use llvm::coverageinfo::CounterMappingRegion; use rustc_codegen_ssa::coverageinfo::map::{Counter, CounterExpression}; -use rustc_codegen_ssa::traits::{BaseTypeMethods, ConstMethods}; +use rustc_codegen_ssa::traits::ConstMethods; use rustc_data_structures::fx::FxIndexSet; use rustc_llvm::RustString; use rustc_middle::mir::coverage::CodeRegion; @@ -15,9 +15,9 @@ use tracing::debug; /// Generates and exports the Coverage Map. /// -/// This Coverage Map complies with Coverage Mapping Format version 3 (zero-based encoded as 2), -/// as defined at [LLVM Code Coverage Mapping Format](https://github.com/rust-lang/llvm-project/blob/llvmorg-8.0.0/llvm/docs/CoverageMappingFormat.rst#llvm-code-coverage-mapping-format) -/// and published in Rust's current (July 2020) fork of LLVM. This version is supported by the +/// This Coverage Map complies with Coverage Mapping Format version 4 (zero-based encoded as 3), +/// as defined at [LLVM Code Coverage Mapping Format](https://github.com/rust-lang/llvm-project/blob/rustc/11.0-2020-10-12/llvm/docs/CoverageMappingFormat.rst#llvm-code-coverage-mapping-format) +/// and published in Rust's current (November 2020) fork of LLVM. This version is supported by the /// LLVM coverage tools (`llvm-profdata` and `llvm-cov`) bundled with Rust's fork of LLVM. /// /// Consequently, Rust's bundled version of Clang also generates Coverage Maps compliant with @@ -26,6 +26,13 @@ use tracing::debug; /// undocumented details in Clang's implementation (that may or may not be important) were also /// replicated for Rust's Coverage Map. pub fn finalize<'ll, 'tcx>(cx: &CodegenCx<'ll, 'tcx>) { + // Ensure LLVM supports Coverage Map Version 4 (encoded as a zero-based value: 3). + // If not, the LLVM Version must be less than 11. + let version = coverageinfo::mapping_version(); + if version != 3 { + cx.tcx.sess.fatal("rustc option `-Z instrument-coverage` requires LLVM 11 or higher."); + } + let function_coverage_map = match cx.coverage_context() { Some(ctx) => ctx.take_function_coverage_map(), None => return, @@ -38,46 +45,50 @@ pub fn finalize<'ll, 'tcx>(cx: &CodegenCx<'ll, 'tcx>) { let mut mapgen = CoverageMapGenerator::new(); // Encode coverage mappings and generate function records - let mut function_records = Vec::<&'ll llvm::Value>::new(); - let coverage_mappings_buffer = llvm::build_byte_buffer(|coverage_mappings_buffer| { - for (instance, function_coverage) in function_coverage_map.into_iter() { - debug!("Generate coverage map for: {:?}", instance); - - let mangled_function_name = cx.tcx.symbol_name(instance).to_string(); - let function_source_hash = function_coverage.source_hash(); - let (expressions, counter_regions) = - function_coverage.get_expressions_and_counter_regions(); - - let old_len = coverage_mappings_buffer.len(); - mapgen.write_coverage_mappings(expressions, counter_regions, coverage_mappings_buffer); - let mapping_data_size = coverage_mappings_buffer.len() - old_len; - debug_assert!( - mapping_data_size > 0, - "Every `FunctionCoverage` should have at least one counter" - ); - - let function_record = mapgen.make_function_record( - cx, - mangled_function_name, - function_source_hash, - mapping_data_size, - ); - function_records.push(function_record); - } - }); + let mut function_data = Vec::new(); + for (instance, function_coverage) in function_coverage_map { + debug!("Generate coverage map for: {:?}", instance); + + let mangled_function_name = cx.tcx.symbol_name(instance).to_string(); + let function_source_hash = function_coverage.source_hash(); + let (expressions, counter_regions) = + function_coverage.get_expressions_and_counter_regions(); + + let coverage_mapping_buffer = llvm::build_byte_buffer(|coverage_mapping_buffer| { + mapgen.write_coverage_mapping(expressions, counter_regions, coverage_mapping_buffer); + }); + debug_assert!( + coverage_mapping_buffer.len() > 0, + "Every `FunctionCoverage` should have at least one counter" + ); + + function_data.push((mangled_function_name, function_source_hash, coverage_mapping_buffer)); + } // Encode all filenames referenced by counters/expressions in this module let filenames_buffer = llvm::build_byte_buffer(|filenames_buffer| { coverageinfo::write_filenames_section_to_buffer(&mapgen.filenames, filenames_buffer); }); + let filenames_size = filenames_buffer.len(); + let filenames_val = cx.const_bytes(&filenames_buffer[..]); + let filenames_ref = coverageinfo::hash_bytes(filenames_buffer); + // Generate the LLVM IR representation of the coverage map and store it in a well-known global - mapgen.save_generated_coverage_map( - cx, - function_records, - filenames_buffer, - coverage_mappings_buffer, - ); + let cov_data_val = mapgen.generate_coverage_map(cx, version, filenames_size, filenames_val); + + for (mangled_function_name, function_source_hash, coverage_mapping_buffer) in function_data { + save_function_record( + cx, + mangled_function_name, + function_source_hash, + filenames_ref, + coverage_mapping_buffer, + ); + } + + // Save the coverage data value to LLVM IR + coverageinfo::save_cov_data_to_mod(cx, cov_data_val); } struct CoverageMapGenerator { @@ -92,12 +103,12 @@ impl CoverageMapGenerator { /// Using the `expressions` and `counter_regions` collected for the current function, generate /// the `mapping_regions` and `virtual_file_mapping`, and capture any new filenames. Then use /// LLVM APIs to encode the `virtual_file_mapping`, `expressions`, and `mapping_regions` into - /// the given `coverage_mappings` byte buffer, compliant with the LLVM Coverage Mapping format. - fn write_coverage_mappings( + /// the given `coverage_mapping` byte buffer, compliant with the LLVM Coverage Mapping format. + fn write_coverage_mapping( &mut self, expressions: Vec<CounterExpression>, counter_regions: impl Iterator<Item = (Counter, &'a CodeRegion)>, - coverage_mappings_buffer: &RustString, + coverage_mapping_buffer: &RustString, ) { let mut counter_regions = counter_regions.collect::<Vec<_>>(); if counter_regions.is_empty() { @@ -145,89 +156,75 @@ impl CoverageMapGenerator { virtual_file_mapping, expressions, mapping_regions, - coverage_mappings_buffer, + coverage_mapping_buffer, ); } - /// Generate and return the function record `Value` - fn make_function_record( - &mut self, - cx: &CodegenCx<'ll, 'tcx>, - mangled_function_name: String, - function_source_hash: u64, - mapping_data_size: usize, - ) -> &'ll llvm::Value { - let name_ref = coverageinfo::compute_hash(&mangled_function_name); - let name_ref_val = cx.const_u64(name_ref); - let mapping_data_size_val = cx.const_u32(mapping_data_size as u32); - let func_hash_val = cx.const_u64(function_source_hash); - cx.const_struct( - &[name_ref_val, mapping_data_size_val, func_hash_val], - /*packed=*/ true, - ) - } - - /// Combine the filenames and coverage mappings buffers, construct coverage map header and the - /// array of function records, and combine everything into the complete coverage map. Save the - /// coverage map data into the LLVM IR as a static global using a specific, well-known section - /// and name. - fn save_generated_coverage_map( + /// Construct coverage map header and the array of function records, and combine them into the + /// coverage map. Save the coverage map data into the LLVM IR as a static global using a + /// specific, well-known section and name. + fn generate_coverage_map( self, cx: &CodegenCx<'ll, 'tcx>, - function_records: Vec<&'ll llvm::Value>, - filenames_buffer: Vec<u8>, - mut coverage_mappings_buffer: Vec<u8>, - ) { - // Concatenate the encoded filenames and encoded coverage mappings, and add additional zero - // bytes as-needed to ensure 8-byte alignment. - let mut coverage_size = coverage_mappings_buffer.len(); - let filenames_size = filenames_buffer.len(); - let remaining_bytes = - (filenames_size + coverage_size) % coverageinfo::COVMAP_VAR_ALIGN_BYTES; - if remaining_bytes > 0 { - let pad = coverageinfo::COVMAP_VAR_ALIGN_BYTES - remaining_bytes; - coverage_mappings_buffer.append(&mut [0].repeat(pad)); - coverage_size += pad; - } - let filenames_and_coverage_mappings = [filenames_buffer, coverage_mappings_buffer].concat(); - let filenames_and_coverage_mappings_val = - cx.const_bytes(&filenames_and_coverage_mappings[..]); - - debug!( - "cov map: n_records = {}, filenames_size = {}, coverage_size = {}, 0-based version = {}", - function_records.len(), - filenames_size, - coverage_size, - coverageinfo::mapping_version() - ); + version: u32, + filenames_size: usize, + filenames_val: &'ll llvm::Value, + ) -> &'ll llvm::Value { + debug!("cov map: filenames_size = {}, 0-based version = {}", filenames_size, version); - // Create the coverage data header - let n_records_val = cx.const_u32(function_records.len() as u32); + // Create the coverage data header (Note, fields 0 and 2 are now always zero, + // as of `llvm::coverage::CovMapVersion::Version4`.) + let zero_was_n_records_val = cx.const_u32(0); let filenames_size_val = cx.const_u32(filenames_size as u32); - let coverage_size_val = cx.const_u32(coverage_size as u32); - let version_val = cx.const_u32(coverageinfo::mapping_version()); + let zero_was_coverage_size_val = cx.const_u32(0); + let version_val = cx.const_u32(version); let cov_data_header_val = cx.const_struct( - &[n_records_val, filenames_size_val, coverage_size_val, version_val], + &[zero_was_n_records_val, filenames_size_val, zero_was_coverage_size_val, version_val], /*packed=*/ false, ); - // Create the function records array - let name_ref_from_u64 = cx.type_i64(); - let mapping_data_size_from_u32 = cx.type_i32(); - let func_hash_from_u64 = cx.type_i64(); - let function_record_ty = cx.type_struct( - &[name_ref_from_u64, mapping_data_size_from_u32, func_hash_from_u64], - /*packed=*/ true, - ); - let function_records_val = cx.const_array(function_record_ty, &function_records[..]); - // Create the complete LLVM coverage data value to add to the LLVM IR - let cov_data_val = cx.const_struct( - &[cov_data_header_val, function_records_val, filenames_and_coverage_mappings_val], - /*packed=*/ false, - ); - - // Save the coverage data value to LLVM IR - coverageinfo::save_map_to_mod(cx, cov_data_val); + cx.const_struct(&[cov_data_header_val, filenames_val], /*packed=*/ false) } } + +/// Construct a function record and combine it with the function's coverage mapping data. +/// Save the function record into the LLVM IR as a static global using a +/// specific, well-known section and name. +fn save_function_record( + cx: &CodegenCx<'ll, 'tcx>, + mangled_function_name: String, + function_source_hash: u64, + filenames_ref: u64, + coverage_mapping_buffer: Vec<u8>, +) { + // Concatenate the encoded coverage mappings + let coverage_mapping_size = coverage_mapping_buffer.len(); + let coverage_mapping_val = cx.const_bytes(&coverage_mapping_buffer[..]); + + let func_name_hash = coverageinfo::hash_str(&mangled_function_name); + let func_name_hash_val = cx.const_u64(func_name_hash); + let coverage_mapping_size_val = cx.const_u32(coverage_mapping_size as u32); + let func_hash_val = cx.const_u64(function_source_hash); + let filenames_ref_val = cx.const_u64(filenames_ref); + let func_record_val = cx.const_struct( + &[ + func_name_hash_val, + coverage_mapping_size_val, + func_hash_val, + filenames_ref_val, + coverage_mapping_val, + ], + /*packed=*/ true, + ); + + // At the present time, the coverage map for Rust assumes every instrumented function `is_used`. + // Note that Clang marks functions as "unused" in `CodeGenPGO::emitEmptyCounterMapping`. (See: + // https://github.com/rust-lang/llvm-project/blob/de02a75e398415bad4df27b4547c25b896c8bf3b/clang%2Flib%2FCodeGen%2FCodeGenPGO.cpp#L877-L878 + // for example.) + // + // It's not yet clear if or how this may be applied to Rust in the future, but the `is_used` + // argument is available and handled similarly. + let is_used = true; + coverageinfo::save_func_record_to_mod(cx, func_name_hash, func_record_val, is_used); +} diff --git a/compiler/rustc_codegen_llvm/src/coverageinfo/mod.rs b/compiler/rustc_codegen_llvm/src/coverageinfo/mod.rs index e21e03822eb..e777f363eb0 100644 --- a/compiler/rustc_codegen_llvm/src/coverageinfo/mod.rs +++ b/compiler/rustc_codegen_llvm/src/coverageinfo/mod.rs @@ -23,7 +23,7 @@ use tracing::debug; pub mod mapgen; -const COVMAP_VAR_ALIGN_BYTES: usize = 8; +const VAR_ALIGN_BYTES: usize = 8; /// A context object for maintaining all state needed by the coverageinfo module. pub struct CrateCoverageContext<'tcx> { @@ -177,17 +177,20 @@ pub(crate) fn write_mapping_to_buffer( ); } } +pub(crate) fn hash_str(strval: &str) -> u64 { + let strval = CString::new(strval).expect("null error converting hashable str to C string"); + unsafe { llvm::LLVMRustCoverageHashCString(strval.as_ptr()) } +} -pub(crate) fn compute_hash(name: &str) -> u64 { - let name = CString::new(name).expect("null error converting hashable name to C string"); - unsafe { llvm::LLVMRustCoverageComputeHash(name.as_ptr()) } +pub(crate) fn hash_bytes(bytes: Vec<u8>) -> u64 { + unsafe { llvm::LLVMRustCoverageHashByteArray(bytes.as_ptr().cast(), bytes.len()) } } pub(crate) fn mapping_version() -> u32 { unsafe { llvm::LLVMRustCoverageMappingVersion() } } -pub(crate) fn save_map_to_mod<'ll, 'tcx>( +pub(crate) fn save_cov_data_to_mod<'ll, 'tcx>( cx: &CodegenCx<'ll, 'tcx>, cov_data_val: &'ll llvm::Value, ) { @@ -198,7 +201,7 @@ pub(crate) fn save_map_to_mod<'ll, 'tcx>( debug!("covmap var name: {:?}", covmap_var_name); let covmap_section_name = llvm::build_string(|s| unsafe { - llvm::LLVMRustCoverageWriteSectionNameToString(cx.llmod, s); + llvm::LLVMRustCoverageWriteMapSectionNameToString(cx.llmod, s); }) .expect("Rust Coverage section name failed UTF-8 conversion"); debug!("covmap section name: {:?}", covmap_section_name); @@ -206,8 +209,43 @@ pub(crate) fn save_map_to_mod<'ll, 'tcx>( let llglobal = llvm::add_global(cx.llmod, cx.val_ty(cov_data_val), &covmap_var_name); llvm::set_initializer(llglobal, cov_data_val); llvm::set_global_constant(llglobal, true); - llvm::set_linkage(llglobal, llvm::Linkage::InternalLinkage); + llvm::set_linkage(llglobal, llvm::Linkage::PrivateLinkage); llvm::set_section(llglobal, &covmap_section_name); - llvm::set_alignment(llglobal, COVMAP_VAR_ALIGN_BYTES); + llvm::set_alignment(llglobal, VAR_ALIGN_BYTES); + cx.add_used_global(llglobal); +} + +pub(crate) fn save_func_record_to_mod<'ll, 'tcx>( + cx: &CodegenCx<'ll, 'tcx>, + func_name_hash: u64, + func_record_val: &'ll llvm::Value, + is_used: bool, +) { + // Assign a name to the function record. This is used to merge duplicates. + // + // In LLVM, a "translation unit" (effectively, a `Crate` in Rust) can describe functions that + // are included-but-not-used. If (or when) Rust generates functions that are + // included-but-not-used, note that a dummy description for a function included-but-not-used + // in a Crate can be replaced by full description provided by a different Crate. The two kinds + // of descriptions play distinct roles in LLVM IR; therefore, assign them different names (by + // appending "u" to the end of the function record var name, to prevent `linkonce_odr` merging. + let func_record_var_name = + format!("__covrec_{:X}{}", func_name_hash, if is_used { "u" } else { "" }); + debug!("function record var name: {:?}", func_record_var_name); + + let func_record_section_name = llvm::build_string(|s| unsafe { + llvm::LLVMRustCoverageWriteFuncSectionNameToString(cx.llmod, s); + }) + .expect("Rust Coverage function record section name failed UTF-8 conversion"); + debug!("function record section name: {:?}", func_record_section_name); + + let llglobal = llvm::add_global(cx.llmod, cx.val_ty(func_record_val), &func_record_var_name); + llvm::set_initializer(llglobal, func_record_val); + llvm::set_global_constant(llglobal, true); + llvm::set_linkage(llglobal, llvm::Linkage::LinkOnceODRLinkage); + llvm::set_visibility(llglobal, llvm::Visibility::Hidden); + llvm::set_section(llglobal, &func_record_section_name); + llvm::set_alignment(llglobal, VAR_ALIGN_BYTES); + llvm::set_comdat(cx.llmod, llglobal, &func_record_var_name); cx.add_used_global(llglobal); } diff --git a/compiler/rustc_codegen_llvm/src/llvm/ffi.rs b/compiler/rustc_codegen_llvm/src/llvm/ffi.rs index 8b15c8b0eb6..41482d18946 100644 --- a/compiler/rustc_codegen_llvm/src/llvm/ffi.rs +++ b/compiler/rustc_codegen_llvm/src/llvm/ffi.rs @@ -642,7 +642,7 @@ pub type InlineAsmDiagHandler = unsafe extern "C" fn(&SMDiagnostic, *const c_voi pub mod coverageinfo { use super::coverage_map; - /// Aligns with [llvm::coverage::CounterMappingRegion::RegionKind](https://github.com/rust-lang/llvm-project/blob/rustc/10.0-2020-05-05/llvm/include/llvm/ProfileData/Coverage/CoverageMapping.h#L205-L221) + /// Aligns with [llvm::coverage::CounterMappingRegion::RegionKind](https://github.com/rust-lang/llvm-project/blob/rustc/11.0-2020-10-12/llvm/include/llvm/ProfileData/Coverage/CoverageMapping.h#L206-L222) #[derive(Copy, Clone, Debug)] #[repr(C)] pub enum RegionKind { @@ -665,13 +665,13 @@ pub mod coverageinfo { /// This struct provides LLVM's representation of a "CoverageMappingRegion", encoded into the /// coverage map, in accordance with the - /// [LLVM Code Coverage Mapping Format](https://github.com/rust-lang/llvm-project/blob/llvmorg-8.0.0/llvm/docs/CoverageMappingFormat.rst#llvm-code-coverage-mapping-format). + /// [LLVM Code Coverage Mapping Format](https://github.com/rust-lang/llvm-project/blob/rustc/11.0-2020-10-12/llvm/docs/CoverageMappingFormat.rst#llvm-code-coverage-mapping-format). /// The struct composes fields representing the `Counter` type and value(s) (injected counter /// ID, or expression type and operands), the source file (an indirect index into a "filenames /// array", encoded separately), and source location (start and end positions of the represented /// code region). /// - /// Aligns with [llvm::coverage::CounterMappingRegion](https://github.com/rust-lang/llvm-project/blob/rustc/10.0-2020-05-05/llvm/include/llvm/ProfileData/Coverage/CoverageMapping.h#L223-L226) + /// Aligns with [llvm::coverage::CounterMappingRegion](https://github.com/rust-lang/llvm-project/blob/rustc/11.0-2020-10-12/llvm/include/llvm/ProfileData/Coverage/CoverageMapping.h#L224-L227) /// Important: The Rust struct layout (order and types of fields) must match its C++ /// counterpart. #[derive(Copy, Clone, Debug)] @@ -1791,10 +1791,14 @@ extern "C" { pub fn LLVMRustCoverageCreatePGOFuncNameVar(F: &'a Value, FuncName: *const c_char) -> &'a Value; - pub fn LLVMRustCoverageComputeHash(Name: *const c_char) -> u64; + pub fn LLVMRustCoverageHashCString(StrVal: *const c_char) -> u64; + pub fn LLVMRustCoverageHashByteArray(Bytes: *const c_char, NumBytes: size_t) -> u64; #[allow(improper_ctypes)] - pub fn LLVMRustCoverageWriteSectionNameToString(M: &Module, Str: &RustString); + pub fn LLVMRustCoverageWriteMapSectionNameToString(M: &Module, Str: &RustString); + + #[allow(improper_ctypes)] + pub fn LLVMRustCoverageWriteFuncSectionNameToString(M: &Module, Str: &RustString); #[allow(improper_ctypes)] pub fn LLVMRustCoverageWriteMappingVarNameToString(Str: &RustString); diff --git a/compiler/rustc_codegen_llvm/src/llvm/mod.rs b/compiler/rustc_codegen_llvm/src/llvm/mod.rs index 53a404ee019..fc40065a966 100644 --- a/compiler/rustc_codegen_llvm/src/llvm/mod.rs +++ b/compiler/rustc_codegen_llvm/src/llvm/mod.rs @@ -220,12 +220,24 @@ pub fn set_linkage(llglobal: &Value, linkage: Linkage) { } } +pub fn set_visibility(llglobal: &Value, visibility: Visibility) { + unsafe { + LLVMRustSetVisibility(llglobal, visibility); + } +} + pub fn set_alignment(llglobal: &Value, bytes: usize) { unsafe { ffi::LLVMSetAlignment(llglobal, bytes as c_uint); } } +pub fn set_comdat(llmod: &Module, llglobal: &Value, name: &str) { + unsafe { + LLVMRustSetComdat(llmod, llglobal, name.as_ptr().cast(), name.len()); + } +} + /// Safe wrapper around `LLVMGetParam`, because segfaults are no fun. pub fn get_param(llfn: &Value, index: c_uint) -> &Value { unsafe { diff --git a/compiler/rustc_codegen_ssa/src/back/link.rs b/compiler/rustc_codegen_ssa/src/back/link.rs index 5a627a0efa3..22e2aa3b5c8 100644 --- a/compiler/rustc_codegen_ssa/src/back/link.rs +++ b/compiler/rustc_codegen_ssa/src/back/link.rs @@ -2090,9 +2090,10 @@ fn add_apple_sdk(cmd: &mut dyn Linker, sess: &Session, flavor: LinkerFlavor) { ("aarch64", "tvos") => "appletvos", ("x86_64", "tvos") => "appletvsimulator", ("arm", "ios") => "iphoneos", + ("aarch64", "ios") if llvm_target.contains("macabi") => "macosx", ("aarch64", "ios") => "iphoneos", ("x86", "ios") => "iphonesimulator", - ("x86_64", "ios") if llvm_target.contains("macabi") => "macosx10.15", + ("x86_64", "ios") if llvm_target.contains("macabi") => "macosx", ("x86_64", "ios") => "iphonesimulator", _ => { sess.err(&format!("unsupported arch `{}` for os `{}`", arch, os)); diff --git a/compiler/rustc_codegen_ssa/src/coverageinfo/ffi.rs b/compiler/rustc_codegen_ssa/src/coverageinfo/ffi.rs index bcac2c90fdc..af6c476292b 100644 --- a/compiler/rustc_codegen_ssa/src/coverageinfo/ffi.rs +++ b/compiler/rustc_codegen_ssa/src/coverageinfo/ffi.rs @@ -1,6 +1,6 @@ use rustc_middle::mir::coverage::{CounterValueReference, MappedExpressionIndex}; -/// Aligns with [llvm::coverage::Counter::CounterKind](https://github.com/rust-lang/llvm-project/blob/rustc/10.0-2020-05-05/llvm/include/llvm/ProfileData/Coverage/CoverageMapping.h#L91) +/// Aligns with [llvm::coverage::Counter::CounterKind](https://github.com/rust-lang/llvm-project/blob/rustc/11.0-2020-10-12/llvm/include/llvm/ProfileData/Coverage/CoverageMapping.h#L206-L222) #[derive(Copy, Clone, Debug)] #[repr(C)] pub enum CounterKind { @@ -17,7 +17,7 @@ pub enum CounterKind { /// `instrprof.increment()`) /// * For `CounterKind::Expression`, `id` is the index into the coverage map's array of /// counter expressions. -/// Aligns with [llvm::coverage::Counter](https://github.com/rust-lang/llvm-project/blob/rustc/10.0-2020-05-05/llvm/include/llvm/ProfileData/Coverage/CoverageMapping.h#L98-L99) +/// Aligns with [llvm::coverage::Counter](https://github.com/rust-lang/llvm-project/blob/rustc/11.0-2020-10-12/llvm/include/llvm/ProfileData/Coverage/CoverageMapping.h#L99-L100) /// Important: The Rust struct layout (order and types of fields) must match its C++ counterpart. #[derive(Copy, Clone, Debug)] #[repr(C)] @@ -41,7 +41,7 @@ impl Counter { } } -/// Aligns with [llvm::coverage::CounterExpression::ExprKind](https://github.com/rust-lang/llvm-project/blob/rustc/10.0-2020-05-05/llvm/include/llvm/ProfileData/Coverage/CoverageMapping.h#L146) +/// Aligns with [llvm::coverage::CounterExpression::ExprKind](https://github.com/rust-lang/llvm-project/blob/rustc/11.0-2020-10-12/llvm/include/llvm/ProfileData/Coverage/CoverageMapping.h#L147) #[derive(Copy, Clone, Debug)] #[repr(C)] pub enum ExprKind { @@ -49,7 +49,7 @@ pub enum ExprKind { Add = 1, } -/// Aligns with [llvm::coverage::CounterExpression](https://github.com/rust-lang/llvm-project/blob/rustc/10.0-2020-05-05/llvm/include/llvm/ProfileData/Coverage/CoverageMapping.h#L147-L148) +/// Aligns with [llvm::coverage::CounterExpression](https://github.com/rust-lang/llvm-project/blob/rustc/11.0-2020-10-12/llvm/include/llvm/ProfileData/Coverage/CoverageMapping.h#L148-L149) /// Important: The Rust struct layout (order and types of fields) must match its C++ /// counterpart. #[derive(Copy, Clone, Debug)] diff --git a/compiler/rustc_codegen_ssa/src/mir/block.rs b/compiler/rustc_codegen_ssa/src/mir/block.rs index 9651d0505e6..e59832a8eed 100644 --- a/compiler/rustc_codegen_ssa/src/mir/block.rs +++ b/compiler/rustc_codegen_ssa/src/mir/block.rs @@ -451,7 +451,7 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> { Inhabited, ZeroValid, UninitValid, - }; + } let panic_intrinsic = intrinsic.and_then(|i| match i { sym::assert_inhabited => Some(AssertIntrinsic::Inhabited), sym::assert_zero_valid => Some(AssertIntrinsic::ZeroValid), diff --git a/compiler/rustc_data_structures/src/lib.rs b/compiler/rustc_data_structures/src/lib.rs index 01604477c3e..d903a557c7f 100644 --- a/compiler/rustc_data_structures/src/lib.rs +++ b/compiler/rustc_data_structures/src/lib.rs @@ -15,7 +15,8 @@ #![feature(fn_traits)] #![feature(int_bits_const)] #![feature(min_specialization)] -#![feature(optin_builtin_traits)] +#![cfg_attr(bootstrap, feature(optin_builtin_traits))] +#![cfg_attr(not(bootstrap), feature(auto_traits))] #![feature(nll)] #![feature(allow_internal_unstable)] #![feature(hash_raw_entry)] diff --git a/compiler/rustc_driver/src/lib.rs b/compiler/rustc_driver/src/lib.rs index e49e456792b..c1741bfaaba 100644 --- a/compiler/rustc_driver/src/lib.rs +++ b/compiler/rustc_driver/src/lib.rs @@ -248,11 +248,18 @@ fn run_compiler( interface::run_compiler(config, |compiler| { let sopts = &compiler.session().opts; if sopts.describe_lints { - let lint_store = rustc_lint::new_lint_store( + let mut lint_store = rustc_lint::new_lint_store( sopts.debugging_opts.no_interleave_lints, compiler.session().unstable_options(), ); - describe_lints(compiler.session(), &lint_store, false); + let registered_lints = + if let Some(register_lints) = compiler.register_lints() { + register_lints(compiler.session(), &mut lint_store); + true + } else { + false + }; + describe_lints(compiler.session(), &lint_store, registered_lints); return; } let should_stop = RustcDefaultCalls::print_crate_info( @@ -954,10 +961,7 @@ Available lint options: match (loaded_plugins, plugin.len(), plugin_groups.len()) { (false, 0, _) | (false, _, 0) => { - println!( - "Compiler plugins can provide additional lints and lint groups. To see a \ - listing of these, re-run `rustc -W help` with a crate filename." - ); + println!("Lint tools like Clippy can provide additional lints and lint groups."); } (false, ..) => panic!("didn't load lint plugins but got them anyway!"), (true, 0, 0) => println!("This crate does not load any lint plugins or lint groups."), @@ -1284,11 +1288,30 @@ pub fn init_env_logger(env: &str) { Ok(s) if s.is_empty() => return, Ok(_) => {} } + let color_logs = match std::env::var(String::from(env) + "_COLOR") { + Ok(value) => match value.as_ref() { + "always" => true, + "never" => false, + "auto" => stdout_isatty(), + _ => early_error( + ErrorOutputType::default(), + &format!( + "invalid log color value '{}': expected one of always, never, or auto", + value + ), + ), + }, + Err(std::env::VarError::NotPresent) => stdout_isatty(), + Err(std::env::VarError::NotUnicode(_value)) => early_error( + ErrorOutputType::default(), + "non-Unicode log color value: expected one of always, never, or auto", + ), + }; let filter = tracing_subscriber::EnvFilter::from_env(env); let layer = tracing_tree::HierarchicalLayer::default() .with_writer(io::stderr) .with_indent_lines(true) - .with_ansi(true) + .with_ansi(color_logs) .with_targets(true) .with_wraparound(10) .with_verbose_exit(true) @@ -1314,7 +1337,7 @@ pub fn main() -> ! { arg.into_string().unwrap_or_else(|arg| { early_error( ErrorOutputType::default(), - &format!("Argument {} is not valid Unicode: {:?}", i, arg), + &format!("argument {} is not valid Unicode: {:?}", i, arg), ) }) }) diff --git a/compiler/rustc_error_codes/src/error_codes/E0198.md b/compiler/rustc_error_codes/src/error_codes/E0198.md index 90f1e542874..1238165cb88 100644 --- a/compiler/rustc_error_codes/src/error_codes/E0198.md +++ b/compiler/rustc_error_codes/src/error_codes/E0198.md @@ -16,7 +16,7 @@ unsafe. This will compile: ```ignore (ignore auto_trait future compatibility warning) -#![feature(optin_builtin_traits)] +#![feature(auto_traits)] struct Foo; diff --git a/compiler/rustc_error_codes/src/error_codes/E0321.md b/compiler/rustc_error_codes/src/error_codes/E0321.md index bfcdabfe9de..bcfc12897c5 100644 --- a/compiler/rustc_error_codes/src/error_codes/E0321.md +++ b/compiler/rustc_error_codes/src/error_codes/E0321.md @@ -4,7 +4,7 @@ or enum type. Erroneous code example: ```compile_fail,E0321 -#![feature(optin_builtin_traits)] +#![feature(auto_traits)] struct Foo; diff --git a/compiler/rustc_error_codes/src/error_codes/E0567.md b/compiler/rustc_error_codes/src/error_codes/E0567.md index 05cf8fed031..bc13ee4c04c 100644 --- a/compiler/rustc_error_codes/src/error_codes/E0567.md +++ b/compiler/rustc_error_codes/src/error_codes/E0567.md @@ -3,7 +3,7 @@ Generics have been used on an auto trait. Erroneous code example: ```compile_fail,E0567 -#![feature(optin_builtin_traits)] +#![feature(auto_traits)] auto trait Generic<T> {} // error! # fn main() {} @@ -16,7 +16,7 @@ parameters. To fix this issue, just remove the generics: ``` -#![feature(optin_builtin_traits)] +#![feature(auto_traits)] auto trait Generic {} // ok! # fn main() {} diff --git a/compiler/rustc_error_codes/src/error_codes/E0568.md b/compiler/rustc_error_codes/src/error_codes/E0568.md index a37381f1cbd..17b3f5e31bd 100644 --- a/compiler/rustc_error_codes/src/error_codes/E0568.md +++ b/compiler/rustc_error_codes/src/error_codes/E0568.md @@ -3,7 +3,7 @@ A super trait has been added to an auto trait. Erroneous code example: ```compile_fail,E0568 -#![feature(optin_builtin_traits)] +#![feature(auto_traits)] auto trait Bound : Copy {} // error! @@ -18,7 +18,7 @@ all the existing types could implement `Bound` because very few of them have the To fix this issue, just remove the super trait: ``` -#![feature(optin_builtin_traits)] +#![feature(auto_traits)] auto trait Bound {} // ok! diff --git a/compiler/rustc_expand/src/base.rs b/compiler/rustc_expand/src/base.rs index 1c76c31e1a7..b1071bf4308 100644 --- a/compiler/rustc_expand/src/base.rs +++ b/compiler/rustc_expand/src/base.rs @@ -234,6 +234,15 @@ impl Annotatable { pub fn derive_allowed(&self) -> bool { match *self { + Annotatable::Stmt(ref stmt) => match stmt.kind { + ast::StmtKind::Item(ref item) => match item.kind { + ast::ItemKind::Struct(..) + | ast::ItemKind::Enum(..) + | ast::ItemKind::Union(..) => true, + _ => false, + }, + _ => false, + }, Annotatable::Item(ref item) => match item.kind { ast::ItemKind::Struct(..) | ast::ItemKind::Enum(..) | ast::ItemKind::Union(..) => { true @@ -365,7 +374,6 @@ macro_rules! make_stmts_default { id: ast::DUMMY_NODE_ID, span: e.span, kind: ast::StmtKind::Expr(e), - tokens: None }] }) }; @@ -608,7 +616,6 @@ impl MacResult for DummyResult { id: ast::DUMMY_NODE_ID, kind: ast::StmtKind::Expr(DummyResult::raw_expr(self.span, self.is_error)), span: self.span, - tokens: None }]) } diff --git a/compiler/rustc_expand/src/build.rs b/compiler/rustc_expand/src/build.rs index 30f0fc6cddf..fe67b401fcc 100644 --- a/compiler/rustc_expand/src/build.rs +++ b/compiler/rustc_expand/src/build.rs @@ -140,12 +140,7 @@ impl<'a> ExtCtxt<'a> { } pub fn stmt_expr(&self, expr: P<ast::Expr>) -> ast::Stmt { - ast::Stmt { - id: ast::DUMMY_NODE_ID, - span: expr.span, - kind: ast::StmtKind::Expr(expr), - tokens: None, - } + ast::Stmt { id: ast::DUMMY_NODE_ID, span: expr.span, kind: ast::StmtKind::Expr(expr) } } pub fn stmt_let(&self, sp: Span, mutbl: bool, ident: Ident, ex: P<ast::Expr>) -> ast::Stmt { @@ -162,13 +157,9 @@ impl<'a> ExtCtxt<'a> { id: ast::DUMMY_NODE_ID, span: sp, attrs: AttrVec::new(), - }); - ast::Stmt { - id: ast::DUMMY_NODE_ID, - kind: ast::StmtKind::Local(local), - span: sp, tokens: None, - } + }); + ast::Stmt { id: ast::DUMMY_NODE_ID, kind: ast::StmtKind::Local(local), span: sp } } // Generates `let _: Type;`, which is usually used for type assertions. @@ -180,17 +171,13 @@ impl<'a> ExtCtxt<'a> { id: ast::DUMMY_NODE_ID, span, attrs: AttrVec::new(), + tokens: None, }); - ast::Stmt { id: ast::DUMMY_NODE_ID, kind: ast::StmtKind::Local(local), span, tokens: None } + ast::Stmt { id: ast::DUMMY_NODE_ID, kind: ast::StmtKind::Local(local), span } } pub fn stmt_item(&self, sp: Span, item: P<ast::Item>) -> ast::Stmt { - ast::Stmt { - id: ast::DUMMY_NODE_ID, - kind: ast::StmtKind::Item(item), - span: sp, - tokens: None, - } + ast::Stmt { id: ast::DUMMY_NODE_ID, kind: ast::StmtKind::Item(item), span: sp } } pub fn block_expr(&self, expr: P<ast::Expr>) -> P<ast::Block> { @@ -200,7 +187,6 @@ impl<'a> ExtCtxt<'a> { id: ast::DUMMY_NODE_ID, span: expr.span, kind: ast::StmtKind::Expr(expr), - tokens: None, }], ) } diff --git a/compiler/rustc_expand/src/expand.rs b/compiler/rustc_expand/src/expand.rs index 5be2fee8b38..4ba75c21cf0 100644 --- a/compiler/rustc_expand/src/expand.rs +++ b/compiler/rustc_expand/src/expand.rs @@ -795,7 +795,14 @@ impl<'a, 'b> MacroExpander<'a, 'b> { | Annotatable::TraitItem(_) | Annotatable::ImplItem(_) | Annotatable::ForeignItem(_) => return, - Annotatable::Stmt(_) => "statements", + Annotatable::Stmt(stmt) => { + // Attributes are stable on item statements, + // but unstable on all other kinds of statements + if stmt.is_item() { + return; + } + "statements" + } Annotatable::Expr(_) => "expressions", Annotatable::Arm(..) | Annotatable::Field(..) @@ -1266,9 +1273,13 @@ impl<'a, 'b> MutVisitor for InvocationCollector<'a, 'b> { // we'll expand attributes on expressions separately if !stmt.is_expr() { - // FIXME: Handle custom attributes on statements (#15701). - let attr = - if stmt.is_item() { None } else { self.take_first_attr_no_derive(&mut stmt) }; + let attr = if stmt.is_item() { + self.take_first_attr(&mut stmt) + } else { + // Ignore derives on non-item statements for backwards compatibility. + // This will result in a unused attribute warning + self.take_first_attr_no_derive(&mut stmt) + }; if let Some(attr) = attr { return self @@ -1278,7 +1289,7 @@ impl<'a, 'b> MutVisitor for InvocationCollector<'a, 'b> { } if let StmtKind::MacCall(mac) = stmt.kind { - let MacCallStmt { mac, style, attrs } = mac.into_inner(); + let MacCallStmt { mac, style, attrs, tokens: _ } = mac.into_inner(); self.check_attributes(&attrs); let mut placeholder = self.collect_bang(mac, stmt.span, AstFragmentKind::Stmts).make_stmts(); @@ -1295,10 +1306,10 @@ impl<'a, 'b> MutVisitor for InvocationCollector<'a, 'b> { } // The placeholder expander gives ids to statements, so we avoid folding the id here. - let ast::Stmt { id, kind, span, tokens } = stmt; + let ast::Stmt { id, kind, span } = stmt; noop_flat_map_stmt_kind(kind, self) .into_iter() - .map(|kind| ast::Stmt { id, kind, span, tokens: tokens.clone() }) + .map(|kind| ast::Stmt { id, kind, span }) .collect() } diff --git a/compiler/rustc_expand/src/placeholders.rs b/compiler/rustc_expand/src/placeholders.rs index f0e5826f403..ce19e813bb3 100644 --- a/compiler/rustc_expand/src/placeholders.rs +++ b/compiler/rustc_expand/src/placeholders.rs @@ -104,8 +104,9 @@ pub fn placeholder( mac: mac_placeholder(), style: ast::MacStmtStyle::Braces, attrs: ast::AttrVec::new(), + tokens: None, }); - ast::Stmt { id, span, kind: ast::StmtKind::MacCall(mac), tokens: None } + ast::Stmt { id, span, kind: ast::StmtKind::MacCall(mac) } }]), AstFragmentKind::Arms => AstFragment::Arms(smallvec![ast::Arm { attrs: Default::default(), @@ -331,12 +332,8 @@ impl<'a, 'b> MutVisitor for PlaceholderExpander<'a, 'b> { // FIXME: We will need to preserve the original semicolon token and // span as part of #15701 - let empty_stmt = ast::Stmt { - id: ast::DUMMY_NODE_ID, - kind: ast::StmtKind::Empty, - span: DUMMY_SP, - tokens: None, - }; + let empty_stmt = + ast::Stmt { id: ast::DUMMY_NODE_ID, kind: ast::StmtKind::Empty, span: DUMMY_SP }; if let Some(stmt) = stmts.pop() { if stmt.has_trailing_semicolon() { diff --git a/compiler/rustc_expand/src/proc_macro.rs b/compiler/rustc_expand/src/proc_macro.rs index dea167740ed..36707a1ae27 100644 --- a/compiler/rustc_expand/src/proc_macro.rs +++ b/compiler/rustc_expand/src/proc_macro.rs @@ -1,6 +1,7 @@ use crate::base::{self, *}; use crate::proc_macro_server; +use rustc_ast::ptr::P; use rustc_ast::token; use rustc_ast::tokenstream::{TokenStream, TokenTree}; use rustc_ast::{self as ast, *}; @@ -74,8 +75,20 @@ impl MultiItemModifier for ProcMacroDerive { _meta_item: &ast::MetaItem, item: Annotatable, ) -> ExpandResult<Vec<Annotatable>, Annotatable> { + // We need special handling for statement items + // (e.g. `fn foo() { #[derive(Debug)] struct Bar; }`) + let mut is_stmt = false; let item = match item { Annotatable::Item(item) => token::NtItem(item), + Annotatable::Stmt(stmt) => { + is_stmt = true; + assert!(stmt.is_item()); + + // A proc macro can't observe the fact that we're passing + // them an `NtStmt` - it can only see the underlying tokens + // of the wrapped item + token::NtStmt(stmt.into_inner()) + } _ => unreachable!(), }; let input = if item.pretty_printing_compatibility_hack() { @@ -106,7 +119,13 @@ impl MultiItemModifier for ProcMacroDerive { loop { match parser.parse_item() { Ok(None) => break, - Ok(Some(item)) => items.push(Annotatable::Item(item)), + Ok(Some(item)) => { + if is_stmt { + items.push(Annotatable::Stmt(P(ecx.stmt_item(span, item)))); + } else { + items.push(Annotatable::Item(item)); + } + } Err(mut err) => { err.emit(); break; diff --git a/compiler/rustc_feature/src/active.rs b/compiler/rustc_feature/src/active.rs index a0355079247..75337634d3f 100644 --- a/compiler/rustc_feature/src/active.rs +++ b/compiler/rustc_feature/src/active.rs @@ -149,9 +149,6 @@ declare_features! ( /// Allows using the `#[linkage = ".."]` attribute. (active, linkage, "1.0.0", Some(29603), None), - /// Allows features specific to OIBIT (auto traits). - (active, optin_builtin_traits, "1.0.0", Some(13231), None), - /// Allows using `box` in patterns (RFC 469). (active, box_patterns, "1.0.0", Some(29641), None), @@ -215,6 +212,10 @@ declare_features! ( /// purpose as `#[allow_internal_unstable]`. (active, rustc_allow_const_fn_unstable, "1.49.0", Some(69399), None), + /// Allows features specific to auto traits. + /// Renamed from `optin_builtin_traits`. + (active, auto_traits, "1.50.0", Some(13231), None), + // no-tracking-issue-end // ------------------------------------------------------------------------- diff --git a/compiler/rustc_feature/src/removed.rs b/compiler/rustc_feature/src/removed.rs index a480ddc7f34..07bd1602cda 100644 --- a/compiler/rustc_feature/src/removed.rs +++ b/compiler/rustc_feature/src/removed.rs @@ -71,6 +71,10 @@ declare_features! ( /// Allows using custom attributes (RFC 572). (removed, custom_attribute, "1.0.0", Some(29642), None, Some("removed in favor of `#![register_tool]` and `#![register_attr]`")), + /// Allows features specific to OIBIT (now called auto traits). + /// Renamed to `auto_traits`. + (removed, optin_builtin_traits, "1.0.0", Some(13231), None, + Some("renamed to `auto_traits`")), (removed, pushpop_unsafe, "1.2.0", None, None, None), (removed, needs_allocator, "1.4.0", Some(27389), None, Some("subsumed by `#![feature(allocator_internals)]`")), @@ -113,7 +117,6 @@ declare_features! ( Some("removed in favor of `#![feature(marker_trait_attr)]`")), /// Allows `#[no_debug]`. (removed, no_debug, "1.43.0", Some(29721), None, Some("removed due to lack of demand")), - /// Allows comparing raw pointers during const eval. (removed, const_compare_raw_pointers, "1.46.0", Some(53020), None, Some("cannot be allowed in const eval in any meaningful way")), diff --git a/compiler/rustc_hir/src/arena.rs b/compiler/rustc_hir/src/arena.rs index 85ab7906d25..44dfdcfccab 100644 --- a/compiler/rustc_hir/src/arena.rs +++ b/compiler/rustc_hir/src/arena.rs @@ -29,6 +29,7 @@ macro_rules! arena_types { [] field_pat: rustc_hir::FieldPat<$tcx>, [] fn_decl: rustc_hir::FnDecl<$tcx>, [] foreign_item: rustc_hir::ForeignItem<$tcx>, + [few] foreign_item_ref: rustc_hir::ForeignItemRef<$tcx>, [] impl_item_ref: rustc_hir::ImplItemRef<$tcx>, [few] inline_asm: rustc_hir::InlineAsm<$tcx>, [few] llvm_inline_asm: rustc_hir::LlvmInlineAsm<$tcx>, diff --git a/compiler/rustc_hir/src/hir.rs b/compiler/rustc_hir/src/hir.rs index 4497c8c0eaa..f01d4417105 100644 --- a/compiler/rustc_hir/src/hir.rs +++ b/compiler/rustc_hir/src/hir.rs @@ -579,6 +579,7 @@ pub struct ModuleItems { pub items: BTreeSet<HirId>, pub trait_items: BTreeSet<TraitItemId>, pub impl_items: BTreeSet<ImplItemId>, + pub foreign_items: BTreeSet<ForeignItemId>, } /// A type representing only the top-level module. @@ -612,6 +613,7 @@ pub struct Crate<'hir> { pub trait_items: BTreeMap<TraitItemId, TraitItem<'hir>>, pub impl_items: BTreeMap<ImplItemId, ImplItem<'hir>>, + pub foreign_items: BTreeMap<ForeignItemId, ForeignItem<'hir>>, pub bodies: BTreeMap<BodyId, Body<'hir>>, pub trait_impls: BTreeMap<DefId, Vec<HirId>>, @@ -644,6 +646,10 @@ impl Crate<'hir> { &self.impl_items[&id] } + pub fn foreign_item(&self, id: ForeignItemId) -> &ForeignItem<'hir> { + &self.foreign_items[&id] + } + pub fn body(&self, id: BodyId) -> &Body<'hir> { &self.bodies[&id] } @@ -673,6 +679,10 @@ impl Crate<'_> { for impl_item in self.impl_items.values() { visitor.visit_impl_item(impl_item); } + + for foreign_item in self.foreign_items.values() { + visitor.visit_foreign_item(foreign_item); + } } /// A parallel version of `visit_all_item_likes`. @@ -695,6 +705,11 @@ impl Crate<'_> { par_for_each_in(&self.impl_items, |(_, impl_item)| { visitor.visit_impl_item(impl_item); }); + }, + { + par_for_each_in(&self.foreign_items, |(_, foreign_item)| { + visitor.visit_foreign_item(foreign_item); + }); } ); } @@ -1840,7 +1855,7 @@ pub struct FnSig<'hir> { } // The bodies for items are stored "out of line", in a separate -// hashmap in the `Crate`. Here we just record the node-id of the item +// hashmap in the `Crate`. Here we just record the hir-id of the item // so it can fetched later. #[derive(Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Encodable, Debug)] pub struct TraitItemId { @@ -1884,7 +1899,7 @@ pub enum TraitItemKind<'hir> { } // The bodies for items are stored "out of line", in a separate -// hashmap in the `Crate`. Here we just record the node-id of the item +// hashmap in the `Crate`. Here we just record the hir-id of the item // so it can fetched later. #[derive(Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Encodable, Debug)] pub struct ImplItemId { @@ -2269,12 +2284,6 @@ pub struct Mod<'hir> { pub item_ids: &'hir [ItemId], } -#[derive(Debug, HashStable_Generic)] -pub struct ForeignMod<'hir> { - pub abi: Abi, - pub items: &'hir [ForeignItem<'hir>], -} - #[derive(Encodable, Debug, HashStable_Generic)] pub struct GlobalAsm { pub asm: Symbol, @@ -2432,7 +2441,7 @@ impl VariantData<'hir> { } // The bodies for items are stored "out of line", in a separate -// hashmap in the `Crate`. Here we just record the node-id of the item +// hashmap in the `Crate`. Here we just record the hir-id of the item // so it can fetched later. #[derive(Copy, Clone, Encodable, Debug)] pub struct ItemId { @@ -2521,7 +2530,7 @@ pub enum ItemKind<'hir> { /// A module. Mod(Mod<'hir>), /// An external module, e.g. `extern { .. }`. - ForeignMod(ForeignMod<'hir>), + ForeignMod { abi: Abi, items: &'hir [ForeignItemRef<'hir>] }, /// Module-level inline assembly (from `global_asm!`). GlobalAsm(&'hir GlobalAsm), /// A type alias, e.g., `type Foo = Bar<u8>`. @@ -2614,6 +2623,29 @@ pub enum AssocItemKind { Type, } +// The bodies for items are stored "out of line", in a separate +// hashmap in the `Crate`. Here we just record the hir-id of the item +// so it can fetched later. +#[derive(Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Encodable, Debug)] +pub struct ForeignItemId { + pub hir_id: HirId, +} + +/// A reference from a foreign block to one of its items. This +/// contains the item's ID, naturally, but also the item's name and +/// some other high-level details (like whether it is an associated +/// type or method, and whether it is public). This allows other +/// passes to find the impl they want without loading the ID (which +/// means fewer edges in the incremental compilation graph). +#[derive(Debug, HashStable_Generic)] +pub struct ForeignItemRef<'hir> { + pub id: ForeignItemId, + #[stable_hasher(project(name))] + pub ident: Ident, + pub span: Span, + pub vis: Visibility<'hir>, +} + #[derive(Debug, HashStable_Generic)] pub struct ForeignItem<'hir> { #[stable_hasher(project(name))] diff --git a/compiler/rustc_hir/src/intravisit.rs b/compiler/rustc_hir/src/intravisit.rs index 35615af0fc7..3e8fc689acf 100644 --- a/compiler/rustc_hir/src/intravisit.rs +++ b/compiler/rustc_hir/src/intravisit.rs @@ -64,6 +64,10 @@ where fn visit_impl_item(&mut self, impl_item: &'hir ImplItem<'hir>) { self.visitor.visit_impl_item(impl_item); } + + fn visit_foreign_item(&mut self, foreign_item: &'hir ForeignItem<'hir>) { + self.visitor.visit_foreign_item(foreign_item); + } } pub trait IntoVisitor<'hir> { @@ -88,6 +92,10 @@ where fn visit_impl_item(&self, impl_item: &'hir ImplItem<'hir>) { self.0.into_visitor().visit_impl_item(impl_item); } + + fn visit_foreign_item(&self, foreign_item: &'hir ForeignItem<'hir>) { + self.0.into_visitor().visit_foreign_item(foreign_item); + } } #[derive(Copy, Clone)] @@ -128,6 +136,7 @@ pub trait Map<'hir> { fn item(&self, id: HirId) -> &'hir Item<'hir>; fn trait_item(&self, id: TraitItemId) -> &'hir TraitItem<'hir>; fn impl_item(&self, id: ImplItemId) -> &'hir ImplItem<'hir>; + fn foreign_item(&self, id: ForeignItemId) -> &'hir ForeignItem<'hir>; } /// An erased version of `Map<'hir>`, using dynamic dispatch. @@ -150,6 +159,9 @@ impl<'hir> Map<'hir> for ErasedMap<'hir> { fn impl_item(&self, id: ImplItemId) -> &'hir ImplItem<'hir> { self.0.impl_item(id) } + fn foreign_item(&self, id: ForeignItemId) -> &'hir ForeignItem<'hir> { + self.0.foreign_item(id) + } } /// Specifies what nested things a visitor wants to visit. The most @@ -277,6 +289,14 @@ pub trait Visitor<'v>: Sized { walk_list!(self, visit_impl_item, opt_item); } + /// Like `visit_nested_item()`, but for foreign items. See + /// `visit_nested_item()` for advice on when to override this + /// method. + fn visit_nested_foreign_item(&mut self, id: ForeignItemId) { + let opt_item = self.nested_visit_map().inter().map(|map| map.foreign_item(id)); + walk_list!(self, visit_foreign_item, opt_item); + } + /// Invoked to visit the body of a function, method or closure. Like /// visit_nested_item, does nothing by default unless you override /// `nested_visit_map` to return other than `None`, in which case it will walk @@ -378,6 +398,9 @@ pub trait Visitor<'v>: Sized { fn visit_impl_item(&mut self, ii: &'v ImplItem<'v>) { walk_impl_item(self, ii) } + fn visit_foreign_item_ref(&mut self, ii: &'v ForeignItemRef<'v>) { + walk_foreign_item_ref(self, ii) + } fn visit_impl_item_ref(&mut self, ii: &'v ImplItemRef<'v>) { walk_impl_item_ref(self, ii) } @@ -566,9 +589,9 @@ pub fn walk_item<'v, V: Visitor<'v>>(visitor: &mut V, item: &'v Item<'v>) { // `visit_mod()` takes care of visiting the `Item`'s `HirId`. visitor.visit_mod(module, item.span, item.hir_id) } - ItemKind::ForeignMod(ref foreign_module) => { + ItemKind::ForeignMod { abi: _, items } => { visitor.visit_id(item.hir_id); - walk_list!(visitor, visit_foreign_item, foreign_module.items); + walk_list!(visitor, visit_foreign_item_ref, items); } ItemKind::GlobalAsm(_) => { visitor.visit_id(item.hir_id); @@ -1012,6 +1035,17 @@ pub fn walk_impl_item<'v, V: Visitor<'v>>(visitor: &mut V, impl_item: &'v ImplIt } } +pub fn walk_foreign_item_ref<'v, V: Visitor<'v>>( + visitor: &mut V, + foreign_item_ref: &'v ForeignItemRef<'v>, +) { + // N.B., deliberately force a compilation error if/when new fields are added. + let ForeignItemRef { id, ident, span: _, ref vis } = *foreign_item_ref; + visitor.visit_nested_foreign_item(id); + visitor.visit_ident(ident); + visitor.visit_vis(vis); +} + pub fn walk_impl_item_ref<'v, V: Visitor<'v>>(visitor: &mut V, impl_item_ref: &'v ImplItemRef<'v>) { // N.B., deliberately force a compilation error if/when new fields are added. let ImplItemRef { id, ident, ref kind, span: _, ref vis, ref defaultness } = *impl_item_ref; diff --git a/compiler/rustc_hir/src/itemlikevisit.rs b/compiler/rustc_hir/src/itemlikevisit.rs index 369cd49621b..0db562f91a6 100644 --- a/compiler/rustc_hir/src/itemlikevisit.rs +++ b/compiler/rustc_hir/src/itemlikevisit.rs @@ -1,4 +1,4 @@ -use super::{ImplItem, Item, TraitItem}; +use super::{ForeignItem, ImplItem, Item, TraitItem}; /// The "item-like visitor" defines only the top-level methods /// that can be invoked by `Crate::visit_all_item_likes()`. Whether @@ -47,6 +47,7 @@ pub trait ItemLikeVisitor<'hir> { fn visit_item(&mut self, item: &'hir Item<'hir>); fn visit_trait_item(&mut self, trait_item: &'hir TraitItem<'hir>); fn visit_impl_item(&mut self, impl_item: &'hir ImplItem<'hir>); + fn visit_foreign_item(&mut self, foreign_item: &'hir ForeignItem<'hir>); } /// A parallel variant of `ItemLikeVisitor`. @@ -54,4 +55,5 @@ pub trait ParItemLikeVisitor<'hir> { fn visit_item(&self, item: &'hir Item<'hir>); fn visit_trait_item(&self, trait_item: &'hir TraitItem<'hir>); fn visit_impl_item(&self, impl_item: &'hir ImplItem<'hir>); + fn visit_foreign_item(&self, foreign_item: &'hir ForeignItem<'hir>); } diff --git a/compiler/rustc_hir/src/stable_hash_impls.rs b/compiler/rustc_hir/src/stable_hash_impls.rs index 1d3f44a0899..439fb88039b 100644 --- a/compiler/rustc_hir/src/stable_hash_impls.rs +++ b/compiler/rustc_hir/src/stable_hash_impls.rs @@ -1,8 +1,8 @@ use rustc_data_structures::stable_hasher::{HashStable, StableHasher, ToStableHashKey}; use crate::hir::{ - BodyId, Expr, ImplItem, ImplItemId, Item, ItemId, Mod, TraitItem, TraitItemId, Ty, - VisibilityKind, + BodyId, Expr, ForeignItemId, ImplItem, ImplItemId, Item, ItemId, Mod, TraitItem, TraitItemId, + Ty, VisibilityKind, }; use crate::hir_id::{HirId, ItemLocalId}; use rustc_span::def_id::{DefPathHash, LocalDefId}; @@ -52,6 +52,15 @@ impl<HirCtx: crate::HashStableContext> ToStableHashKey<HirCtx> for ImplItemId { } } +impl<HirCtx: crate::HashStableContext> ToStableHashKey<HirCtx> for ForeignItemId { + type KeyType = (DefPathHash, ItemLocalId); + + #[inline] + fn to_stable_hash_key(&self, hcx: &HirCtx) -> (DefPathHash, ItemLocalId) { + self.hir_id.to_stable_hash_key(hcx) + } +} + impl<HirCtx: crate::HashStableContext> HashStable<HirCtx> for HirId { fn hash_stable(&self, hcx: &mut HirCtx, hasher: &mut StableHasher) { hcx.hash_hir_id(*self, hasher) @@ -77,6 +86,12 @@ impl<HirCtx: crate::HashStableContext> HashStable<HirCtx> for ItemId { } } +impl<HirCtx: crate::HashStableContext> HashStable<HirCtx> for ForeignItemId { + fn hash_stable(&self, hcx: &mut HirCtx, hasher: &mut StableHasher) { + hcx.hash_reference_to_item(self.hir_id, hasher) + } +} + impl<HirCtx: crate::HashStableContext> HashStable<HirCtx> for ImplItemId { fn hash_stable(&self, hcx: &mut HirCtx, hasher: &mut StableHasher) { hcx.hash_reference_to_item(self.hir_id, hasher) diff --git a/compiler/rustc_hir/src/target.rs b/compiler/rustc_hir/src/target.rs index fd6a312ef3a..b870e4c6ead 100644 --- a/compiler/rustc_hir/src/target.rs +++ b/compiler/rustc_hir/src/target.rs @@ -91,7 +91,7 @@ impl Target { ItemKind::Const(..) => Target::Const, ItemKind::Fn(..) => Target::Fn, ItemKind::Mod(..) => Target::Mod, - ItemKind::ForeignMod(..) => Target::ForeignMod, + ItemKind::ForeignMod { .. } => Target::ForeignMod, ItemKind::GlobalAsm(..) => Target::GlobalAsm, ItemKind::TyAlias(..) => Target::TyAlias, ItemKind::OpaqueTy(..) => Target::OpaqueTy, diff --git a/compiler/rustc_hir_pretty/src/lib.rs b/compiler/rustc_hir_pretty/src/lib.rs index f7018ae62aa..25b09d76295 100644 --- a/compiler/rustc_hir_pretty/src/lib.rs +++ b/compiler/rustc_hir_pretty/src/lib.rs @@ -36,6 +36,7 @@ pub enum Nested { Item(hir::ItemId), TraitItem(hir::TraitItemId), ImplItem(hir::ImplItemId), + ForeignItem(hir::ForeignItemId), Body(hir::BodyId), BodyParamPat(hir::BodyId, usize), } @@ -56,6 +57,7 @@ impl PpAnn for hir::Crate<'_> { Nested::Item(id) => state.print_item(self.item(id.id)), Nested::TraitItem(id) => state.print_trait_item(self.trait_item(id)), Nested::ImplItem(id) => state.print_impl_item(self.impl_item(id)), + Nested::ForeignItem(id) => state.print_foreign_item(self.foreign_item(id)), Nested::Body(id) => state.print_expr(&self.body(id).value), Nested::BodyParamPat(id, i) => state.print_pat(&self.body(id).params[i].pat), } @@ -70,6 +72,7 @@ impl PpAnn for &dyn rustc_hir::intravisit::Map<'_> { Nested::Item(id) => state.print_item(self.item(id.id)), Nested::TraitItem(id) => state.print_trait_item(self.trait_item(id)), Nested::ImplItem(id) => state.print_impl_item(self.impl_item(id)), + Nested::ForeignItem(id) => state.print_foreign_item(self.foreign_item(id)), Nested::Body(id) => state.print_expr(&self.body(id).value), Nested::BodyParamPat(id, i) => state.print_pat(&self.body(id).params[i].pat), } @@ -349,13 +352,6 @@ impl<'a> State<'a> { } } - pub fn print_foreign_mod(&mut self, nmod: &hir::ForeignMod<'_>, attrs: &[ast::Attribute]) { - self.print_inner_attributes(attrs); - for item in nmod.items { - self.print_foreign_item(item); - } - } - pub fn print_opt_lifetime(&mut self, lifetime: &hir::Lifetime) { if !lifetime.is_elided() { self.print_lifetime(lifetime); @@ -644,11 +640,14 @@ impl<'a> State<'a> { self.print_mod(_mod, &item.attrs); self.bclose(item.span); } - hir::ItemKind::ForeignMod(ref nmod) => { + hir::ItemKind::ForeignMod { abi, items } => { self.head("extern"); - self.word_nbsp(nmod.abi.to_string()); + self.word_nbsp(abi.to_string()); self.bopen(); - self.print_foreign_mod(nmod, &item.attrs); + self.print_inner_attributes(item.attrs); + for item in items { + self.ann.nested(self, Nested::ForeignItem(item.id)); + } self.bclose(item.span); } hir::ItemKind::GlobalAsm(ref ga) => { diff --git a/compiler/rustc_incremental/src/persist/dirty_clean.rs b/compiler/rustc_incremental/src/persist/dirty_clean.rs index d55813f4cc5..e1c60050d94 100644 --- a/compiler/rustc_incremental/src/persist/dirty_clean.rs +++ b/compiler/rustc_incremental/src/persist/dirty_clean.rs @@ -280,7 +280,7 @@ impl DirtyCleanVisitor<'tcx> { HirItem::Mod(..) => ("ItemMod", LABELS_HIR_ONLY), // // An external module - HirItem::ForeignMod(..) => ("ItemForeignMod", LABELS_HIR_ONLY), + HirItem::ForeignMod { .. } => ("ItemForeignMod", LABELS_HIR_ONLY), // Module-level inline assembly (from global_asm!) HirItem::GlobalAsm(..) => ("ItemGlobalAsm", LABELS_HIR_ONLY), @@ -460,6 +460,10 @@ impl ItemLikeVisitor<'tcx> for DirtyCleanVisitor<'tcx> { fn visit_impl_item(&mut self, item: &hir::ImplItem<'_>) { self.check_item(item.hir_id, item.span); } + + fn visit_foreign_item(&mut self, item: &hir::ForeignItem<'_>) { + self.check_item(item.hir_id, item.span); + } } /// Given a `#[rustc_dirty]` or `#[rustc_clean]` attribute, scan diff --git a/compiler/rustc_incremental/src/persist/load.rs b/compiler/rustc_incremental/src/persist/load.rs index 578c045a2b4..201f381f889 100644 --- a/compiler/rustc_incremental/src/persist/load.rs +++ b/compiler/rustc_incremental/src/persist/load.rs @@ -199,9 +199,14 @@ pub fn load_dep_graph(sess: &Session) -> DepGraphFuture { })) } -pub fn load_query_result_cache(sess: &Session) -> OnDiskCache<'_> { +/// Attempts to load the query result cache from disk +/// +/// If we are not in incremental compilation mode, returns `None`. +/// Otherwise, tries to load the query result cache from disk, +/// creating an empty cache if it could not be loaded. +pub fn load_query_result_cache(sess: &Session) -> Option<OnDiskCache<'_>> { if sess.opts.incremental.is_none() { - return OnDiskCache::new_empty(sess.source_map()); + return None; } let _prof_timer = sess.prof.generic_activity("incr_comp_load_query_result_cache"); @@ -211,7 +216,9 @@ pub fn load_query_result_cache(sess: &Session) -> OnDiskCache<'_> { &query_cache_path(sess), sess.is_nightly_build(), ) { - LoadResult::Ok { data: (bytes, start_pos) } => OnDiskCache::new(sess, bytes, start_pos), - _ => OnDiskCache::new_empty(sess.source_map()), + LoadResult::Ok { data: (bytes, start_pos) } => { + Some(OnDiskCache::new(sess, bytes, start_pos)) + } + _ => Some(OnDiskCache::new_empty(sess.source_map())), } } diff --git a/compiler/rustc_infer/src/infer/error_reporting/need_type_info.rs b/compiler/rustc_infer/src/infer/error_reporting/need_type_info.rs index fd8f46a6926..373f0a602c0 100644 --- a/compiler/rustc_infer/src/infer/error_reporting/need_type_info.rs +++ b/compiler/rustc_infer/src/infer/error_reporting/need_type_info.rs @@ -124,6 +124,11 @@ impl<'a, 'tcx> Visitor<'tcx> for FindHirNodeVisitor<'a, 'tcx> { return; } } + + // FIXME(const_generics): Currently, any uninferred `const` generics arguments + // are handled specially, but instead they should be handled in `annotate_method_call`, + // which currently doesn't work because this evaluates to `false` for const arguments. + // See https://github.com/rust-lang/rust/pull/77758 for more details. if self.node_ty_contains_target(expr.hir_id).is_some() { match expr.kind { ExprKind::Closure(..) => self.found_closure = Some(&expr), @@ -345,11 +350,6 @@ impl<'a, 'tcx> InferCtxt<'a, 'tcx> { ) -> DiagnosticBuilder<'tcx> { let arg = self.resolve_vars_if_possible(arg); let arg_data = self.extract_inference_diagnostics_data(arg, None); - let kind_str = match arg.unpack() { - GenericArgKind::Type(_) => "type", - GenericArgKind::Const(_) => "the value", - GenericArgKind::Lifetime(_) => bug!("unexpected lifetime"), - }; let mut local_visitor = FindHirNodeVisitor::new(&self, arg, span); let ty_to_string = |ty: Ty<'tcx>| -> String { @@ -618,6 +618,28 @@ impl<'a, 'tcx> InferCtxt<'a, 'tcx> { .any(|span_label| span_label.label.is_some() && span_label.span == span) && local_visitor.found_arg_pattern.is_none() { + let (kind_str, const_value) = match arg.unpack() { + GenericArgKind::Type(_) => ("type", None), + GenericArgKind::Const(_) => ("the value", Some(())), + GenericArgKind::Lifetime(_) => bug!("unexpected lifetime"), + }; + + // FIXME(const_generics): we would like to handle const arguments + // as part of the normal diagnostics flow below, but there appear to + // be subtleties in doing so, so for now we special-case const args + // here. + if let Some(suggestion) = const_value + .and_then(|_| arg_data.parent_name.as_ref()) + .map(|parent| format!("{}::<{}>", parent, arg_data.name)) + { + err.span_suggestion_verbose( + span, + "consider specifying the const argument", + suggestion, + Applicability::MaybeIncorrect, + ); + } + // Avoid multiple labels pointing at `span`. err.span_label( span, diff --git a/compiler/rustc_interface/src/interface.rs b/compiler/rustc_interface/src/interface.rs index 73a51ad477b..11dd6ec32c0 100644 --- a/compiler/rustc_interface/src/interface.rs +++ b/compiler/rustc_interface/src/interface.rs @@ -56,6 +56,9 @@ impl Compiler { pub fn output_file(&self) -> &Option<PathBuf> { &self.output_file } + pub fn register_lints(&self) -> &Option<Box<dyn Fn(&Session, &mut LintStore) + Send + Sync>> { + &self.register_lints + } pub fn build_output_filenames( &self, sess: &Session, diff --git a/compiler/rustc_interface/src/passes.rs b/compiler/rustc_interface/src/passes.rs index 5fd560d7eff..1f820024f77 100644 --- a/compiler/rustc_interface/src/passes.rs +++ b/compiler/rustc_interface/src/passes.rs @@ -816,6 +816,7 @@ fn analysis(tcx: TyCtxt<'_>, cnum: CrateNum) -> Result<()> { let local_def_id = tcx.hir().local_def_id(module); tcx.ensure().check_mod_loops(local_def_id); tcx.ensure().check_mod_attrs(local_def_id); + tcx.ensure().check_mod_naked_functions(local_def_id); tcx.ensure().check_mod_unstable_api_usage(local_def_id); tcx.ensure().check_mod_const_bodies(local_def_id); }); diff --git a/compiler/rustc_interface/src/proc_macro_decls.rs b/compiler/rustc_interface/src/proc_macro_decls.rs index d56115fd6ac..de08a4c8242 100644 --- a/compiler/rustc_interface/src/proc_macro_decls.rs +++ b/compiler/rustc_interface/src/proc_macro_decls.rs @@ -33,6 +33,8 @@ impl<'v> ItemLikeVisitor<'v> for Finder<'_> { fn visit_trait_item(&mut self, _trait_item: &hir::TraitItem<'_>) {} fn visit_impl_item(&mut self, _impl_item: &hir::ImplItem<'_>) {} + + fn visit_foreign_item(&mut self, _foreign_item: &hir::ForeignItem<'_>) {} } pub(crate) fn provide(providers: &mut Providers) { diff --git a/compiler/rustc_interface/src/tests.rs b/compiler/rustc_interface/src/tests.rs index 92262050b8c..2273266a3ff 100644 --- a/compiler/rustc_interface/src/tests.rs +++ b/compiler/rustc_interface/src/tests.rs @@ -498,7 +498,6 @@ fn test_debugging_options_tracking_hash() { untracked!(no_parallel_llvm, true); untracked!(parse_only, true); untracked!(perf_stats, true); - untracked!(polonius, true); // `pre_link_arg` is omitted because it just forwards to `pre_link_args`. untracked!(pre_link_args, vec![String::from("abc"), String::from("def")]); untracked!(print_link_args, true); @@ -572,6 +571,7 @@ fn test_debugging_options_tracking_hash() { tracked!(osx_rpath_install_name, true); tracked!(panic_abort_tests, true); tracked!(plt, Some(true)); + tracked!(polonius, true); tracked!(precise_enum_drop_elaboration, false); tracked!(print_fuel, Some("abc".to_string())); tracked!(profile, true); diff --git a/compiler/rustc_interface/src/util.rs b/compiler/rustc_interface/src/util.rs index 20a7b47313e..f34990a1a10 100644 --- a/compiler/rustc_interface/src/util.rs +++ b/compiler/rustc_interface/src/util.rs @@ -1,6 +1,5 @@ use rustc_ast::mut_visit::{visit_clobber, MutVisitor, *}; use rustc_ast::ptr::P; -use rustc_ast::util::lev_distance::find_best_match_for_name; use rustc_ast::{self as ast, AttrVec, BlockCheckMode}; use rustc_codegen_ssa::traits::CodegenBackend; use rustc_data_structures::fingerprint::Fingerprint; @@ -20,6 +19,7 @@ use rustc_session::parse::CrateConfig; use rustc_session::CrateDisambiguator; use rustc_session::{early_error, filesearch, output, DiagnosticOutput, Session}; use rustc_span::edition::Edition; +use rustc_span::lev_distance::find_best_match_for_name; use rustc_span::source_map::FileLoader; use rustc_span::symbol::{sym, Symbol}; use smallvec::SmallVec; @@ -512,8 +512,11 @@ pub(crate) fn check_attr_crate_type( if let ast::MetaItemKind::NameValue(spanned) = a.meta().unwrap().kind { let span = spanned.span; - let lev_candidate = - find_best_match_for_name(CRATE_TYPES.iter().map(|(k, _)| k), n, None); + let lev_candidate = find_best_match_for_name( + &CRATE_TYPES.iter().map(|(k, _)| *k).collect::<Vec<_>>(), + n, + None, + ); if let Some(candidate) = lev_candidate { lint_buffer.buffer_lint_with_diagnostic( lint::builtin::UNKNOWN_CRATE_TYPES, @@ -807,7 +810,6 @@ impl<'a> MutVisitor for ReplaceBodyWithLoop<'a, '_> { id: resolver.next_node_id(), kind: ast::StmtKind::Expr(expr), span: rustc_span::DUMMY_SP, - tokens: None, } } @@ -824,7 +826,6 @@ impl<'a> MutVisitor for ReplaceBodyWithLoop<'a, '_> { id: self.resolver.next_node_id(), span: rustc_span::DUMMY_SP, kind: ast::StmtKind::Expr(loop_expr), - tokens: None, }; if self.within_static_or_const { diff --git a/compiler/rustc_lint/src/builtin.rs b/compiler/rustc_lint/src/builtin.rs index c65cf65b1c7..676c85e4afd 100644 --- a/compiler/rustc_lint/src/builtin.rs +++ b/compiler/rustc_lint/src/builtin.rs @@ -2345,7 +2345,7 @@ impl<'tcx> LateLintPass<'tcx> for InvalidValue { enum InitKind { Zeroed, Uninit, - }; + } /// Information about why a type cannot be initialized this way. /// Contains an error message and optionally a span to point at. diff --git a/compiler/rustc_lint/src/context.rs b/compiler/rustc_lint/src/context.rs index 4cfeb0d968b..16563d21ff1 100644 --- a/compiler/rustc_lint/src/context.rs +++ b/compiler/rustc_lint/src/context.rs @@ -19,7 +19,6 @@ use self::TargetLint::*; use crate::levels::LintLevelsBuilder; use crate::passes::{EarlyLintPassObject, LateLintPassObject}; use rustc_ast as ast; -use rustc_ast::util::lev_distance::find_best_match_for_name; use rustc_data_structures::fx::FxHashMap; use rustc_data_structures::sync; use rustc_errors::{add_elided_lifetime_in_path_suggestion, struct_span_err, Applicability}; @@ -37,6 +36,7 @@ use rustc_session::lint::BuiltinLintDiagnostics; use rustc_session::lint::{FutureIncompatibleInfo, Level, Lint, LintBuffer, LintId}; use rustc_session::Session; use rustc_session::SessionLintStore; +use rustc_span::lev_distance::find_best_match_for_name; use rustc_span::{symbol::Symbol, MultiSpan, Span, DUMMY_SP}; use rustc_target::abi::LayoutOf; @@ -411,7 +411,7 @@ impl LintStore { self.by_name.keys().map(|name| Symbol::intern(&name)).collect::<Vec<_>>(); let suggestion = find_best_match_for_name( - symbols.iter(), + &symbols, Symbol::intern(&lint_name.to_lowercase()), None, ); diff --git a/compiler/rustc_lint/src/redundant_semicolon.rs b/compiler/rustc_lint/src/redundant_semicolon.rs index 84cc7b68d4c..428198cae89 100644 --- a/compiler/rustc_lint/src/redundant_semicolon.rs +++ b/compiler/rustc_lint/src/redundant_semicolon.rs @@ -28,25 +28,40 @@ declare_lint_pass!(RedundantSemicolons => [REDUNDANT_SEMICOLONS]); impl EarlyLintPass for RedundantSemicolons { fn check_block(&mut self, cx: &EarlyContext<'_>, block: &Block) { + let mut after_item_stmt = false; let mut seq = None; for stmt in block.stmts.iter() { match (&stmt.kind, &mut seq) { (StmtKind::Empty, None) => seq = Some((stmt.span, false)), (StmtKind::Empty, Some(seq)) => *seq = (seq.0.to(stmt.span), true), - (_, seq) => maybe_lint_redundant_semis(cx, seq), + (_, seq) => { + maybe_lint_redundant_semis(cx, seq, after_item_stmt); + after_item_stmt = matches!(stmt.kind, StmtKind::Item(_)); + } } } - maybe_lint_redundant_semis(cx, &mut seq); + maybe_lint_redundant_semis(cx, &mut seq, after_item_stmt); } } -fn maybe_lint_redundant_semis(cx: &EarlyContext<'_>, seq: &mut Option<(Span, bool)>) { +fn maybe_lint_redundant_semis( + cx: &EarlyContext<'_>, + seq: &mut Option<(Span, bool)>, + after_item_stmt: bool, +) { if let Some((span, multiple)) = seq.take() { // FIXME: Find a better way of ignoring the trailing // semicolon from macro expansion if span == rustc_span::DUMMY_SP { return; } + + // FIXME: Lint on semicolons after item statements + // once doing so doesn't break bootstrapping + if after_item_stmt { + return; + } + cx.struct_span_lint(REDUNDANT_SEMICOLONS, span, |lint| { let (msg, rem) = if multiple { ("unnecessary trailing semicolons", "remove these semicolons") diff --git a/compiler/rustc_lint/src/types.rs b/compiler/rustc_lint/src/types.rs index 38c71e6e925..9ad9d53cd0d 100644 --- a/compiler/rustc_lint/src/types.rs +++ b/compiler/rustc_lint/src/types.rs @@ -1131,7 +1131,7 @@ impl<'a, 'tcx> ImproperCTypesVisitor<'a, 'tcx> { fn check_for_opaque_ty(&mut self, sp: Span, ty: Ty<'tcx>) -> bool { struct ProhibitOpaqueTypes<'a, 'tcx> { cx: &'a LateContext<'tcx>, - }; + } impl<'a, 'tcx> ty::fold::TypeVisitor<'tcx> for ProhibitOpaqueTypes<'a, 'tcx> { type BreakTy = Ty<'tcx>; diff --git a/compiler/rustc_llvm/llvm-wrapper/CoverageMappingWrapper.cpp b/compiler/rustc_llvm/llvm-wrapper/CoverageMappingWrapper.cpp index 2b1143a4ecf..25badc3f4e1 100644 --- a/compiler/rustc_llvm/llvm-wrapper/CoverageMappingWrapper.cpp +++ b/compiler/rustc_llvm/llvm-wrapper/CoverageMappingWrapper.cpp @@ -3,7 +3,6 @@ #include "llvm/ProfileData/Coverage/CoverageMappingWriter.h" #include "llvm/ProfileData/InstrProf.h" #include "llvm/ADT/ArrayRef.h" -#include "llvm/Support/LEB128.h" #include <iostream> @@ -13,15 +12,14 @@ extern "C" void LLVMRustCoverageWriteFilenamesSectionToBuffer( const char* const Filenames[], size_t FilenamesLen, RustStringRef BufferOut) { - // LLVM 11's CoverageFilenamesSectionWriter uses its new `Version4` format, - // so we're manually writing the `Version3` format ourselves. - RawRustStringOstream OS(BufferOut); - encodeULEB128(FilenamesLen, OS); + SmallVector<StringRef,32> FilenameRefs; for (size_t i = 0; i < FilenamesLen; i++) { - StringRef Filename(Filenames[i]); - encodeULEB128(Filename.size(), OS); - OS << Filename; + FilenameRefs.push_back(StringRef(Filenames[i])); } + auto FilenamesWriter = coverage::CoverageFilenamesSectionWriter( + makeArrayRef(FilenameRefs)); + RawRustStringOstream OS(BufferOut); + FilenamesWriter.write(OS); } extern "C" void LLVMRustCoverageWriteMappingToBuffer( @@ -45,20 +43,40 @@ extern "C" LLVMValueRef LLVMRustCoverageCreatePGOFuncNameVar(LLVMValueRef F, con return wrap(createPGOFuncNameVar(*cast<Function>(unwrap(F)), FuncNameRef)); } -extern "C" uint64_t LLVMRustCoverageComputeHash(const char *Name) { - StringRef NameRef(Name); - return IndexedInstrProf::ComputeHash(NameRef); +extern "C" uint64_t LLVMRustCoverageHashCString(const char *StrVal) { + StringRef StrRef(StrVal); + return IndexedInstrProf::ComputeHash(StrRef); +} + +extern "C" uint64_t LLVMRustCoverageHashByteArray( + const char *Bytes, + unsigned NumBytes) { + StringRef StrRef(Bytes, NumBytes); + return IndexedInstrProf::ComputeHash(StrRef); } -extern "C" void LLVMRustCoverageWriteSectionNameToString(LLVMModuleRef M, - RustStringRef Str) { +static void WriteSectionNameToString(LLVMModuleRef M, + InstrProfSectKind SK, + RustStringRef Str) { Triple TargetTriple(unwrap(M)->getTargetTriple()); - auto name = getInstrProfSectionName(IPSK_covmap, - TargetTriple.getObjectFormat()); + auto name = getInstrProfSectionName(SK, TargetTriple.getObjectFormat()); RawRustStringOstream OS(Str); OS << name; } +extern "C" void LLVMRustCoverageWriteMapSectionNameToString(LLVMModuleRef M, + RustStringRef Str) { + WriteSectionNameToString(M, IPSK_covmap, Str); +} + +extern "C" void LLVMRustCoverageWriteFuncSectionNameToString(LLVMModuleRef M, + RustStringRef Str) { +#if LLVM_VERSION_GE(11, 0) + WriteSectionNameToString(M, IPSK_covfun, Str); +// else do nothing; the `Version` check will abort codegen on the Rust side +#endif +} + extern "C" void LLVMRustCoverageWriteMappingVarNameToString(RustStringRef Str) { auto name = getCoverageMappingVarName(); RawRustStringOstream OS(Str); @@ -66,5 +84,9 @@ extern "C" void LLVMRustCoverageWriteMappingVarNameToString(RustStringRef Str) { } extern "C" uint32_t LLVMRustCoverageMappingVersion() { +#if LLVM_VERSION_GE(11, 0) + return coverage::CovMapVersion::Version4; +#else return coverage::CovMapVersion::Version3; +#endif } diff --git a/compiler/rustc_llvm/llvm-wrapper/RustWrapper.cpp b/compiler/rustc_llvm/llvm-wrapper/RustWrapper.cpp index 9b0c176b692..e17f933932e 100644 --- a/compiler/rustc_llvm/llvm-wrapper/RustWrapper.cpp +++ b/compiler/rustc_llvm/llvm-wrapper/RustWrapper.cpp @@ -1462,7 +1462,7 @@ extern "C" void LLVMRustSetComdat(LLVMModuleRef M, LLVMValueRef V, const char *Name, size_t NameLen) { Triple TargetTriple(unwrap(M)->getTargetTriple()); GlobalObject *GV = unwrap<GlobalObject>(V); - if (!TargetTriple.isOSBinFormatMachO()) { + if (TargetTriple.supportsCOMDAT()) { StringRef NameRef(Name, NameLen); GV->setComdat(unwrap(M)->getOrInsertComdat(NameRef)); } diff --git a/compiler/rustc_macros/src/query.rs b/compiler/rustc_macros/src/query.rs index fd859196369..12990ae2d94 100644 --- a/compiler/rustc_macros/src/query.rs +++ b/compiler/rustc_macros/src/query.rs @@ -353,7 +353,7 @@ fn add_query_description_impl( tcx: TyCtxt<'tcx>, id: SerializedDepNodeIndex ) -> Option<Self::Value> { - tcx.queries.on_disk_cache.try_load_query_result(tcx, id) + tcx.queries.on_disk_cache.as_ref().and_then(|c| c.try_load_query_result(tcx, id)) } } }; diff --git a/compiler/rustc_metadata/src/foreign_modules.rs b/compiler/rustc_metadata/src/foreign_modules.rs index 8675197656a..4785b6c379c 100644 --- a/compiler/rustc_metadata/src/foreign_modules.rs +++ b/compiler/rustc_metadata/src/foreign_modules.rs @@ -16,13 +16,13 @@ struct Collector<'tcx> { impl ItemLikeVisitor<'tcx> for Collector<'tcx> { fn visit_item(&mut self, it: &'tcx hir::Item<'tcx>) { - let fm = match it.kind { - hir::ItemKind::ForeignMod(ref fm) => fm, + let items = match it.kind { + hir::ItemKind::ForeignMod { items, .. } => items, _ => return, }; let foreign_items = - fm.items.iter().map(|it| self.tcx.hir().local_def_id(it.hir_id).to_def_id()).collect(); + items.iter().map(|it| self.tcx.hir().local_def_id(it.id.hir_id).to_def_id()).collect(); self.modules.push(ForeignModule { foreign_items, def_id: self.tcx.hir().local_def_id(it.hir_id).to_def_id(), @@ -31,4 +31,5 @@ impl ItemLikeVisitor<'tcx> for Collector<'tcx> { fn visit_trait_item(&mut self, _it: &'tcx hir::TraitItem<'tcx>) {} fn visit_impl_item(&mut self, _it: &'tcx hir::ImplItem<'tcx>) {} + fn visit_foreign_item(&mut self, _it: &'tcx hir::ForeignItem<'tcx>) {} } diff --git a/compiler/rustc_metadata/src/link_args.rs b/compiler/rustc_metadata/src/link_args.rs index d8f16796083..d088288c507 100644 --- a/compiler/rustc_metadata/src/link_args.rs +++ b/compiler/rustc_metadata/src/link_args.rs @@ -26,11 +26,11 @@ struct Collector<'tcx> { impl<'tcx> ItemLikeVisitor<'tcx> for Collector<'tcx> { fn visit_item(&mut self, it: &'tcx hir::Item<'tcx>) { - let fm = match it.kind { - hir::ItemKind::ForeignMod(ref fm) => fm, + let abi = match it.kind { + hir::ItemKind::ForeignMod { abi, .. } => abi, _ => return, }; - if fm.abi == Abi::Rust || fm.abi == Abi::RustIntrinsic || fm.abi == Abi::PlatformIntrinsic { + if abi == Abi::Rust || abi == Abi::RustIntrinsic || abi == Abi::PlatformIntrinsic { return; } @@ -45,6 +45,7 @@ impl<'tcx> ItemLikeVisitor<'tcx> for Collector<'tcx> { fn visit_trait_item(&mut self, _it: &'tcx hir::TraitItem<'tcx>) {} fn visit_impl_item(&mut self, _it: &'tcx hir::ImplItem<'tcx>) {} + fn visit_foreign_item(&mut self, _it: &'tcx hir::ForeignItem<'tcx>) {} } impl<'tcx> Collector<'tcx> { diff --git a/compiler/rustc_metadata/src/native_libs.rs b/compiler/rustc_metadata/src/native_libs.rs index 2f7c2c2c405..fe29f9d177f 100644 --- a/compiler/rustc_metadata/src/native_libs.rs +++ b/compiler/rustc_metadata/src/native_libs.rs @@ -33,12 +33,12 @@ struct Collector<'tcx> { impl ItemLikeVisitor<'tcx> for Collector<'tcx> { fn visit_item(&mut self, it: &'tcx hir::Item<'tcx>) { - let fm = match it.kind { - hir::ItemKind::ForeignMod(ref fm) => fm, + let abi = match it.kind { + hir::ItemKind::ForeignMod { abi, .. } => abi, _ => return, }; - if fm.abi == Abi::Rust || fm.abi == Abi::RustIntrinsic || fm.abi == Abi::PlatformIntrinsic { + if abi == Abi::Rust || abi == Abi::RustIntrinsic || abi == Abi::PlatformIntrinsic { return; } @@ -127,6 +127,7 @@ impl ItemLikeVisitor<'tcx> for Collector<'tcx> { fn visit_trait_item(&mut self, _it: &'tcx hir::TraitItem<'tcx>) {} fn visit_impl_item(&mut self, _it: &'tcx hir::ImplItem<'tcx>) {} + fn visit_foreign_item(&mut self, _it: &'tcx hir::ForeignItem<'tcx>) {} } impl Collector<'tcx> { diff --git a/compiler/rustc_metadata/src/rmeta/decoder.rs b/compiler/rustc_metadata/src/rmeta/decoder.rs index 19340dd51de..e82449f69fd 100644 --- a/compiler/rustc_metadata/src/rmeta/decoder.rs +++ b/compiler/rustc_metadata/src/rmeta/decoder.rs @@ -644,6 +644,7 @@ impl EntryKind { EntryKind::TraitAlias => DefKind::TraitAlias, EntryKind::Enum(..) => DefKind::Enum, EntryKind::MacroDef(_) => DefKind::Macro(MacroKind::Bang), + EntryKind::ProcMacro(kind) => DefKind::Macro(kind), EntryKind::ForeignType => DefKind::ForeignTy, EntryKind::Impl(_) => DefKind::Impl, EntryKind::Closure => DefKind::Closure, @@ -685,20 +686,11 @@ impl CrateRoot<'_> { } impl<'a, 'tcx> CrateMetadataRef<'a> { - fn is_proc_macro(&self, id: DefIndex) -> bool { - self.root - .proc_macro_data - .as_ref() - .and_then(|data| data.macros.decode(self).find(|x| *x == id)) - .is_some() - } - fn maybe_kind(&self, item_id: DefIndex) -> Option<EntryKind> { self.root.tables.kind.get(self, item_id).map(|k| k.decode(self)) } fn kind(&self, item_id: DefIndex) -> EntryKind { - assert!(!self.is_proc_macro(item_id)); self.maybe_kind(item_id).unwrap_or_else(|| { bug!( "CrateMetadata::kind({:?}): id not found, in crate {:?} with number {}", @@ -725,35 +717,24 @@ impl<'a, 'tcx> CrateMetadataRef<'a> { } fn item_ident(&self, item_index: DefIndex, sess: &Session) -> Ident { - if !self.is_proc_macro(item_index) { - let name = self - .def_key(item_index) - .disambiguated_data - .data - .get_opt_name() - .expect("no name in item_ident"); - let span = self - .root - .tables - .ident_span - .get(self, item_index) - .map(|data| data.decode((self, sess))) - .unwrap_or_else(|| panic!("Missing ident span for {:?} ({:?})", name, item_index)); - Ident::new(name, span) - } else { - Ident::new( - Symbol::intern(self.raw_proc_macro(item_index).name()), - self.get_span(item_index, sess), - ) - } + let name = self + .def_key(item_index) + .disambiguated_data + .data + .get_opt_name() + .expect("no name in item_ident"); + let span = self + .root + .tables + .ident_span + .get(self, item_index) + .map(|data| data.decode((self, sess))) + .unwrap_or_else(|| panic!("Missing ident span for {:?} ({:?})", name, item_index)); + Ident::new(name, span) } fn def_kind(&self, index: DefIndex) -> DefKind { - if !self.is_proc_macro(index) { - self.kind(index).def_kind() - } else { - DefKind::Macro(macro_kind(self.raw_proc_macro(index))) - } + self.kind(index).def_kind() } fn get_span(&self, index: DefIndex, sess: &Session) -> Span { @@ -956,10 +937,7 @@ impl<'a, 'tcx> CrateMetadataRef<'a> { } fn get_stability(&self, id: DefIndex) -> Option<attr::Stability> { - match self.is_proc_macro(id) { - true => self.root.proc_macro_data.as_ref().unwrap().stability, - false => self.root.tables.stability.get(self, id).map(|stab| stab.decode(self)), - } + self.root.tables.stability.get(self, id).map(|stab| stab.decode(self)) } fn get_const_stability(&self, id: DefIndex) -> Option<attr::ConstStability> { @@ -967,19 +945,11 @@ impl<'a, 'tcx> CrateMetadataRef<'a> { } fn get_deprecation(&self, id: DefIndex) -> Option<attr::Deprecation> { - self.root - .tables - .deprecation - .get(self, id) - .filter(|_| !self.is_proc_macro(id)) - .map(|depr| depr.decode(self)) + self.root.tables.deprecation.get(self, id).map(|depr| depr.decode(self)) } fn get_visibility(&self, id: DefIndex) -> ty::Visibility { - match self.is_proc_macro(id) { - true => ty::Visibility::Public, - false => self.root.tables.visibility.get(self, id).unwrap().decode(self), - } + self.root.tables.visibility.get(self, id).unwrap().decode(self) } fn get_impl_data(&self, id: DefIndex) -> ImplData { @@ -1191,7 +1161,7 @@ impl<'a, 'tcx> CrateMetadataRef<'a> { } fn is_item_mir_available(&self, id: DefIndex) -> bool { - !self.is_proc_macro(id) && self.root.tables.mir.get(self, id).is_some() + self.root.tables.mir.get(self, id).is_some() } fn module_expansion(&self, id: DefIndex, sess: &Session) -> ExpnId { @@ -1207,7 +1177,6 @@ impl<'a, 'tcx> CrateMetadataRef<'a> { .tables .mir .get(self, id) - .filter(|_| !self.is_proc_macro(id)) .unwrap_or_else(|| { bug!("get_optimized_mir: missing MIR for `{:?}`", self.local_def_id(id)) }) @@ -1223,7 +1192,6 @@ impl<'a, 'tcx> CrateMetadataRef<'a> { .tables .mir_abstract_consts .get(self, id) - .filter(|_| !self.is_proc_macro(id)) .map_or(Ok(None), |v| Ok(Some(v.decode((self, tcx))))) } @@ -1232,7 +1200,6 @@ impl<'a, 'tcx> CrateMetadataRef<'a> { .tables .unused_generic_params .get(self, id) - .filter(|_| !self.is_proc_macro(id)) .map(|params| params.decode(self)) .unwrap_or_default() } @@ -1242,7 +1209,6 @@ impl<'a, 'tcx> CrateMetadataRef<'a> { .tables .promoted_mir .get(self, id) - .filter(|_| !self.is_proc_macro(id)) .unwrap_or_else(|| { bug!("get_promoted_mir: missing MIR for `{:?}`", self.local_def_id(id)) }) @@ -1546,14 +1512,11 @@ impl<'a, 'tcx> CrateMetadataRef<'a> { #[inline] fn def_key(&self, index: DefIndex) -> DefKey { - *self.def_key_cache.lock().entry(index).or_insert_with(|| { - let mut key = self.root.tables.def_keys.get(self, index).unwrap().decode(self); - if self.is_proc_macro(index) { - let name = self.raw_proc_macro(index).name(); - key.disambiguated_data.data = DefPathData::MacroNs(Symbol::intern(name)); - } - key - }) + *self + .def_key_cache + .lock() + .entry(index) + .or_insert_with(|| self.root.tables.def_keys.get(self, index).unwrap().decode(self)) } // Returns the path leading to the thing with this `id`. diff --git a/compiler/rustc_metadata/src/rmeta/encoder.rs b/compiler/rustc_metadata/src/rmeta/encoder.rs index a7cf1079b8f..46dd0df65e0 100644 --- a/compiler/rustc_metadata/src/rmeta/encoder.rs +++ b/compiler/rustc_metadata/src/rmeta/encoder.rs @@ -9,6 +9,7 @@ use rustc_data_structures::sync::{join, Lrc}; use rustc_hir as hir; use rustc_hir::def::CtorKind; use rustc_hir::def_id::{CrateNum, DefId, DefIndex, LocalDefId, CRATE_DEF_INDEX, LOCAL_CRATE}; +use rustc_hir::definitions::DefPathData; use rustc_hir::intravisit::{self, NestedVisitorMap, Visitor}; use rustc_hir::itemlikevisit::{ItemLikeVisitor, ParItemLikeVisitor}; use rustc_hir::lang_items; @@ -27,7 +28,7 @@ use rustc_middle::ty::codec::TyEncoder; use rustc_middle::ty::{self, SymbolName, Ty, TyCtxt}; use rustc_serialize::{opaque, Encodable, Encoder}; use rustc_session::config::CrateType; -use rustc_span::hygiene::{ExpnDataEncodeMode, HygieneEncodeContext}; +use rustc_span::hygiene::{ExpnDataEncodeMode, HygieneEncodeContext, MacroKind}; use rustc_span::symbol::{sym, Ident, Symbol}; use rustc_span::{self, ExternalSource, FileName, SourceFile, Span, SyntaxContext}; use rustc_target::abi::VariantIdx; @@ -1225,7 +1226,7 @@ impl EncodeContext<'a, 'tcx> { hir::ItemKind::Mod(ref m) => { return self.encode_info_for_mod(item.hir_id, m, &item.attrs); } - hir::ItemKind::ForeignMod(_) => EntryKind::ForeignMod, + hir::ItemKind::ForeignMod { .. } => EntryKind::ForeignMod, hir::ItemKind::GlobalAsm(..) => EntryKind::GlobalAsm, hir::ItemKind::TyAlias(..) => EntryKind::Type, hir::ItemKind::OpaqueTy(..) => { @@ -1320,11 +1321,11 @@ impl EncodeContext<'a, 'tcx> { record!(self.tables.expn_that_defined[def_id] <- self.tcx.expansion_that_defined(def_id)); // FIXME(eddyb) there should be a nicer way to do this. match item.kind { - hir::ItemKind::ForeignMod(ref fm) => record!(self.tables.children[def_id] <- - fm.items + hir::ItemKind::ForeignMod { items, .. } => record!(self.tables.children[def_id] <- + items .iter() .map(|foreign_item| tcx.hir().local_def_id( - foreign_item.hir_id).local_def_index) + foreign_item.id.hir_id).local_def_index) ), hir::ItemKind::Enum(..) => record!(self.tables.children[def_id] <- self.tcx.adt_def(def_id).variants.iter().map(|v| { @@ -1539,12 +1540,41 @@ impl EncodeContext<'a, 'tcx> { // so we manually encode just the information that we need for proc_macro in &hir.krate().proc_macros { let id = proc_macro.owner.local_def_index; - let span = self.lazy(hir.span(*proc_macro)); + let mut name = hir.name(*proc_macro); + let span = hir.span(*proc_macro); // Proc-macros may have attributes like `#[allow_internal_unstable]`, // so downstream crates need access to them. - let attrs = self.lazy(hir.attrs(*proc_macro)); - self.tables.span.set(id, span); - self.tables.attributes.set(id, attrs); + let attrs = hir.attrs(*proc_macro); + let macro_kind = if tcx.sess.contains_name(attrs, sym::proc_macro) { + MacroKind::Bang + } else if tcx.sess.contains_name(attrs, sym::proc_macro_attribute) { + MacroKind::Attr + } else if let Some(attr) = tcx.sess.find_by_name(attrs, sym::proc_macro_derive) { + // This unwrap chain should have been checked by the proc-macro harness. + name = attr.meta_item_list().unwrap()[0] + .meta_item() + .unwrap() + .ident() + .unwrap() + .name; + MacroKind::Derive + } else { + bug!("Unknown proc-macro type for item {:?}", id); + }; + + let mut def_key = self.tcx.hir().def_key(proc_macro.owner); + def_key.disambiguated_data.data = DefPathData::MacroNs(name); + + let def_id = DefId::local(id); + record!(self.tables.kind[def_id] <- EntryKind::ProcMacro(macro_kind)); + record!(self.tables.attributes[def_id] <- attrs); + record!(self.tables.def_keys[def_id] <- def_key); + record!(self.tables.ident_span[def_id] <- span); + record!(self.tables.span[def_id] <- span); + record!(self.tables.visibility[def_id] <- ty::Visibility::Public); + if let Some(stability) = stability { + record!(self.tables.stability[def_id] <- stability); + } } Some(ProcMacroData { proc_macro_decls_static, stability, macros }) @@ -1836,7 +1866,7 @@ impl EncodeContext<'a, 'tcx> { | hir::ItemKind::Const(..) | hir::ItemKind::Fn(..) | hir::ItemKind::Mod(..) - | hir::ItemKind::ForeignMod(..) + | hir::ItemKind::ForeignMod { .. } | hir::ItemKind::GlobalAsm(..) | hir::ItemKind::ExternCrate(..) | hir::ItemKind::Use(..) @@ -1913,6 +1943,8 @@ impl<'tcx, 'v> ItemLikeVisitor<'v> for ImplVisitor<'tcx> { fn visit_impl_item(&mut self, _impl_item: &'v hir::ImplItem<'v>) { // handled in `visit_item` above } + + fn visit_foreign_item(&mut self, _foreign_item: &'v hir::ForeignItem<'v>) {} } /// Used to prefetch queries which will be needed later by metadata encoding. @@ -1977,6 +2009,11 @@ impl<'tcx, 'v> ParItemLikeVisitor<'v> for PrefetchVisitor<'tcx> { hir::ImplItemKind::TyAlias(..) => (), } } + + fn visit_foreign_item(&self, _foreign_item: &'v hir::ForeignItem<'v>) { + // This should be kept in sync with `encode_info_for_foreign_item`. + // Foreign items contain no MIR. + } } // NOTE(eddyb) The following comment was preserved for posterity, even diff --git a/compiler/rustc_metadata/src/rmeta/mod.rs b/compiler/rustc_metadata/src/rmeta/mod.rs index 2bd2019d3cd..53606178909 100644 --- a/compiler/rustc_metadata/src/rmeta/mod.rs +++ b/compiler/rustc_metadata/src/rmeta/mod.rs @@ -20,6 +20,7 @@ use rustc_serialize::opaque::Encoder; use rustc_session::config::SymbolManglingVersion; use rustc_session::CrateDisambiguator; use rustc_span::edition::Edition; +use rustc_span::hygiene::MacroKind; use rustc_span::symbol::{Ident, Symbol}; use rustc_span::{self, ExpnData, ExpnId, Span}; use rustc_target::spec::{PanicStrategy, TargetTriple}; @@ -336,6 +337,7 @@ enum EntryKind { ForeignFn(Lazy<FnData>), Mod(Lazy<ModData>), MacroDef(Lazy<MacroDef>), + ProcMacro(MacroKind), Closure, Generator(hir::GeneratorKind), Trait(Lazy<TraitData>), diff --git a/compiler/rustc_middle/src/dep_graph/mod.rs b/compiler/rustc_middle/src/dep_graph/mod.rs index 66975242798..a85b66b65da 100644 --- a/compiler/rustc_middle/src/dep_graph/mod.rs +++ b/compiler/rustc_middle/src/dep_graph/mod.rs @@ -164,11 +164,17 @@ impl<'tcx> DepContext for TyCtxt<'tcx> { } fn load_diagnostics(&self, prev_dep_node_index: SerializedDepNodeIndex) -> Vec<Diagnostic> { - self.queries.on_disk_cache.load_diagnostics(*self, prev_dep_node_index) + self.queries + .on_disk_cache + .as_ref() + .map(|c| c.load_diagnostics(*self, prev_dep_node_index)) + .unwrap_or_default() } fn store_diagnostics(&self, dep_node_index: DepNodeIndex, diagnostics: ThinVec<Diagnostic>) { - self.queries.on_disk_cache.store_diagnostics(dep_node_index, diagnostics) + if let Some(c) = self.queries.on_disk_cache.as_ref() { + c.store_diagnostics(dep_node_index, diagnostics) + } } fn store_diagnostics_for_anon_node( @@ -176,7 +182,9 @@ impl<'tcx> DepContext for TyCtxt<'tcx> { dep_node_index: DepNodeIndex, diagnostics: ThinVec<Diagnostic>, ) { - self.queries.on_disk_cache.store_diagnostics_for_anon_node(dep_node_index, diagnostics) + if let Some(c) = self.queries.on_disk_cache.as_ref() { + c.store_diagnostics_for_anon_node(dep_node_index, diagnostics) + } } fn profiler(&self) -> &SelfProfilerRef { diff --git a/compiler/rustc_middle/src/hir/map/collector.rs b/compiler/rustc_middle/src/hir/map/collector.rs index 516c9b6752b..912e9672c94 100644 --- a/compiler/rustc_middle/src/hir/map/collector.rs +++ b/compiler/rustc_middle/src/hir/map/collector.rs @@ -112,6 +112,7 @@ impl<'a, 'hir> NodeCollector<'a, 'hir> { items: _, trait_items: _, impl_items: _, + foreign_items: _, bodies: _, trait_impls: _, body_ids: _, @@ -319,6 +320,10 @@ impl<'a, 'hir> Visitor<'hir> for NodeCollector<'a, 'hir> { self.visit_impl_item(self.krate.impl_item(item_id)); } + fn visit_nested_foreign_item(&mut self, foreign_id: ForeignItemId) { + self.visit_foreign_item(self.krate.foreign_item(foreign_id)); + } + fn visit_nested_body(&mut self, id: BodyId) { self.visit_body(self.krate.body(id)); } @@ -351,11 +356,17 @@ impl<'a, 'hir> Visitor<'hir> for NodeCollector<'a, 'hir> { }); } - fn visit_foreign_item(&mut self, foreign_item: &'hir ForeignItem<'hir>) { - self.insert(foreign_item.span, foreign_item.hir_id, Node::ForeignItem(foreign_item)); + fn visit_foreign_item(&mut self, fi: &'hir ForeignItem<'hir>) { + debug_assert_eq!( + fi.hir_id.owner, + self.definitions.opt_hir_id_to_local_def_id(fi.hir_id).unwrap() + ); + self.with_dep_node_owner(fi.hir_id.owner, fi, |this, hash| { + this.insert_with_hash(fi.span, fi.hir_id, Node::ForeignItem(fi), hash); - self.with_parent(foreign_item.hir_id, |this| { - intravisit::walk_foreign_item(this, foreign_item); + this.with_parent(fi.hir_id, |this| { + intravisit::walk_foreign_item(this, fi); + }); }); } diff --git a/compiler/rustc_middle/src/hir/map/mod.rs b/compiler/rustc_middle/src/hir/map/mod.rs index 37ec3d3d1ca..5e36362ec59 100644 --- a/compiler/rustc_middle/src/hir/map/mod.rs +++ b/compiler/rustc_middle/src/hir/map/mod.rs @@ -205,7 +205,7 @@ impl<'hir> Map<'hir> { ItemKind::TraitAlias(..) => DefKind::TraitAlias, ItemKind::ExternCrate(_) => DefKind::ExternCrate, ItemKind::Use(..) => DefKind::Use, - ItemKind::ForeignMod(..) => DefKind::ForeignMod, + ItemKind::ForeignMod { .. } => DefKind::ForeignMod, ItemKind::GlobalAsm(..) => DefKind::GlobalAsm, ItemKind::Impl { .. } => DefKind::Impl, }, @@ -309,6 +309,13 @@ impl<'hir> Map<'hir> { } } + pub fn foreign_item(&self, id: ForeignItemId) -> &'hir ForeignItem<'hir> { + match self.find(id.hir_id).unwrap() { + Node::ForeignItem(item) => item, + _ => bug!(), + } + } + pub fn body(&self, id: BodyId) -> &'hir Body<'hir> { self.tcx.hir_owner_nodes(id.hir_id.owner).unwrap().bodies.get(&id.hir_id.local_id).unwrap() } @@ -470,6 +477,10 @@ impl<'hir> Map<'hir> { for id in &module.impl_items { visitor.visit_impl_item(self.expect_impl_item(id.hir_id)); } + + for id in &module.foreign_items { + visitor.visit_foreign_item(self.expect_foreign_item(id.hir_id)); + } } /// Retrieves the `Node` corresponding to `id`, panicking if it cannot be found. @@ -718,10 +729,11 @@ impl<'hir> Map<'hir> { let parent = self.get_parent_item(hir_id); if let Some(entry) = self.find_entry(parent) { if let Entry { - node: Node::Item(Item { kind: ItemKind::ForeignMod(ref nm), .. }), .. + node: Node::Item(Item { kind: ItemKind::ForeignMod { abi, .. }, .. }), + .. } = entry { - return nm.abi; + return *abi; } } bug!("expected foreign mod or inlined parent, found {}", self.node_to_string(parent)) @@ -937,6 +949,10 @@ impl<'hir> intravisit::Map<'hir> for Map<'hir> { fn impl_item(&self, id: ImplItemId) -> &'hir ImplItem<'hir> { self.impl_item(id) } + + fn foreign_item(&self, id: ForeignItemId) -> &'hir ForeignItem<'hir> { + self.foreign_item(id) + } } trait Named { @@ -1030,7 +1046,7 @@ fn hir_id_to_string(map: &Map<'_>, id: HirId) -> String { ItemKind::Const(..) => "const", ItemKind::Fn(..) => "fn", ItemKind::Mod(..) => "mod", - ItemKind::ForeignMod(..) => "foreign mod", + ItemKind::ForeignMod { .. } => "foreign mod", ItemKind::GlobalAsm(..) => "global asm", ItemKind::TyAlias(..) => "ty", ItemKind::OpaqueTy(..) => "opaque type", diff --git a/compiler/rustc_middle/src/mir/coverage.rs b/compiler/rustc_middle/src/mir/coverage.rs index 6b46d7c497d..8a6bf9dff7b 100644 --- a/compiler/rustc_middle/src/mir/coverage.rs +++ b/compiler/rustc_middle/src/mir/coverage.rs @@ -21,9 +21,9 @@ rustc_index::newtype_index! { impl ExpressionOperandId { /// An expression operand for a "zero counter", as described in the following references: /// - /// * <https://github.com/rust-lang/llvm-project/blob/llvmorg-8.0.0/llvm/docs/CoverageMappingFormat.rst#counter> - /// * <https://github.com/rust-lang/llvm-project/blob/llvmorg-8.0.0/llvm/docs/CoverageMappingFormat.rst#tag> - /// * <https://github.com/rust-lang/llvm-project/blob/llvmorg-8.0.0/llvm/docs/CoverageMappingFormat.rst#counter-expressions> + /// * <https://github.com/rust-lang/llvm-project/blob/rustc/11.0-2020-10-12/llvm/docs/CoverageMappingFormat.rst#counter> + /// * <https://github.com/rust-lang/llvm-project/blob/rustc/11.0-2020-10-12/llvm/docs/CoverageMappingFormat.rst#tag> + /// * <https://github.com/rust-lang/llvm-project/blob/rustc/11.0-2020-10-12/llvm/docs/CoverageMappingFormat.rst#counter-expressions> /// /// This operand can be used to count two or more separate code regions with a single counter, /// if they run sequentially with no branches, by injecting the `Counter` in a `BasicBlock` for diff --git a/compiler/rustc_middle/src/mir/mod.rs b/compiler/rustc_middle/src/mir/mod.rs index 9289d4708de..814f91b0431 100644 --- a/compiler/rustc_middle/src/mir/mod.rs +++ b/compiler/rustc_middle/src/mir/mod.rs @@ -811,7 +811,7 @@ pub struct LocalDecl<'tcx> { /// after typeck. /// /// This should be sound because the drop flags are fully algebraic, and - /// therefore don't affect the OIBIT or outlives properties of the + /// therefore don't affect the auto-trait or outlives properties of the /// generator. pub internal: bool, diff --git a/compiler/rustc_middle/src/mir/visit.rs b/compiler/rustc_middle/src/mir/visit.rs index ad47c6e75d3..7538818b8af 100644 --- a/compiler/rustc_middle/src/mir/visit.rs +++ b/compiler/rustc_middle/src/mir/visit.rs @@ -254,7 +254,7 @@ macro_rules! make_mir_visitor { macro_rules! basic_blocks { (mut) => (body.basic_blocks_mut().iter_enumerated_mut()); () => (body.basic_blocks().iter_enumerated()); - }; + } for (bb, data) in basic_blocks!($($mutability)?) { self.visit_basic_block_data(bb, data); } @@ -275,7 +275,7 @@ macro_rules! make_mir_visitor { macro_rules! type_annotations { (mut) => (body.user_type_annotations.iter_enumerated_mut()); () => (body.user_type_annotations.iter_enumerated()); - }; + } for (index, annotation) in type_annotations!($($mutability)?) { self.visit_user_type_annotation( @@ -909,7 +909,7 @@ macro_rules! make_mir_visitor { macro_rules! basic_blocks { (mut) => (body.basic_blocks_mut()); () => (body.basic_blocks()); - }; + } let basic_block = & $($mutability)? basic_blocks!($($mutability)?)[location.block]; if basic_block.statements.len() == location.statement_index { if let Some(ref $($mutability)? terminator) = basic_block.terminator { diff --git a/compiler/rustc_middle/src/query/mod.rs b/compiler/rustc_middle/src/query/mod.rs index 634d50368bd..7822ecc2c1f 100644 --- a/compiler/rustc_middle/src/query/mod.rs +++ b/compiler/rustc_middle/src/query/mod.rs @@ -130,8 +130,8 @@ rustc_queries! { storage(ArenaCacheSelector<'tcx>) cache_on_disk_if { key.is_local() } load_cached(tcx, id) { - let generics: Option<ty::Generics> = tcx.queries.on_disk_cache - .try_load_query_result(tcx, id); + let generics: Option<ty::Generics> = tcx.queries.on_disk_cache.as_ref() + .and_then(|c| c.try_load_query_result(tcx, id)); generics } } @@ -635,6 +635,10 @@ rustc_queries! { desc { |tcx| "checking loops in {}", describe_as_module(key, tcx) } } + query check_mod_naked_functions(key: LocalDefId) -> () { + desc { |tcx| "checking naked functions in {}", describe_as_module(key, tcx) } + } + query check_mod_item_types(key: LocalDefId) -> () { desc { |tcx| "checking item types in {}", describe_as_module(key, tcx) } } @@ -688,8 +692,8 @@ rustc_queries! { cache_on_disk_if { true } load_cached(tcx, id) { let typeck_results: Option<ty::TypeckResults<'tcx>> = tcx - .queries.on_disk_cache - .try_load_query_result(tcx, id); + .queries.on_disk_cache.as_ref() + .and_then(|c| c.try_load_query_result(tcx, id)); typeck_results.map(|x| &*tcx.arena.alloc(x)) } diff --git a/compiler/rustc_middle/src/traits/mod.rs b/compiler/rustc_middle/src/traits/mod.rs index 1902a97e21c..0a663f793aa 100644 --- a/compiler/rustc_middle/src/traits/mod.rs +++ b/compiler/rustc_middle/src/traits/mod.rs @@ -71,7 +71,7 @@ pub enum Reveal { /// be observable directly by the user, `Reveal::All` /// should not be used by checks which may expose /// type equality or type contents to the user. - /// There are some exceptions, e.g., around OIBITS and + /// There are some exceptions, e.g., around auto traits and /// transmute-checking, which expose some details, but /// not the whole concrete type of the `impl Trait`. All, diff --git a/compiler/rustc_middle/src/ty/context.rs b/compiler/rustc_middle/src/ty/context.rs index a6f91278a3b..7207e5a179e 100644 --- a/compiler/rustc_middle/src/ty/context.rs +++ b/compiler/rustc_middle/src/ty/context.rs @@ -1096,7 +1096,7 @@ impl<'tcx> TyCtxt<'tcx> { krate: &'tcx hir::Crate<'tcx>, definitions: &'tcx Definitions, dep_graph: DepGraph, - on_disk_query_result_cache: query::OnDiskCache<'tcx>, + on_disk_query_result_cache: Option<query::OnDiskCache<'tcx>>, crate_name: &str, output_filenames: &OutputFilenames, ) -> GlobalCtxt<'tcx> { @@ -1345,7 +1345,7 @@ impl<'tcx> TyCtxt<'tcx> { where E: ty::codec::OpaqueEncoder, { - self.queries.on_disk_cache.serialize(self, encoder) + self.queries.on_disk_cache.as_ref().map(|c| c.serialize(self, encoder)).unwrap_or(Ok(())) } /// If `true`, we should use the MIR-based borrowck, but also diff --git a/compiler/rustc_middle/src/ty/instance.rs b/compiler/rustc_middle/src/ty/instance.rs index f52466d85f8..413c9cca589 100644 --- a/compiler/rustc_middle/src/ty/instance.rs +++ b/compiler/rustc_middle/src/ty/instance.rs @@ -540,7 +540,7 @@ fn polymorphize<'tcx>( struct PolymorphizationFolder<'tcx> { tcx: TyCtxt<'tcx>, - }; + } impl ty::TypeFolder<'tcx> for PolymorphizationFolder<'tcx> { fn tcx<'a>(&'a self) -> TyCtxt<'tcx> { diff --git a/compiler/rustc_middle/src/ty/query/plumbing.rs b/compiler/rustc_middle/src/ty/query/plumbing.rs index d038695283c..d0730bd121c 100644 --- a/compiler/rustc_middle/src/ty/query/plumbing.rs +++ b/compiler/rustc_middle/src/ty/query/plumbing.rs @@ -128,7 +128,7 @@ impl<'tcx> TyCtxt<'tcx> { pub fn try_print_query_stack(handler: &Handler, num_frames: Option<usize>) { eprintln!("query stack during panic:"); - // Be careful reyling on global state here: this code is called from + // Be careful relying on global state here: this code is called from // a panic hook, which means that the global `Handler` may be in a weird // state if it was responsible for triggering the panic. let mut i = 0; @@ -507,10 +507,11 @@ macro_rules! define_queries_struct { (tcx: $tcx:tt, input: ($(([$($modifiers:tt)*] [$($attr:tt)*] [$name:ident]))*)) => { pub struct Queries<$tcx> { - /// This provides access to the incrimental comilation on-disk cache for query results. + /// This provides access to the incremental compilation on-disk cache for query results. /// Do not access this directly. It is only meant to be used by /// `DepGraph::try_mark_green()` and the query infrastructure. - pub(crate) on_disk_cache: OnDiskCache<'tcx>, + /// This is `None` if we are not incremental compilation mode + pub(crate) on_disk_cache: Option<OnDiskCache<'tcx>>, providers: IndexVec<CrateNum, Providers>, fallback_extern_providers: Box<Providers>, @@ -526,7 +527,7 @@ macro_rules! define_queries_struct { pub(crate) fn new( providers: IndexVec<CrateNum, Providers>, fallback_extern_providers: Providers, - on_disk_cache: OnDiskCache<'tcx>, + on_disk_cache: Option<OnDiskCache<'tcx>>, ) -> Self { Queries { providers, diff --git a/compiler/rustc_mir/src/interpret/util.rs b/compiler/rustc_mir/src/interpret/util.rs index e49b1c9f64d..ec90f063a55 100644 --- a/compiler/rustc_mir/src/interpret/util.rs +++ b/compiler/rustc_mir/src/interpret/util.rs @@ -15,7 +15,7 @@ where struct UsedParamsNeedSubstVisitor<'tcx> { tcx: TyCtxt<'tcx>, - }; + } impl<'tcx> TypeVisitor<'tcx> for UsedParamsNeedSubstVisitor<'tcx> { type BreakTy = (); diff --git a/compiler/rustc_mir/src/monomorphize/collector.rs b/compiler/rustc_mir/src/monomorphize/collector.rs index a6f90992172..6370ead97e7 100644 --- a/compiler/rustc_mir/src/monomorphize/collector.rs +++ b/compiler/rustc_mir/src/monomorphize/collector.rs @@ -993,7 +993,7 @@ impl ItemLikeVisitor<'v> for RootCollector<'_, 'v> { match item.kind { hir::ItemKind::ExternCrate(..) | hir::ItemKind::Use(..) - | hir::ItemKind::ForeignMod(..) + | hir::ItemKind::ForeignMod { .. } | hir::ItemKind::TyAlias(..) | hir::ItemKind::Trait(..) | hir::ItemKind::TraitAlias(..) @@ -1066,6 +1066,8 @@ impl ItemLikeVisitor<'v> for RootCollector<'_, 'v> { self.push_if_root(def_id); } } + + fn visit_foreign_item(&mut self, _foreign_item: &'v hir::ForeignItem<'v>) {} } impl RootCollector<'_, 'v> { diff --git a/compiler/rustc_mir/src/transform/coverage/debug.rs b/compiler/rustc_mir/src/transform/coverage/debug.rs index 7f1dc3844b2..e9528557b33 100644 --- a/compiler/rustc_mir/src/transform/coverage/debug.rs +++ b/compiler/rustc_mir/src/transform/coverage/debug.rs @@ -95,18 +95,18 @@ //! //! Depending on the values and combinations, counters can be labeled by: //! -//! * `id` - counter or expression ID (ascending counter IDs, starting at 1, or descending -//! expression IDs, starting at `u32:MAX`) -//! * `block` - the `BasicCoverageBlock` label (for example, `bcb0`) or edge label (for -//! example `bcb0->bcb1`), for counters or expressions assigned to count a -//! `BasicCoverageBlock` or edge. Intermediate expressions (not directly associated with -//! a BCB or edge) will be labeled by their expression ID, unless `operation` is also -//! specified. -//! * `operation` - applied to expressions only, labels include the left-hand-side counter -//! or expression label (lhs operand), the operator (`+` or `-`), and the right-hand-side -//! counter or expression (rhs operand). Expression operand labels are generated -//! recursively, generating labels with nested operations, enclosed in parentheses -//! (for example: `bcb2 + (bcb0 - bcb1)`). +//! * `id` - counter or expression ID (ascending counter IDs, starting at 1, or descending +//! expression IDs, starting at `u32:MAX`) +//! * `block` - the `BasicCoverageBlock` label (for example, `bcb0`) or edge label (for +//! example `bcb0->bcb1`), for counters or expressions assigned to count a +//! `BasicCoverageBlock` or edge. Intermediate expressions (not directly associated with +//! a BCB or edge) will be labeled by their expression ID, unless `operation` is also +//! specified. +//! * `operation` - applied to expressions only, labels include the left-hand-side counter +//! or expression label (lhs operand), the operator (`+` or `-`), and the right-hand-side +//! counter or expression (rhs operand). Expression operand labels are generated +//! recursively, generating labels with nested operations, enclosed in parentheses +//! (for example: `bcb2 + (bcb0 - bcb1)`). use super::graph::{BasicCoverageBlock, BasicCoverageBlockData, CoverageGraph}; use super::spans::CoverageSpan; diff --git a/compiler/rustc_mir_build/src/build/expr/as_rvalue.rs b/compiler/rustc_mir_build/src/build/expr/as_rvalue.rs index b6728c6b2ce..7c34b996055 100644 --- a/compiler/rustc_mir_build/src/build/expr/as_rvalue.rs +++ b/compiler/rustc_mir_build/src/build/expr/as_rvalue.rs @@ -96,7 +96,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { ExprKind::Box { value } => { let value = this.hir.mirror(value); // The `Box<T>` temporary created here is not a part of the HIR, - // and therefore is not considered during generator OIBIT + // and therefore is not considered during generator auto-trait // determination. See the comment about `box` at `yield_in_scope`. let result = this.local_decls.push(LocalDecl::new(expr.ty, expr_span).internal()); this.cfg.push( diff --git a/compiler/rustc_mir_build/src/thir/pattern/check_match.rs b/compiler/rustc_mir_build/src/thir/pattern/check_match.rs index f9fe261bcee..97edbd83b89 100644 --- a/compiler/rustc_mir_build/src/thir/pattern/check_match.rs +++ b/compiler/rustc_mir_build/src/thir/pattern/check_match.rs @@ -1,5 +1,5 @@ -use super::_match::Usefulness::*; -use super::_match::{ +use super::usefulness::Usefulness::*; +use super::usefulness::{ compute_match_usefulness, expand_pattern, MatchArm, MatchCheckCtxt, UsefulnessReport, }; use super::{PatCtxt, PatKind, PatternError}; diff --git a/compiler/rustc_mir_build/src/thir/pattern/_match.rs b/compiler/rustc_mir_build/src/thir/pattern/deconstruct_pat.rs index 79a74e38743..62b4468eeb3 100644 --- a/compiler/rustc_mir_build/src/thir/pattern/_match.rs +++ b/compiler/rustc_mir_build/src/thir/pattern/deconstruct_pat.rs @@ -1,313 +1,16 @@ -//! Note: tests specific to this file can be found in: -//! - ui/pattern/usefulness -//! - ui/or-patterns -//! - ui/consts/const_in_pattern -//! - ui/rfc-2008-non-exhaustive -//! - ui/half-open-range-patterns -//! - probably many others -//! I (Nadrieril) prefer to put new tests in `ui/pattern/usefulness` unless there's a specific -//! reason not to, for example if they depend on a particular feature like or_patterns. -//! -//! This file includes the logic for exhaustiveness and usefulness checking for -//! pattern-matching. Specifically, given a list of patterns for a type, we can -//! tell whether: -//! (a) the patterns cover every possible constructor for the type (exhaustiveness) -//! (b) each pattern is necessary (usefulness) -//! -//! The algorithm implemented here is a modified version of the one described in: -//! <http://moscova.inria.fr/~maranget/papers/warn/index.html> -//! However, to save future implementors from reading the original paper, we -//! summarise the algorithm here to hopefully save time and be a little clearer -//! (without being so rigorous). -//! -//! # Premise -//! -//! The core of the algorithm revolves about a "usefulness" check. In particular, we -//! are trying to compute a predicate `U(P, p)` where `P` is a list of patterns (we refer to this as -//! a matrix). `U(P, p)` represents whether, given an existing list of patterns -//! `P_1 ..= P_m`, adding a new pattern `p` will be "useful" (that is, cover previously- -//! uncovered values of the type). -//! -//! If we have this predicate, then we can easily compute both exhaustiveness of an -//! entire set of patterns and the individual usefulness of each one. -//! (a) the set of patterns is exhaustive iff `U(P, _)` is false (i.e., adding a wildcard -//! match doesn't increase the number of values we're matching) -//! (b) a pattern `P_i` is not useful if `U(P[0..=(i-1), P_i)` is false (i.e., adding a -//! pattern to those that have come before it doesn't increase the number of values -//! we're matching). -//! -//! # Core concept -//! -//! The idea that powers everything that is done in this file is the following: a value is made -//! from a constructor applied to some fields. Examples of constructors are `Some`, `None`, `(,)` -//! (the 2-tuple constructor), `Foo {..}` (the constructor for a struct `Foo`), and `2` (the -//! constructor for the number `2`). Fields are just a (possibly empty) list of values. -//! -//! Some of the constructors listed above might feel weird: `None` and `2` don't take any -//! arguments. This is part of what makes constructors so general: we will consider plain values -//! like numbers and string literals to be constructors that take no arguments, also called "0-ary -//! constructors"; they are the simplest case of constructors. This allows us to see any value as -//! made up from a tree of constructors, each having a given number of children. For example: -//! `(None, Ok(0))` is made from 4 different constructors. -//! -//! This idea can be extended to patterns: a pattern captures a set of possible values, and we can -//! describe this set using constructors. For example, `Err(_)` captures all values of the type -//! `Result<T, E>` that start with the `Err` constructor (for some choice of `T` and `E`). The -//! wildcard `_` captures all values of the given type starting with any of the constructors for -//! that type. -//! -//! We use this to compute whether different patterns might capture a same value. Do the patterns -//! `Ok("foo")` and `Err(_)` capture a common value? The answer is no, because the first pattern -//! captures only values starting with the `Ok` constructor and the second only values starting -//! with the `Err` constructor. Do the patterns `Some(42)` and `Some(1..10)` intersect? They might, -//! since they both capture values starting with `Some`. To be certain, we need to dig under the -//! `Some` constructor and continue asking the question. This is the main idea behind the -//! exhaustiveness algorithm: by looking at patterns constructor-by-constructor, we can efficiently -//! figure out if some new pattern might capture a value that hadn't been captured by previous -//! patterns. -//! -//! Constructors are represented by the `Constructor` enum, and its fields by the `Fields` enum. -//! Most of the complexity of this file resides in transforming between patterns and -//! (`Constructor`, `Fields`) pairs, handling all the special cases correctly. -//! -//! Caveat: this constructors/fields distinction doesn't quite cover every Rust value. For example -//! a value of type `Rc<u64>` doesn't fit this idea very well, nor do various other things. -//! However, this idea covers most of the cases that are relevant to exhaustiveness checking. -//! -//! -//! # Algorithm -//! -//! Recall that `U(P, p)` represents whether, given an existing list of patterns (aka matrix) `P`, -//! adding a new pattern `p` will cover previously-uncovered values of the type. -//! During the course of the algorithm, the rows of the matrix won't just be individual patterns, -//! but rather partially-deconstructed patterns in the form of a list of fields. The paper -//! calls those pattern-vectors, and we will call them pattern-stacks. The same holds for the -//! new pattern `p`. -//! -//! For example, say we have the following: -//! -//! ``` -//! // x: (Option<bool>, Result<()>) -//! match x { -//! (Some(true), _) => {} -//! (None, Err(())) => {} -//! (None, Err(_)) => {} -//! } -//! ``` -//! -//! Here, the matrix `P` starts as: -//! -//! ``` -//! [ -//! [(Some(true), _)], -//! [(None, Err(()))], -//! [(None, Err(_))], -//! ] -//! ``` -//! -//! We can tell it's not exhaustive, because `U(P, _)` is true (we're not covering -//! `[(Some(false), _)]`, for instance). In addition, row 3 is not useful, because -//! all the values it covers are already covered by row 2. -//! -//! A list of patterns can be thought of as a stack, because we are mainly interested in the top of -//! the stack at any given point, and we can pop or apply constructors to get new pattern-stacks. -//! To match the paper, the top of the stack is at the beginning / on the left. -//! -//! There are two important operations on pattern-stacks necessary to understand the algorithm: -//! -//! 1. We can pop a given constructor off the top of a stack. This operation is called -//! `specialize`, and is denoted `S(c, p)` where `c` is a constructor (like `Some` or -//! `None`) and `p` a pattern-stack. -//! If the pattern on top of the stack can cover `c`, this removes the constructor and -//! pushes its arguments onto the stack. It also expands OR-patterns into distinct patterns. -//! Otherwise the pattern-stack is discarded. -//! This essentially filters those pattern-stacks whose top covers the constructor `c` and -//! discards the others. -//! -//! For example, the first pattern above initially gives a stack `[(Some(true), _)]`. If we -//! pop the tuple constructor, we are left with `[Some(true), _]`, and if we then pop the -//! `Some` constructor we get `[true, _]`. If we had popped `None` instead, we would get -//! nothing back. -//! -//! This returns zero or more new pattern-stacks, as follows. We look at the pattern `p_1` -//! on top of the stack, and we have four cases: -//! 1.1. `p_1 = c(r_1, .., r_a)`, i.e. the top of the stack has constructor `c`. We -//! push onto the stack the arguments of this constructor, and return the result: -//! r_1, .., r_a, p_2, .., p_n -//! 1.2. `p_1 = c'(r_1, .., r_a')` where `c ≠c'`. We discard the current stack and -//! return nothing. -//! 1.3. `p_1 = _`. We push onto the stack as many wildcards as the constructor `c` has -//! arguments (its arity), and return the resulting stack: -//! _, .., _, p_2, .., p_n -//! 1.4. `p_1 = r_1 | r_2`. We expand the OR-pattern and then recurse on each resulting -//! stack: -//! S(c, (r_1, p_2, .., p_n)) -//! S(c, (r_2, p_2, .., p_n)) -//! -//! 2. We can pop a wildcard off the top of the stack. This is called `S(_, p)`, where `p` is -//! a pattern-stack. Note: the paper calls this `D(p)`. -//! This is used when we know there are missing constructor cases, but there might be -//! existing wildcard patterns, so to check the usefulness of the matrix, we have to check -//! all its *other* components. -//! -//! It is computed as follows. We look at the pattern `p_1` on top of the stack, -//! and we have three cases: -//! 2.1. `p_1 = c(r_1, .., r_a)`. We discard the current stack and return nothing. -//! 2.2. `p_1 = _`. We return the rest of the stack: -//! p_2, .., p_n -//! 2.3. `p_1 = r_1 | r_2`. We expand the OR-pattern and then recurse on each resulting -//! stack. -//! S(_, (r_1, p_2, .., p_n)) -//! S(_, (r_2, p_2, .., p_n)) -//! -//! Note that the OR-patterns are not always used directly in Rust, but are used to derive the -//! exhaustive integer matching rules, so they're written here for posterity. -//! -//! Both those operations extend straightforwardly to a list or pattern-stacks, i.e. a matrix, by -//! working row-by-row. Popping a constructor ends up keeping only the matrix rows that start with -//! the given constructor, and popping a wildcard keeps those rows that start with a wildcard. -//! -//! -//! The algorithm for computing `U` -//! ------------------------------- -//! The algorithm is inductive (on the number of columns: i.e., components of tuple patterns). -//! That means we're going to check the components from left-to-right, so the algorithm -//! operates principally on the first component of the matrix and new pattern-stack `p`. -//! This algorithm is realised in the `is_useful` function. -//! -//! Base case. (`n = 0`, i.e., an empty tuple pattern) -//! - If `P` already contains an empty pattern (i.e., if the number of patterns `m > 0`), -//! then `U(P, p)` is false. -//! - Otherwise, `P` must be empty, so `U(P, p)` is true. -//! -//! Inductive step. (`n > 0`, i.e., whether there's at least one column -//! [which may then be expanded into further columns later]) -//! We're going to match on the top of the new pattern-stack, `p_1`. -//! - If `p_1 == c(r_1, .., r_a)`, i.e. we have a constructor pattern. -//! Then, the usefulness of `p_1` can be reduced to whether it is useful when -//! we ignore all the patterns in the first column of `P` that involve other constructors. -//! This is where `S(c, P)` comes in: -//! `U(P, p) := U(S(c, P), S(c, p))` -//! -//! For example, if `P` is: -//! -//! ``` -//! [ -//! [Some(true), _], -//! [None, 0], -//! ] -//! ``` -//! -//! and `p` is [Some(false), 0], then we don't care about row 2 since we know `p` only -//! matches values that row 2 doesn't. For row 1 however, we need to dig into the -//! arguments of `Some` to know whether some new value is covered. So we compute -//! `U([[true, _]], [false, 0])`. -//! -//! - If `p_1 == _`, then we look at the list of constructors that appear in the first -//! component of the rows of `P`: -//! + If there are some constructors that aren't present, then we might think that the -//! wildcard `_` is useful, since it covers those constructors that weren't covered -//! before. -//! That's almost correct, but only works if there were no wildcards in those first -//! components. So we need to check that `p` is useful with respect to the rows that -//! start with a wildcard, if there are any. This is where `S(_, x)` comes in: -//! `U(P, p) := U(S(_, P), S(_, p))` -//! -//! For example, if `P` is: -//! -//! ``` -//! [ -//! [_, true, _], -//! [None, false, 1], -//! ] -//! ``` -//! -//! and `p` is [_, false, _], the `Some` constructor doesn't appear in `P`. So if we -//! only had row 2, we'd know that `p` is useful. However row 1 starts with a -//! wildcard, so we need to check whether `U([[true, _]], [false, 1])`. -//! -//! + Otherwise, all possible constructors (for the relevant type) are present. In this -//! case we must check whether the wildcard pattern covers any unmatched value. For -//! that, we can think of the `_` pattern as a big OR-pattern that covers all -//! possible constructors. For `Option`, that would mean `_ = None | Some(_)` for -//! example. The wildcard pattern is useful in this case if it is useful when -//! specialized to one of the possible constructors. So we compute: -//! `U(P, p) := ∃(k ϵ constructors) U(S(k, P), S(k, p))` -//! -//! For example, if `P` is: -//! -//! ``` -//! [ -//! [Some(true), _], -//! [None, false], -//! ] -//! ``` -//! -//! and `p` is [_, false], both `None` and `Some` constructors appear in the first -//! components of `P`. We will therefore try popping both constructors in turn: we -//! compute `U([[true, _]], [_, false])` for the `Some` constructor, and `U([[false]], -//! [false])` for the `None` constructor. The first case returns true, so we know that -//! `p` is useful for `P`. Indeed, it matches `[Some(false), _]` that wasn't matched -//! before. -//! -//! - If `p_1 == r_1 | r_2`, then the usefulness depends on each `r_i` separately: -//! `U(P, p) := U(P, (r_1, p_2, .., p_n)) -//! || U(P, (r_2, p_2, .., p_n))` -//! -//! Modifications to the algorithm -//! ------------------------------ -//! The algorithm in the paper doesn't cover some of the special cases that arise in Rust, for -//! example uninhabited types and variable-length slice patterns. These are drawn attention to -//! throughout the code below. I'll make a quick note here about how exhaustive integer matching is -//! accounted for, though. -//! -//! Exhaustive integer matching -//! --------------------------- -//! An integer type can be thought of as a (huge) sum type: 1 | 2 | 3 | ... -//! So to support exhaustive integer matching, we can make use of the logic in the paper for -//! OR-patterns. However, we obviously can't just treat ranges x..=y as individual sums, because -//! they are likely gigantic. So we instead treat ranges as constructors of the integers. This means -//! that we have a constructor *of* constructors (the integers themselves). We then need to work -//! through all the inductive step rules above, deriving how the ranges would be treated as -//! OR-patterns, and making sure that they're treated in the same way even when they're ranges. -//! There are really only four special cases here: -//! - When we match on a constructor that's actually a range, we have to treat it as if we would -//! an OR-pattern. -//! + It turns out that we can simply extend the case for single-value patterns in -//! `specialize` to either be *equal* to a value constructor, or *contained within* a range -//! constructor. -//! + When the pattern itself is a range, you just want to tell whether any of the values in -//! the pattern range coincide with values in the constructor range, which is precisely -//! intersection. -//! Since when encountering a range pattern for a value constructor, we also use inclusion, it -//! means that whenever the constructor is a value/range and the pattern is also a value/range, -//! we can simply use intersection to test usefulness. -//! - When we're testing for usefulness of a pattern and the pattern's first component is a -//! wildcard. -//! + If all the constructors appear in the matrix, we have a slight complication. By default, -//! the behaviour (i.e., a disjunction over specialised matrices for each constructor) is -//! invalid, because we want a disjunction over every *integer* in each range, not just a -//! disjunction over every range. This is a bit more tricky to deal with: essentially we need -//! to form equivalence classes of subranges of the constructor range for which the behaviour -//! of the matrix `P` and new pattern `p` are the same. This is described in more -//! detail in `Constructor::split`. -//! + If some constructors are missing from the matrix, it turns out we don't need to do -//! anything special (because we know none of the integers are actually wildcards: i.e., we -//! can't span wildcards using ranges). +//! This module provides functions to deconstruct and reconstruct patterns into a constructor +//! applied to some fields. This is used by the `_match` module to compute pattern +//! usefulness/exhaustiveness. use self::Constructor::*; use self::SliceKind::*; -use self::Usefulness::*; -use self::WitnessPreference::*; + +use super::compare_const_vals; +use super::usefulness::{MatchCheckCtxt, PatCtxt}; +use super::{FieldPat, Pat, PatKind, PatRange}; use rustc_data_structures::captures::Captures; -use rustc_data_structures::fx::FxHashSet; -use rustc_data_structures::sync::OnceCell; use rustc_index::vec::Idx; -use super::{compare_const_vals, PatternFoldable, PatternFolder}; -use super::{FieldPat, Pat, PatKind, PatRange}; - -use rustc_arena::TypedArena; use rustc_attr::{SignedInt, UnsignedInt}; use rustc_hir::def_id::DefId; use rustc_hir::{HirId, RangeEnd}; @@ -321,281 +24,344 @@ use rustc_target::abi::{Integer, Size, VariantIdx}; use smallvec::{smallvec, SmallVec}; use std::cmp::{self, max, min, Ordering}; -use std::fmt; -use std::iter::{FromIterator, IntoIterator}; +use std::iter::IntoIterator; use std::ops::RangeInclusive; -crate fn expand_pattern<'tcx>(pat: Pat<'tcx>) -> Pat<'tcx> { - LiteralExpander.fold_pattern(&pat) -} - -struct LiteralExpander; - -impl<'tcx> PatternFolder<'tcx> for LiteralExpander { - fn fold_pattern(&mut self, pat: &Pat<'tcx>) -> Pat<'tcx> { - debug!("fold_pattern {:?} {:?} {:?}", pat, pat.ty.kind(), pat.kind); - match (pat.ty.kind(), pat.kind.as_ref()) { - (_, PatKind::Binding { subpattern: Some(s), .. }) => s.fold_with(self), - (_, PatKind::AscribeUserType { subpattern: s, .. }) => s.fold_with(self), - (ty::Ref(_, t, _), PatKind::Constant { .. }) if t.is_str() => { - // Treat string literal patterns as deref patterns to a `str` constant, i.e. - // `&CONST`. This expands them like other const patterns. This could have been done - // in `const_to_pat`, but that causes issues with the rest of the matching code. - let mut new_pat = pat.super_fold_with(self); - // Make a fake const pattern of type `str` (instead of `&str`). That the carried - // constant value still knows it is of type `&str`. - new_pat.ty = t; - Pat { - kind: Box::new(PatKind::Deref { subpattern: new_pat }), - span: pat.span, - ty: pat.ty, - } - } - _ => pat.super_fold_with(self), - } - } -} - -impl<'tcx> Pat<'tcx> { - pub(super) fn is_wildcard(&self) -> bool { - matches!(*self.kind, PatKind::Binding { subpattern: None, .. } | PatKind::Wild) - } -} - -/// A row of a matrix. Rows of len 1 are very common, which is why `SmallVec[_; 2]` -/// works well. -#[derive(Debug, Clone)] -struct PatStack<'p, 'tcx> { - pats: SmallVec<[&'p Pat<'tcx>; 2]>, - /// Cache for the constructor of the head - head_ctor: OnceCell<Constructor<'tcx>>, +/// An inclusive interval, used for precise integer exhaustiveness checking. +/// `IntRange`s always store a contiguous range. This means that values are +/// encoded such that `0` encodes the minimum value for the integer, +/// regardless of the signedness. +/// For example, the pattern `-128..=127i8` is encoded as `0..=255`. +/// This makes comparisons and arithmetic on interval endpoints much more +/// straightforward. See `signed_bias` for details. +/// +/// `IntRange` is never used to encode an empty range or a "range" that wraps +/// around the (offset) space: i.e., `range.lo <= range.hi`. +#[derive(Clone, Debug)] +pub(super) struct IntRange<'tcx> { + range: RangeInclusive<u128>, + ty: Ty<'tcx>, + span: Span, } -impl<'p, 'tcx> PatStack<'p, 'tcx> { - fn from_pattern(pat: &'p Pat<'tcx>) -> Self { - Self::from_vec(smallvec![pat]) - } - - fn from_vec(vec: SmallVec<[&'p Pat<'tcx>; 2]>) -> Self { - PatStack { pats: vec, head_ctor: OnceCell::new() } +impl<'tcx> IntRange<'tcx> { + #[inline] + fn is_integral(ty: Ty<'_>) -> bool { + matches!(ty.kind(), ty::Char | ty::Int(_) | ty::Uint(_) | ty::Bool) } - fn is_empty(&self) -> bool { - self.pats.is_empty() + fn is_singleton(&self) -> bool { + self.range.start() == self.range.end() } - fn len(&self) -> usize { - self.pats.len() + fn boundaries(&self) -> (u128, u128) { + (*self.range.start(), *self.range.end()) } - fn head(&self) -> &'p Pat<'tcx> { - self.pats[0] + /// Don't treat `usize`/`isize` exhaustively unless the `precise_pointer_size_matching` feature + /// is enabled. + fn treat_exhaustively(&self, tcx: TyCtxt<'tcx>) -> bool { + !self.ty.is_ptr_sized_integral() || tcx.features().precise_pointer_size_matching } - fn head_ctor<'a>(&'a self, cx: &MatchCheckCtxt<'p, 'tcx>) -> &'a Constructor<'tcx> { - self.head_ctor.get_or_init(|| pat_constructor(cx, self.head())) + #[inline] + fn integral_size_and_signed_bias(tcx: TyCtxt<'tcx>, ty: Ty<'_>) -> Option<(Size, u128)> { + match *ty.kind() { + ty::Bool => Some((Size::from_bytes(1), 0)), + ty::Char => Some((Size::from_bytes(4), 0)), + ty::Int(ity) => { + let size = Integer::from_attr(&tcx, SignedInt(ity)).size(); + Some((size, 1u128 << (size.bits() as u128 - 1))) + } + ty::Uint(uty) => Some((Integer::from_attr(&tcx, UnsignedInt(uty)).size(), 0)), + _ => None, + } } - fn iter(&self) -> impl Iterator<Item = &Pat<'tcx>> { - self.pats.iter().copied() + #[inline] + fn from_const( + tcx: TyCtxt<'tcx>, + param_env: ty::ParamEnv<'tcx>, + value: &Const<'tcx>, + span: Span, + ) -> Option<IntRange<'tcx>> { + if let Some((target_size, bias)) = Self::integral_size_and_signed_bias(tcx, value.ty) { + let ty = value.ty; + let val = (|| { + if let ty::ConstKind::Value(ConstValue::Scalar(scalar)) = value.val { + // For this specific pattern we can skip a lot of effort and go + // straight to the result, after doing a bit of checking. (We + // could remove this branch and just fall through, which + // is more general but much slower.) + if let Ok(bits) = scalar.to_bits_or_ptr(target_size, &tcx) { + return Some(bits); + } + } + // This is a more general form of the previous case. + value.try_eval_bits(tcx, param_env, ty) + })()?; + let val = val ^ bias; + Some(IntRange { range: val..=val, ty, span }) + } else { + None + } } - // If the first pattern is an or-pattern, expand this pattern. Otherwise, return `None`. - fn expand_or_pat(&self) -> Option<Vec<Self>> { - if self.is_empty() { - None - } else if let PatKind::Or { pats } = &*self.head().kind { - Some( - pats.iter() - .map(|pat| { - let mut new_patstack = PatStack::from_pattern(pat); - new_patstack.pats.extend_from_slice(&self.pats[1..]); - new_patstack - }) - .collect(), - ) + #[inline] + fn from_range( + tcx: TyCtxt<'tcx>, + lo: u128, + hi: u128, + ty: Ty<'tcx>, + end: &RangeEnd, + span: Span, + ) -> Option<IntRange<'tcx>> { + if Self::is_integral(ty) { + // Perform a shift if the underlying types are signed, + // which makes the interval arithmetic simpler. + let bias = IntRange::signed_bias(tcx, ty); + let (lo, hi) = (lo ^ bias, hi ^ bias); + let offset = (*end == RangeEnd::Excluded) as u128; + if lo > hi || (lo == hi && *end == RangeEnd::Excluded) { + // This should have been caught earlier by E0030. + bug!("malformed range pattern: {}..={}", lo, (hi - offset)); + } + Some(IntRange { range: lo..=(hi - offset), ty, span }) } else { None } } - /// This computes `S(self.head_ctor(), self)`. See top of the file for explanations. - /// - /// Structure patterns with a partial wild pattern (Foo { a: 42, .. }) have their missing - /// fields filled with wild patterns. - /// - /// This is roughly the inverse of `Constructor::apply`. - fn pop_head_constructor(&self, ctor_wild_subpatterns: &Fields<'p, 'tcx>) -> PatStack<'p, 'tcx> { - // We pop the head pattern and push the new fields extracted from the arguments of - // `self.head()`. - let new_fields = ctor_wild_subpatterns.replace_with_pattern_arguments(self.head()); - new_fields.push_on_patstack(&self.pats[1..]) + // The return value of `signed_bias` should be XORed with an endpoint to encode/decode it. + fn signed_bias(tcx: TyCtxt<'tcx>, ty: Ty<'tcx>) -> u128 { + match *ty.kind() { + ty::Int(ity) => { + let bits = Integer::from_attr(&tcx, SignedInt(ity)).size().bits() as u128; + 1u128 << (bits - 1) + } + _ => 0, + } } -} -impl<'p, 'tcx> Default for PatStack<'p, 'tcx> { - fn default() -> Self { - Self::from_vec(smallvec![]) + fn is_subrange(&self, other: &Self) -> bool { + other.range.start() <= self.range.start() && self.range.end() <= other.range.end() } -} -impl<'p, 'tcx> PartialEq for PatStack<'p, 'tcx> { - fn eq(&self, other: &Self) -> bool { - self.pats == other.pats + fn intersection(&self, tcx: TyCtxt<'tcx>, other: &Self) -> Option<Self> { + let ty = self.ty; + let (lo, hi) = self.boundaries(); + let (other_lo, other_hi) = other.boundaries(); + if self.treat_exhaustively(tcx) { + if lo <= other_hi && other_lo <= hi { + let span = other.span; + Some(IntRange { range: max(lo, other_lo)..=min(hi, other_hi), ty, span }) + } else { + None + } + } else { + // If the range should not be treated exhaustively, fallback to checking for inclusion. + if self.is_subrange(other) { Some(self.clone()) } else { None } + } } -} -impl<'p, 'tcx> FromIterator<&'p Pat<'tcx>> for PatStack<'p, 'tcx> { - fn from_iter<T>(iter: T) -> Self - where - T: IntoIterator<Item = &'p Pat<'tcx>>, - { - Self::from_vec(iter.into_iter().collect()) + fn suspicious_intersection(&self, other: &Self) -> bool { + // `false` in the following cases: + // 1 ---- // 1 ---------- // 1 ---- // 1 ---- + // 2 ---------- // 2 ---- // 2 ---- // 2 ---- + // + // The following are currently `false`, but could be `true` in the future (#64007): + // 1 --------- // 1 --------- + // 2 ---------- // 2 ---------- + // + // `true` in the following cases: + // 1 ------- // 1 ------- + // 2 -------- // 2 ------- + let (lo, hi) = self.boundaries(); + let (other_lo, other_hi) = other.boundaries(); + lo == other_hi || hi == other_lo } -} -/// A 2D matrix. -#[derive(Clone, PartialEq)] -struct Matrix<'p, 'tcx> { - patterns: Vec<PatStack<'p, 'tcx>>, -} + fn to_pat(&self, tcx: TyCtxt<'tcx>) -> Pat<'tcx> { + let (lo, hi) = self.boundaries(); -impl<'p, 'tcx> Matrix<'p, 'tcx> { - fn empty() -> Self { - Matrix { patterns: vec![] } - } + let bias = IntRange::signed_bias(tcx, self.ty); + let (lo, hi) = (lo ^ bias, hi ^ bias); - /// Pushes a new row to the matrix. If the row starts with an or-pattern, this expands it. - fn push(&mut self, row: PatStack<'p, 'tcx>) { - if let Some(rows) = row.expand_or_pat() { - for row in rows { - // We recursively expand the or-patterns of the new rows. - // This is necessary as we might have `0 | (1 | 2)` or e.g., `x @ 0 | x @ (1 | 2)`. - self.push(row) - } - } else { - self.patterns.push(row); - } - } + let ty = ty::ParamEnv::empty().and(self.ty); + let lo_const = ty::Const::from_bits(tcx, lo, ty); + let hi_const = ty::Const::from_bits(tcx, hi, ty); - /// Iterate over the first component of each row - fn heads<'a>(&'a self) -> impl Iterator<Item = &'a Pat<'tcx>> + Captures<'p> { - self.patterns.iter().map(|r| r.head()) - } + let kind = if lo == hi { + PatKind::Constant { value: lo_const } + } else { + PatKind::Range(PatRange { lo: lo_const, hi: hi_const, end: RangeEnd::Included }) + }; - /// Iterate over the first constructor of each row - fn head_ctors<'a>( - &'a self, - cx: &'a MatchCheckCtxt<'p, 'tcx>, - ) -> impl Iterator<Item = &'a Constructor<'tcx>> + Captures<'a> + Captures<'p> { - self.patterns.iter().map(move |r| r.head_ctor(cx)) + // This is a brand new pattern, so we don't reuse `self.span`. + Pat { ty: self.ty, span: DUMMY_SP, kind: Box::new(kind) } } - /// This computes `S(constructor, self)`. See top of the file for explanations. - fn specialize_constructor( + /// For exhaustive integer matching, some constructors are grouped within other constructors + /// (namely integer typed values are grouped within ranges). However, when specialising these + /// constructors, we want to be specialising for the underlying constructors (the integers), not + /// the groups (the ranges). Thus we need to split the groups up. Splitting them up naïvely would + /// mean creating a separate constructor for every single value in the range, which is clearly + /// impractical. However, observe that for some ranges of integers, the specialisation will be + /// identical across all values in that range (i.e., there are equivalence classes of ranges of + /// constructors based on their `U(S(c, P), S(c, p))` outcome). These classes are grouped by + /// the patterns that apply to them (in the matrix `P`). We can split the range whenever the + /// patterns that apply to that range (specifically: the patterns that *intersect* with that range) + /// change. + /// Our solution, therefore, is to split the range constructor into subranges at every single point + /// the group of intersecting patterns changes (using the method described below). + /// And voilà ! We're testing precisely those ranges that we need to, without any exhaustive matching + /// on actual integers. The nice thing about this is that the number of subranges is linear in the + /// number of rows in the matrix (i.e., the number of cases in the `match` statement), so we don't + /// need to be worried about matching over gargantuan ranges. + /// + /// Essentially, given the first column of a matrix representing ranges, looking like the following: + /// + /// |------| |----------| |-------| || + /// |-------| |-------| |----| || + /// |---------| + /// + /// We split the ranges up into equivalence classes so the ranges are no longer overlapping: + /// + /// |--|--|||-||||--||---|||-------| |-|||| || + /// + /// The logic for determining how to split the ranges is fairly straightforward: we calculate + /// boundaries for each interval range, sort them, then create constructors for each new interval + /// between every pair of boundary points. (This essentially sums up to performing the intuitive + /// merging operation depicted above.) + fn split<'p>( &self, pcx: PatCtxt<'_, 'p, 'tcx>, - ctor: &Constructor<'tcx>, - ctor_wild_subpatterns: &Fields<'p, 'tcx>, - ) -> Matrix<'p, 'tcx> { - self.patterns - .iter() - .filter(|r| ctor.is_covered_by(pcx, r.head_ctor(pcx.cx))) - .map(|r| r.pop_head_constructor(ctor_wild_subpatterns)) - .collect() - } -} + hir_id: Option<HirId>, + ) -> SmallVec<[Constructor<'tcx>; 1]> { + let ty = pcx.ty; -/// Pretty-printer for matrices of patterns, example: -/// -/// ```text -/// +++++++++++++++++++++++++++++ -/// + _ + [] + -/// +++++++++++++++++++++++++++++ -/// + true + [First] + -/// +++++++++++++++++++++++++++++ -/// + true + [Second(true)] + -/// +++++++++++++++++++++++++++++ -/// + false + [_] + -/// +++++++++++++++++++++++++++++ -/// + _ + [_, _, tail @ ..] + -/// +++++++++++++++++++++++++++++ -/// ``` -impl<'p, 'tcx> fmt::Debug for Matrix<'p, 'tcx> { - fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { - write!(f, "\n")?; - - let Matrix { patterns: m, .. } = self; - let pretty_printed_matrix: Vec<Vec<String>> = - m.iter().map(|row| row.iter().map(|pat| format!("{:?}", pat)).collect()).collect(); - - let column_count = m.iter().map(|row| row.len()).max().unwrap_or(0); - assert!(m.iter().all(|row| row.len() == column_count)); - let column_widths: Vec<usize> = (0..column_count) - .map(|col| pretty_printed_matrix.iter().map(|row| row[col].len()).max().unwrap_or(0)) - .collect(); - - let total_width = column_widths.iter().cloned().sum::<usize>() + column_count * 3 + 1; - let br = "+".repeat(total_width); - write!(f, "{}\n", br)?; - for row in pretty_printed_matrix { - write!(f, "+")?; - for (column, pat_str) in row.into_iter().enumerate() { - write!(f, " ")?; - write!(f, "{:1$}", pat_str, column_widths[column])?; - write!(f, " +")?; - } - write!(f, "\n")?; - write!(f, "{}\n", br)?; + /// Represents a border between 2 integers. Because the intervals spanning borders + /// must be able to cover every integer, we need to be able to represent + /// 2^128 + 1 such borders. + #[derive(Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Debug)] + enum Border { + JustBefore(u128), + AfterMax, } - Ok(()) - } -} -impl<'p, 'tcx> FromIterator<PatStack<'p, 'tcx>> for Matrix<'p, 'tcx> { - fn from_iter<T>(iter: T) -> Self - where - T: IntoIterator<Item = PatStack<'p, 'tcx>>, - { - let mut matrix = Matrix::empty(); - for x in iter { - // Using `push` ensures we correctly expand or-patterns. - matrix.push(x); + // A function for extracting the borders of an integer interval. + fn range_borders(r: IntRange<'_>) -> impl Iterator<Item = Border> { + let (lo, hi) = r.range.into_inner(); + let from = Border::JustBefore(lo); + let to = match hi.checked_add(1) { + Some(m) => Border::JustBefore(m), + None => Border::AfterMax, + }; + vec![from, to].into_iter() } - matrix + + // Collect the span and range of all the intersecting ranges to lint on likely + // incorrect range patterns. (#63987) + let mut overlaps = vec![]; + let row_len = pcx.matrix.column_count().unwrap_or(0); + // `borders` is the set of borders between equivalence classes: each equivalence + // class lies between 2 borders. + let row_borders = pcx + .matrix + .head_ctors(pcx.cx) + .filter_map(|ctor| ctor.as_int_range()) + .filter_map(|range| { + let intersection = self.intersection(pcx.cx.tcx, &range); + let should_lint = self.suspicious_intersection(&range); + if let (Some(range), 1, true) = (&intersection, row_len, should_lint) { + // FIXME: for now, only check for overlapping ranges on simple range + // patterns. Otherwise with the current logic the following is detected + // as overlapping: + // match (10u8, true) { + // (0 ..= 125, false) => {} + // (126 ..= 255, false) => {} + // (0 ..= 255, true) => {} + // } + overlaps.push(range.clone()); + } + intersection + }) + .flat_map(range_borders); + let self_borders = range_borders(self.clone()); + let mut borders: Vec<_> = row_borders.chain(self_borders).collect(); + borders.sort_unstable(); + + self.lint_overlapping_patterns(pcx.cx.tcx, hir_id, ty, overlaps); + + // We're going to iterate through every adjacent pair of borders, making sure that + // each represents an interval of nonnegative length, and convert each such + // interval into a constructor. + borders + .array_windows() + .filter_map(|&pair| match pair { + [Border::JustBefore(n), Border::JustBefore(m)] => { + if n < m { + Some(n..=(m - 1)) + } else { + None + } + } + [Border::JustBefore(n), Border::AfterMax] => Some(n..=u128::MAX), + [Border::AfterMax, _] => None, + }) + .map(|range| IntRange { range, ty, span: pcx.span }) + .map(IntRange) + .collect() } -} -crate struct MatchCheckCtxt<'a, 'tcx> { - crate tcx: TyCtxt<'tcx>, - /// The module in which the match occurs. This is necessary for - /// checking inhabited-ness of types because whether a type is (visibly) - /// inhabited can depend on whether it was defined in the current module or - /// not. E.g., `struct Foo { _private: ! }` cannot be seen to be empty - /// outside it's module and should not be matchable with an empty match - /// statement. - crate module: DefId, - crate param_env: ty::ParamEnv<'tcx>, - crate pattern_arena: &'a TypedArena<Pat<'tcx>>, -} + fn lint_overlapping_patterns( + &self, + tcx: TyCtxt<'tcx>, + hir_id: Option<HirId>, + ty: Ty<'tcx>, + overlaps: Vec<IntRange<'tcx>>, + ) { + if let (true, Some(hir_id)) = (!overlaps.is_empty(), hir_id) { + tcx.struct_span_lint_hir( + lint::builtin::OVERLAPPING_PATTERNS, + hir_id, + self.span, + |lint| { + let mut err = lint.build("multiple patterns covering the same range"); + err.span_label(self.span, "overlapping patterns"); + for int_range in overlaps { + // Use the real type for user display of the ranges: + err.span_label( + int_range.span, + &format!( + "this range overlaps on `{}`", + IntRange { range: int_range.range, ty, span: DUMMY_SP }.to_pat(tcx), + ), + ); + } + err.emit(); + }, + ); + } + } -impl<'a, 'tcx> MatchCheckCtxt<'a, 'tcx> { - fn is_uninhabited(&self, ty: Ty<'tcx>) -> bool { - if self.tcx.features().exhaustive_patterns { - self.tcx.is_ty_uninhabited_from(self.module, ty, self.param_env) + /// See `Constructor::is_covered_by` + fn is_covered_by<'p>(&self, pcx: PatCtxt<'_, 'p, 'tcx>, other: &Self) -> bool { + if self.intersection(pcx.cx.tcx, other).is_some() { + // Constructor splitting should ensure that all intersections we encounter are actually + // inclusions. + assert!(self.is_subrange(other)); + true } else { false } } +} - /// Returns whether the given type is an enum from another crate declared `#[non_exhaustive]`. - fn is_foreign_non_exhaustive_enum(&self, ty: Ty<'tcx>) -> bool { - match ty.kind() { - ty::Adt(def, ..) => { - def.is_enum() && def.is_variant_list_non_exhaustive() && !def.did.is_local() - } - _ => false, - } +/// Ignore spans when comparing, they don't carry semantic information as they are only for lints. +impl<'tcx> std::cmp::PartialEq for IntRange<'tcx> { + fn eq(&self, other: &Self) -> bool { + self.range == other.range && self.ty == other.ty } } @@ -630,7 +396,7 @@ impl SliceKind { /// A constructor for array and slice patterns. #[derive(Copy, Clone, Debug, PartialEq, Eq)] -struct Slice { +pub(super) struct Slice { /// `None` if the matched value is a slice, `Some(n)` if it is an array of size `n`. array_len: Option<u64>, /// The kind of pattern it is: fixed-length `[x, y]` or variable length `[x, .., y]`. @@ -785,7 +551,7 @@ impl Slice { /// constructor. `Constructor::apply` reconstructs the pattern from a pair of `Constructor` and /// `Fields`. #[derive(Clone, Debug, PartialEq)] -enum Constructor<'tcx> { +pub(super) enum Constructor<'tcx> { /// The constructor for patterns that have a single constructor, like tuples, struct patterns /// and fixed-length arrays. Single, @@ -811,7 +577,7 @@ enum Constructor<'tcx> { } impl<'tcx> Constructor<'tcx> { - fn is_wildcard(&self) -> bool { + pub(super) fn is_wildcard(&self) -> bool { matches!(self, Wildcard) } @@ -840,6 +606,67 @@ impl<'tcx> Constructor<'tcx> { } } + /// Determines the constructor that the given pattern can be specialized to. + pub(super) fn from_pat<'p>(cx: &MatchCheckCtxt<'p, 'tcx>, pat: &'p Pat<'tcx>) -> Self { + match pat.kind.as_ref() { + PatKind::AscribeUserType { .. } => bug!(), // Handled by `expand_pattern` + PatKind::Binding { .. } | PatKind::Wild => Wildcard, + PatKind::Leaf { .. } | PatKind::Deref { .. } => Single, + &PatKind::Variant { adt_def, variant_index, .. } => { + Variant(adt_def.variants[variant_index].def_id) + } + PatKind::Constant { value } => { + if let Some(int_range) = IntRange::from_const(cx.tcx, cx.param_env, value, pat.span) + { + IntRange(int_range) + } else { + match pat.ty.kind() { + ty::Float(_) => FloatRange(value, value, RangeEnd::Included), + // In `expand_pattern`, we convert string literals to `&CONST` patterns with + // `CONST` a pattern of type `str`. In truth this contains a constant of type + // `&str`. + ty::Str => Str(value), + // All constants that can be structurally matched have already been expanded + // into the corresponding `Pat`s by `const_to_pat`. Constants that remain are + // opaque. + _ => Opaque, + } + } + } + &PatKind::Range(PatRange { lo, hi, end }) => { + let ty = lo.ty; + if let Some(int_range) = IntRange::from_range( + cx.tcx, + lo.eval_bits(cx.tcx, cx.param_env, lo.ty), + hi.eval_bits(cx.tcx, cx.param_env, hi.ty), + ty, + &end, + pat.span, + ) { + IntRange(int_range) + } else { + FloatRange(lo, hi, end) + } + } + PatKind::Array { prefix, slice, suffix } | PatKind::Slice { prefix, slice, suffix } => { + let array_len = match pat.ty.kind() { + ty::Array(_, length) => Some(length.eval_usize(cx.tcx, cx.param_env)), + ty::Slice(_) => None, + _ => span_bug!(pat.span, "bad ty {:?} for slice pattern", pat.ty), + }; + let prefix = prefix.len() as u64; + let suffix = suffix.len() as u64; + let kind = if slice.is_some() { + VarLen(prefix, suffix) + } else { + FixedLen(prefix + suffix) + }; + Slice(Slice::new(array_len, kind)) + } + PatKind::Or { .. } => bug!("Or-pattern should have been expanded earlier on."), + } + } + /// Some constructors (namely `Wildcard`, `IntRange` and `Slice`) actually stand for a set of actual /// constructors (like variants, integers or fixed-sized slices). When specializing for these /// constructors, we want to be specialising for the actual underlying constructors. @@ -856,7 +683,11 @@ impl<'tcx> Constructor<'tcx> { /// /// `hir_id` is `None` when we're evaluating the wildcard pattern. In that case we do not want /// to lint for overlapping ranges. - fn split<'p>(&self, pcx: PatCtxt<'_, 'p, 'tcx>, hir_id: Option<HirId>) -> SmallVec<[Self; 1]> { + pub(super) fn split<'p>( + &self, + pcx: PatCtxt<'_, 'p, 'tcx>, + hir_id: Option<HirId>, + ) -> SmallVec<[Self; 1]> { debug!("Constructor::split({:#?}, {:#?})", self, pcx.matrix); match self { @@ -898,7 +729,7 @@ impl<'tcx> Constructor<'tcx> { /// Returns whether `self` is covered by `other`, i.e. whether `self` is a subset of `other`. /// For the simple cases, this is simply checking for equality. For the "grouped" constructors, /// this checks for inclusion. - fn is_covered_by<'p>(&self, pcx: PatCtxt<'_, 'p, 'tcx>, other: &Self) -> bool { + pub(super) fn is_covered_by<'p>(&self, pcx: PatCtxt<'_, 'p, 'tcx>, other: &Self) -> bool { // This must be kept in sync with `is_covered_by_any`. match (self, other) { // Wildcards cover anything @@ -984,92 +815,204 @@ impl<'tcx> Constructor<'tcx> { } } } +} - /// Apply a constructor to a list of patterns, yielding a new pattern. `pats` - /// must have as many elements as this constructor's arity. - /// - /// This is roughly the inverse of `specialize_constructor`. - /// - /// Examples: - /// `self`: `Constructor::Single` - /// `ty`: `(u32, u32, u32)` - /// `pats`: `[10, 20, _]` - /// returns `(10, 20, _)` - /// - /// `self`: `Constructor::Variant(Option::Some)` - /// `ty`: `Option<bool>` - /// `pats`: `[false]` - /// returns `Some(false)` - fn apply<'p>(&self, pcx: PatCtxt<'_, 'p, 'tcx>, fields: Fields<'p, 'tcx>) -> Pat<'tcx> { - let mut subpatterns = fields.all_patterns(); +/// This determines the set of all possible constructors of a pattern matching +/// values of type `left_ty`. For vectors, this would normally be an infinite set +/// but is instead bounded by the maximum fixed length of slice patterns in +/// the column of patterns being analyzed. +/// +/// We make sure to omit constructors that are statically impossible. E.g., for +/// `Option<!>`, we do not include `Some(_)` in the returned list of constructors. +/// Invariant: this returns an empty `Vec` if and only if the type is uninhabited (as determined by +/// `cx.is_uninhabited()`). +fn all_constructors<'p, 'tcx>(pcx: PatCtxt<'_, 'p, 'tcx>) -> Vec<Constructor<'tcx>> { + debug!("all_constructors({:?})", pcx.ty); + let cx = pcx.cx; + let make_range = |start, end| { + IntRange( + // `unwrap()` is ok because we know the type is an integer. + IntRange::from_range(cx.tcx, start, end, pcx.ty, &RangeEnd::Included, pcx.span) + .unwrap(), + ) + }; + match pcx.ty.kind() { + ty::Bool => vec![make_range(0, 1)], + ty::Array(sub_ty, len) if len.try_eval_usize(cx.tcx, cx.param_env).is_some() => { + let len = len.eval_usize(cx.tcx, cx.param_env); + if len != 0 && cx.is_uninhabited(sub_ty) { + vec![] + } else { + vec![Slice(Slice::new(Some(len), VarLen(0, 0)))] + } + } + // Treat arrays of a constant but unknown length like slices. + ty::Array(sub_ty, _) | ty::Slice(sub_ty) => { + let kind = if cx.is_uninhabited(sub_ty) { FixedLen(0) } else { VarLen(0, 0) }; + vec![Slice(Slice::new(None, kind))] + } + ty::Adt(def, substs) if def.is_enum() => { + // If the enum is declared as `#[non_exhaustive]`, we treat it as if it had an + // additional "unknown" constructor. + // There is no point in enumerating all possible variants, because the user can't + // actually match against them all themselves. So we always return only the fictitious + // constructor. + // E.g., in an example like: + // + // ``` + // let err: io::ErrorKind = ...; + // match err { + // io::ErrorKind::NotFound => {}, + // } + // ``` + // + // we don't want to show every possible IO error, but instead have only `_` as the + // witness. + let is_declared_nonexhaustive = cx.is_foreign_non_exhaustive_enum(pcx.ty); - let pat = match self { - Single | Variant(_) => match pcx.ty.kind() { - ty::Adt(..) | ty::Tuple(..) => { - let subpatterns = subpatterns - .enumerate() - .map(|(i, p)| FieldPat { field: Field::new(i), pattern: p }) - .collect(); + // If `exhaustive_patterns` is disabled and our scrutinee is an empty enum, we treat it + // as though it had an "unknown" constructor to avoid exposing its emptiness. The + // exception is if the pattern is at the top level, because we want empty matches to be + // considered exhaustive. + let is_secretly_empty = def.variants.is_empty() + && !cx.tcx.features().exhaustive_patterns + && !pcx.is_top_level; - if let ty::Adt(adt, substs) = pcx.ty.kind() { - if adt.is_enum() { - PatKind::Variant { - adt_def: adt, - substs, - variant_index: self.variant_index_for_adt(adt), - subpatterns, - } - } else { - PatKind::Leaf { subpatterns } - } - } else { - PatKind::Leaf { subpatterns } - } - } - // Note: given the expansion of `&str` patterns done in `expand_pattern`, we should - // be careful to reconstruct the correct constant pattern here. However a string - // literal pattern will never be reported as a non-exhaustiveness witness, so we - // can ignore this issue. - ty::Ref(..) => PatKind::Deref { subpattern: subpatterns.next().unwrap() }, - ty::Slice(_) | ty::Array(..) => bug!("bad slice pattern {:?} {:?}", self, pcx.ty), - _ => PatKind::Wild, - }, - Slice(slice) => match slice.kind { - FixedLen(_) => { - PatKind::Slice { prefix: subpatterns.collect(), slice: None, suffix: vec![] } - } - VarLen(prefix, _) => { - let mut prefix: Vec<_> = subpatterns.by_ref().take(prefix as usize).collect(); - if slice.array_len.is_some() { - // Improves diagnostics a bit: if the type is a known-size array, instead - // of reporting `[x, _, .., _, y]`, we prefer to report `[x, .., y]`. - // This is incorrect if the size is not known, since `[_, ..]` captures - // arrays of lengths `>= 1` whereas `[..]` captures any length. - while !prefix.is_empty() && prefix.last().unwrap().is_wildcard() { - prefix.pop(); - } - } - let suffix: Vec<_> = if slice.array_len.is_some() { - // Same as above. - subpatterns.skip_while(Pat::is_wildcard).collect() - } else { - subpatterns.collect() - }; - let wild = Pat::wildcard_from_ty(pcx.ty); - PatKind::Slice { prefix, slice: Some(wild), suffix } - } - }, - &Str(value) => PatKind::Constant { value }, - &FloatRange(lo, hi, end) => PatKind::Range(PatRange { lo, hi, end }), - IntRange(range) => return range.to_pat(pcx.cx.tcx), - NonExhaustive => PatKind::Wild, - Opaque => bug!("we should not try to apply an opaque constructor"), - Wildcard => bug!( - "trying to apply a wildcard constructor; this should have been done in `apply_constructors`" - ), - }; + if is_secretly_empty || is_declared_nonexhaustive { + vec![NonExhaustive] + } else if cx.tcx.features().exhaustive_patterns { + // If `exhaustive_patterns` is enabled, we exclude variants known to be + // uninhabited. + def.variants + .iter() + .filter(|v| { + !v.uninhabited_from(cx.tcx, substs, def.adt_kind(), cx.param_env) + .contains(cx.tcx, cx.module) + }) + .map(|v| Variant(v.def_id)) + .collect() + } else { + def.variants.iter().map(|v| Variant(v.def_id)).collect() + } + } + ty::Char => { + vec![ + // The valid Unicode Scalar Value ranges. + make_range('\u{0000}' as u128, '\u{D7FF}' as u128), + make_range('\u{E000}' as u128, '\u{10FFFF}' as u128), + ] + } + ty::Int(_) | ty::Uint(_) + if pcx.ty.is_ptr_sized_integral() + && !cx.tcx.features().precise_pointer_size_matching => + { + // `usize`/`isize` are not allowed to be matched exhaustively unless the + // `precise_pointer_size_matching` feature is enabled. So we treat those types like + // `#[non_exhaustive]` enums by returning a special unmatcheable constructor. + vec![NonExhaustive] + } + &ty::Int(ity) => { + let bits = Integer::from_attr(&cx.tcx, SignedInt(ity)).size().bits() as u128; + let min = 1u128 << (bits - 1); + let max = min - 1; + vec![make_range(min, max)] + } + &ty::Uint(uty) => { + let size = Integer::from_attr(&cx.tcx, UnsignedInt(uty)).size(); + let max = size.truncate(u128::MAX); + vec![make_range(0, max)] + } + // If `exhaustive_patterns` is disabled and our scrutinee is the never type, we cannot + // expose its emptiness. The exception is if the pattern is at the top level, because we + // want empty matches to be considered exhaustive. + ty::Never if !cx.tcx.features().exhaustive_patterns && !pcx.is_top_level => { + vec![NonExhaustive] + } + ty::Never => vec![], + _ if cx.is_uninhabited(pcx.ty) => vec![], + ty::Adt(..) | ty::Tuple(..) | ty::Ref(..) => vec![Single], + // This type is one for which we cannot list constructors, like `str` or `f64`. + _ => vec![NonExhaustive], + } +} - Pat { ty: pcx.ty, span: DUMMY_SP, kind: Box::new(pat) } +// A struct to compute a set of constructors equivalent to `all_ctors \ used_ctors`. +#[derive(Debug)] +pub(super) struct MissingConstructors<'tcx> { + all_ctors: SmallVec<[Constructor<'tcx>; 1]>, + used_ctors: Vec<Constructor<'tcx>>, +} + +impl<'tcx> MissingConstructors<'tcx> { + pub(super) fn new<'p>(pcx: PatCtxt<'_, 'p, 'tcx>) -> Self { + let used_ctors: Vec<Constructor<'_>> = + pcx.matrix.head_ctors(pcx.cx).cloned().filter(|c| !c.is_wildcard()).collect(); + // Since `all_ctors` never contains wildcards, this won't recurse further. + let all_ctors = + all_constructors(pcx).into_iter().flat_map(|ctor| ctor.split(pcx, None)).collect(); + + MissingConstructors { all_ctors, used_ctors } + } + + fn is_empty<'p>(&self, pcx: PatCtxt<'_, 'p, 'tcx>) -> bool { + self.iter(pcx).next().is_none() + } + + /// Iterate over all_ctors \ used_ctors + fn iter<'a, 'p>( + &'a self, + pcx: PatCtxt<'a, 'p, 'tcx>, + ) -> impl Iterator<Item = &'a Constructor<'tcx>> + Captures<'p> { + self.all_ctors.iter().filter(move |ctor| !ctor.is_covered_by_any(pcx, &self.used_ctors)) + } + + /// List the patterns corresponding to the missing constructors. In some cases, instead of + /// listing all constructors of a given type, we prefer to simply report a wildcard. + pub(super) fn report_patterns<'p>( + &self, + pcx: PatCtxt<'_, 'p, 'tcx>, + ) -> SmallVec<[Pat<'tcx>; 1]> { + // There are 2 ways we can report a witness here. + // Commonly, we can report all the "free" + // constructors as witnesses, e.g., if we have: + // + // ``` + // enum Direction { N, S, E, W } + // let Direction::N = ...; + // ``` + // + // we can report 3 witnesses: `S`, `E`, and `W`. + // + // However, there is a case where we don't want + // to do this and instead report a single `_` witness: + // if the user didn't actually specify a constructor + // in this arm, e.g., in + // + // ``` + // let x: (Direction, Direction, bool) = ...; + // let (_, _, false) = x; + // ``` + // + // we don't want to show all 16 possible witnesses + // `(<direction-1>, <direction-2>, true)` - we are + // satisfied with `(_, _, true)`. In this case, + // `used_ctors` is empty. + // The exception is: if we are at the top-level, for example in an empty match, we + // sometimes prefer reporting the list of constructors instead of just `_`. + let report_when_all_missing = pcx.is_top_level && !IntRange::is_integral(pcx.ty); + if self.used_ctors.is_empty() && !report_when_all_missing { + // All constructors are unused. Report only a wildcard + // rather than each individual constructor. + smallvec![Pat::wildcard_from_ty(pcx.ty)] + } else { + // Construct for each missing constructor a "wild" version of this + // constructor, that matches everything that can be built with + // it. For example, if `ctor` is a `Constructor::Variant` for + // `Option::Some`, we get the pattern `Some(_)`. + self.iter(pcx) + .map(|missing_ctor| Fields::wildcards(pcx, &missing_ctor).apply(pcx, missing_ctor)) + .collect() + } } } @@ -1077,7 +1020,7 @@ impl<'tcx> Constructor<'tcx> { /// `Fields` struct. This struct represents such a potentially-hidden field. When a field is hidden /// we still keep its type around. #[derive(Debug, Copy, Clone)] -enum FilteredField<'p, 'tcx> { +pub(super) enum FilteredField<'p, 'tcx> { Kept(&'p Pat<'tcx>), Hidden(Ty<'tcx>), } @@ -1110,7 +1053,7 @@ impl<'p, 'tcx> FilteredField<'p, 'tcx> { /// This filtering is uncommon in practice, because uninhabited fields are rarely used, so we avoid /// it when possible to preserve performance. #[derive(Debug, Clone)] -enum Fields<'p, 'tcx> { +pub(super) enum Fields<'p, 'tcx> { /// Lists of patterns that don't contain any filtered fields. /// `Slice` and `Vec` behave the same; the difference is only to avoid allocating and /// triple-dereferences when possible. Frankly this is premature optimization, I (Nadrieril) @@ -1147,7 +1090,7 @@ impl<'p, 'tcx> Fields<'p, 'tcx> { } /// Creates a new list of wildcard fields for a given constructor. - fn wildcards(pcx: PatCtxt<'_, 'p, 'tcx>, constructor: &Constructor<'tcx>) -> Self { + pub(super) fn wildcards(pcx: PatCtxt<'_, 'p, 'tcx>, constructor: &Constructor<'tcx>) -> Self { let ty = pcx.ty; let cx = pcx.cx; let wildcard_from_ty = |ty| &*cx.pattern_arena.alloc(Pat::wildcard_from_ty(ty)); @@ -1219,10 +1162,97 @@ impl<'p, 'tcx> Fields<'p, 'tcx> { ret } + /// Apply a constructor to a list of patterns, yielding a new pattern. `self` + /// must have as many elements as this constructor's arity. + /// + /// This is roughly the inverse of `specialize_constructor`. + /// + /// Examples: + /// `ctor`: `Constructor::Single` + /// `ty`: `Foo(u32, u32, u32)` + /// `self`: `[10, 20, _]` + /// returns `Foo(10, 20, _)` + /// + /// `ctor`: `Constructor::Variant(Option::Some)` + /// `ty`: `Option<bool>` + /// `self`: `[false]` + /// returns `Some(false)` + pub(super) fn apply(self, pcx: PatCtxt<'_, 'p, 'tcx>, ctor: &Constructor<'tcx>) -> Pat<'tcx> { + let mut subpatterns = self.all_patterns(); + + let pat = match ctor { + Single | Variant(_) => match pcx.ty.kind() { + ty::Adt(..) | ty::Tuple(..) => { + let subpatterns = subpatterns + .enumerate() + .map(|(i, p)| FieldPat { field: Field::new(i), pattern: p }) + .collect(); + + if let ty::Adt(adt, substs) = pcx.ty.kind() { + if adt.is_enum() { + PatKind::Variant { + adt_def: adt, + substs, + variant_index: ctor.variant_index_for_adt(adt), + subpatterns, + } + } else { + PatKind::Leaf { subpatterns } + } + } else { + PatKind::Leaf { subpatterns } + } + } + // Note: given the expansion of `&str` patterns done in `expand_pattern`, we should + // be careful to reconstruct the correct constant pattern here. However a string + // literal pattern will never be reported as a non-exhaustiveness witness, so we + // can ignore this issue. + ty::Ref(..) => PatKind::Deref { subpattern: subpatterns.next().unwrap() }, + ty::Slice(_) | ty::Array(..) => bug!("bad slice pattern {:?} {:?}", ctor, pcx.ty), + _ => PatKind::Wild, + }, + Slice(slice) => match slice.kind { + FixedLen(_) => { + PatKind::Slice { prefix: subpatterns.collect(), slice: None, suffix: vec![] } + } + VarLen(prefix, _) => { + let mut prefix: Vec<_> = subpatterns.by_ref().take(prefix as usize).collect(); + if slice.array_len.is_some() { + // Improves diagnostics a bit: if the type is a known-size array, instead + // of reporting `[x, _, .., _, y]`, we prefer to report `[x, .., y]`. + // This is incorrect if the size is not known, since `[_, ..]` captures + // arrays of lengths `>= 1` whereas `[..]` captures any length. + while !prefix.is_empty() && prefix.last().unwrap().is_wildcard() { + prefix.pop(); + } + } + let suffix: Vec<_> = if slice.array_len.is_some() { + // Same as above. + subpatterns.skip_while(Pat::is_wildcard).collect() + } else { + subpatterns.collect() + }; + let wild = Pat::wildcard_from_ty(pcx.ty); + PatKind::Slice { prefix, slice: Some(wild), suffix } + } + }, + &Str(value) => PatKind::Constant { value }, + &FloatRange(lo, hi, end) => PatKind::Range(PatRange { lo, hi, end }), + IntRange(range) => return range.to_pat(pcx.cx.tcx), + NonExhaustive => PatKind::Wild, + Opaque => bug!("we should not try to apply an opaque constructor"), + Wildcard => bug!( + "trying to apply a wildcard constructor; this should have been done in `apply_constructors`" + ), + }; + + Pat { ty: pcx.ty, span: DUMMY_SP, kind: Box::new(pat) } + } + /// Returns the number of patterns from the viewpoint of match-checking, i.e. excluding hidden /// fields. This is what we want in most cases in this file, the only exception being /// conversion to/from `Pat`. - fn len(&self) -> usize { + pub(super) fn len(&self) -> usize { match self { Fields::Slice(pats) => pats.len(), Fields::Vec(pats) => pats.len(), @@ -1243,6 +1273,18 @@ impl<'p, 'tcx> Fields<'p, 'tcx> { pats.into_iter() } + /// Returns the filtered list of patterns, not including hidden fields. + pub(super) fn filtered_patterns(self) -> SmallVec<[&'p Pat<'tcx>; 2]> { + match self { + Fields::Slice(pats) => pats.iter().collect(), + Fields::Vec(pats) => pats, + Fields::Filtered { fields, .. } => { + // We skip hidden fields here + fields.into_iter().filter_map(|p| p.kept()).collect() + } + } + } + /// Overrides some of the fields with the provided patterns. Exactly like /// `replace_fields_indexed`, except that it takes `FieldPat`s as input. fn replace_with_fieldpats( @@ -1288,7 +1330,7 @@ impl<'p, 'tcx> Fields<'p, 'tcx> { /// Replaces contained fields with the given filtered list of patterns, e.g. taken from the /// matrix. There must be `len()` patterns in `pats`. - fn replace_fields( + pub(super) fn replace_fields( &self, cx: &MatchCheckCtxt<'p, 'tcx>, pats: impl IntoIterator<Item = Pat<'tcx>>, @@ -1326,7 +1368,7 @@ impl<'p, 'tcx> Fields<'p, 'tcx> { /// } /// ``` /// This is guaranteed to preserve the number of patterns in `self`. - fn replace_with_pattern_arguments(&self, pat: &'p Pat<'tcx>) -> Self { + pub(super) fn replace_with_pattern_arguments(&self, pat: &'p Pat<'tcx>) -> Self { match pat.kind.as_ref() { PatKind::Deref { subpattern } => { assert_eq!(self.len(), 1); @@ -1349,1005 +1391,4 @@ impl<'p, 'tcx> Fields<'p, 'tcx> { _ => self.clone(), } } - - fn push_on_patstack(self, stack: &[&'p Pat<'tcx>]) -> PatStack<'p, 'tcx> { - let pats: SmallVec<_> = match self { - Fields::Slice(pats) => pats.iter().chain(stack.iter().copied()).collect(), - Fields::Vec(mut pats) => { - pats.extend_from_slice(stack); - pats - } - Fields::Filtered { fields, .. } => { - // We skip hidden fields here - fields.into_iter().filter_map(|p| p.kept()).chain(stack.iter().copied()).collect() - } - }; - PatStack::from_vec(pats) - } -} - -#[derive(Clone, Debug)] -crate enum Usefulness<'tcx> { - /// Carries, for each column in the matrix, a set of sub-branches that have been found to be - /// unreachable. Used only in the presence of or-patterns, otherwise it stays empty. - Useful(Vec<FxHashSet<Span>>), - /// Carries a list of witnesses of non-exhaustiveness. - UsefulWithWitness(Vec<Witness<'tcx>>), - NotUseful, -} - -impl<'tcx> Usefulness<'tcx> { - fn new_useful(preference: WitnessPreference) -> Self { - match preference { - ConstructWitness => UsefulWithWitness(vec![Witness(vec![])]), - LeaveOutWitness => Useful(vec![]), - } - } - - fn is_useful(&self) -> bool { - !matches!(*self, NotUseful) - } - - fn apply_constructor<'p>( - self, - pcx: PatCtxt<'_, 'p, 'tcx>, - ctor: &Constructor<'tcx>, - ctor_wild_subpatterns: &Fields<'p, 'tcx>, - ) -> Self { - match self { - UsefulWithWitness(witnesses) => { - let new_witnesses = if ctor.is_wildcard() { - let missing_ctors = MissingConstructors::new(pcx); - let new_patterns = missing_ctors.report_patterns(pcx); - witnesses - .into_iter() - .flat_map(|witness| { - new_patterns.iter().map(move |pat| { - let mut witness = witness.clone(); - witness.0.push(pat.clone()); - witness - }) - }) - .collect() - } else { - witnesses - .into_iter() - .map(|witness| witness.apply_constructor(pcx, &ctor, ctor_wild_subpatterns)) - .collect() - }; - UsefulWithWitness(new_witnesses) - } - Useful(mut unreachables) => { - if !unreachables.is_empty() { - // When we apply a constructor, there are `arity` columns of the matrix that - // corresponded to its arguments. All the unreachables found in these columns - // will, after `apply`, come from the first column. So we take the union of all - // the corresponding sets and put them in the first column. - // Note that `arity` may be 0, in which case we just push a new empty set. - let len = unreachables.len(); - let arity = ctor_wild_subpatterns.len(); - let mut unioned = FxHashSet::default(); - for set in unreachables.drain((len - arity)..) { - unioned.extend(set) - } - unreachables.push(unioned); - } - Useful(unreachables) - } - x => x, - } - } -} - -#[derive(Copy, Clone, Debug)] -enum WitnessPreference { - ConstructWitness, - LeaveOutWitness, -} - -#[derive(Copy, Clone)] -struct PatCtxt<'a, 'p, 'tcx> { - cx: &'a MatchCheckCtxt<'p, 'tcx>, - /// Current state of the matrix. - matrix: &'a Matrix<'p, 'tcx>, - /// Type of the current column under investigation. - ty: Ty<'tcx>, - /// Span of the current pattern under investigation. - span: Span, - /// Whether the current pattern is the whole pattern as found in a match arm, or if it's a - /// subpattern. - is_top_level: bool, -} - -/// A witness of non-exhaustiveness for error reporting, represented -/// as a list of patterns (in reverse order of construction) with -/// wildcards inside to represent elements that can take any inhabitant -/// of the type as a value. -/// -/// A witness against a list of patterns should have the same types -/// and length as the pattern matched against. Because Rust `match` -/// is always against a single pattern, at the end the witness will -/// have length 1, but in the middle of the algorithm, it can contain -/// multiple patterns. -/// -/// For example, if we are constructing a witness for the match against -/// -/// ``` -/// struct Pair(Option<(u32, u32)>, bool); -/// -/// match (p: Pair) { -/// Pair(None, _) => {} -/// Pair(_, false) => {} -/// } -/// ``` -/// -/// We'll perform the following steps: -/// 1. Start with an empty witness -/// `Witness(vec![])` -/// 2. Push a witness `Some(_)` against the `None` -/// `Witness(vec![Some(_)])` -/// 3. Push a witness `true` against the `false` -/// `Witness(vec![Some(_), true])` -/// 4. Apply the `Pair` constructor to the witnesses -/// `Witness(vec![Pair(Some(_), true)])` -/// -/// The final `Pair(Some(_), true)` is then the resulting witness. -#[derive(Clone, Debug)] -crate struct Witness<'tcx>(Vec<Pat<'tcx>>); - -impl<'tcx> Witness<'tcx> { - /// Asserts that the witness contains a single pattern, and returns it. - fn single_pattern(self) -> Pat<'tcx> { - assert_eq!(self.0.len(), 1); - self.0.into_iter().next().unwrap() - } - - /// Constructs a partial witness for a pattern given a list of - /// patterns expanded by the specialization step. - /// - /// When a pattern P is discovered to be useful, this function is used bottom-up - /// to reconstruct a complete witness, e.g., a pattern P' that covers a subset - /// of values, V, where each value in that set is not covered by any previously - /// used patterns and is covered by the pattern P'. Examples: - /// - /// left_ty: tuple of 3 elements - /// pats: [10, 20, _] => (10, 20, _) - /// - /// left_ty: struct X { a: (bool, &'static str), b: usize} - /// pats: [(false, "foo"), 42] => X { a: (false, "foo"), b: 42 } - fn apply_constructor<'p>( - mut self, - pcx: PatCtxt<'_, 'p, 'tcx>, - ctor: &Constructor<'tcx>, - ctor_wild_subpatterns: &Fields<'p, 'tcx>, - ) -> Self { - let pat = { - let len = self.0.len(); - let arity = ctor_wild_subpatterns.len(); - let pats = self.0.drain((len - arity)..).rev(); - let fields = ctor_wild_subpatterns.replace_fields(pcx.cx, pats); - ctor.apply(pcx, fields) - }; - - self.0.push(pat); - - self - } -} - -/// This determines the set of all possible constructors of a pattern matching -/// values of type `left_ty`. For vectors, this would normally be an infinite set -/// but is instead bounded by the maximum fixed length of slice patterns in -/// the column of patterns being analyzed. -/// -/// We make sure to omit constructors that are statically impossible. E.g., for -/// `Option<!>`, we do not include `Some(_)` in the returned list of constructors. -/// Invariant: this returns an empty `Vec` if and only if the type is uninhabited (as determined by -/// `cx.is_uninhabited()`). -fn all_constructors<'p, 'tcx>(pcx: PatCtxt<'_, 'p, 'tcx>) -> Vec<Constructor<'tcx>> { - debug!("all_constructors({:?})", pcx.ty); - let cx = pcx.cx; - let make_range = |start, end| { - IntRange( - // `unwrap()` is ok because we know the type is an integer. - IntRange::from_range(cx.tcx, start, end, pcx.ty, &RangeEnd::Included, pcx.span) - .unwrap(), - ) - }; - match pcx.ty.kind() { - ty::Bool => vec![make_range(0, 1)], - ty::Array(sub_ty, len) if len.try_eval_usize(cx.tcx, cx.param_env).is_some() => { - let len = len.eval_usize(cx.tcx, cx.param_env); - if len != 0 && cx.is_uninhabited(sub_ty) { - vec![] - } else { - vec![Slice(Slice::new(Some(len), VarLen(0, 0)))] - } - } - // Treat arrays of a constant but unknown length like slices. - ty::Array(sub_ty, _) | ty::Slice(sub_ty) => { - let kind = if cx.is_uninhabited(sub_ty) { FixedLen(0) } else { VarLen(0, 0) }; - vec![Slice(Slice::new(None, kind))] - } - ty::Adt(def, substs) if def.is_enum() => { - // If the enum is declared as `#[non_exhaustive]`, we treat it as if it had an - // additional "unknown" constructor. - // There is no point in enumerating all possible variants, because the user can't - // actually match against them all themselves. So we always return only the fictitious - // constructor. - // E.g., in an example like: - // - // ``` - // let err: io::ErrorKind = ...; - // match err { - // io::ErrorKind::NotFound => {}, - // } - // ``` - // - // we don't want to show every possible IO error, but instead have only `_` as the - // witness. - let is_declared_nonexhaustive = cx.is_foreign_non_exhaustive_enum(pcx.ty); - - // If `exhaustive_patterns` is disabled and our scrutinee is an empty enum, we treat it - // as though it had an "unknown" constructor to avoid exposing its emptiness. The - // exception is if the pattern is at the top level, because we want empty matches to be - // considered exhaustive. - let is_secretly_empty = def.variants.is_empty() - && !cx.tcx.features().exhaustive_patterns - && !pcx.is_top_level; - - if is_secretly_empty || is_declared_nonexhaustive { - vec![NonExhaustive] - } else if cx.tcx.features().exhaustive_patterns { - // If `exhaustive_patterns` is enabled, we exclude variants known to be - // uninhabited. - def.variants - .iter() - .filter(|v| { - !v.uninhabited_from(cx.tcx, substs, def.adt_kind(), cx.param_env) - .contains(cx.tcx, cx.module) - }) - .map(|v| Variant(v.def_id)) - .collect() - } else { - def.variants.iter().map(|v| Variant(v.def_id)).collect() - } - } - ty::Char => { - vec![ - // The valid Unicode Scalar Value ranges. - make_range('\u{0000}' as u128, '\u{D7FF}' as u128), - make_range('\u{E000}' as u128, '\u{10FFFF}' as u128), - ] - } - ty::Int(_) | ty::Uint(_) - if pcx.ty.is_ptr_sized_integral() - && !cx.tcx.features().precise_pointer_size_matching => - { - // `usize`/`isize` are not allowed to be matched exhaustively unless the - // `precise_pointer_size_matching` feature is enabled. So we treat those types like - // `#[non_exhaustive]` enums by returning a special unmatcheable constructor. - vec![NonExhaustive] - } - &ty::Int(ity) => { - let bits = Integer::from_attr(&cx.tcx, SignedInt(ity)).size().bits() as u128; - let min = 1u128 << (bits - 1); - let max = min - 1; - vec![make_range(min, max)] - } - &ty::Uint(uty) => { - let size = Integer::from_attr(&cx.tcx, UnsignedInt(uty)).size(); - let max = size.truncate(u128::MAX); - vec![make_range(0, max)] - } - // If `exhaustive_patterns` is disabled and our scrutinee is the never type, we cannot - // expose its emptiness. The exception is if the pattern is at the top level, because we - // want empty matches to be considered exhaustive. - ty::Never if !cx.tcx.features().exhaustive_patterns && !pcx.is_top_level => { - vec![NonExhaustive] - } - ty::Never => vec![], - _ if cx.is_uninhabited(pcx.ty) => vec![], - ty::Adt(..) | ty::Tuple(..) | ty::Ref(..) => vec![Single], - // This type is one for which we cannot list constructors, like `str` or `f64`. - _ => vec![NonExhaustive], - } -} - -/// An inclusive interval, used for precise integer exhaustiveness checking. -/// `IntRange`s always store a contiguous range. This means that values are -/// encoded such that `0` encodes the minimum value for the integer, -/// regardless of the signedness. -/// For example, the pattern `-128..=127i8` is encoded as `0..=255`. -/// This makes comparisons and arithmetic on interval endpoints much more -/// straightforward. See `signed_bias` for details. -/// -/// `IntRange` is never used to encode an empty range or a "range" that wraps -/// around the (offset) space: i.e., `range.lo <= range.hi`. -#[derive(Clone, Debug)] -struct IntRange<'tcx> { - range: RangeInclusive<u128>, - ty: Ty<'tcx>, - span: Span, -} - -impl<'tcx> IntRange<'tcx> { - #[inline] - fn is_integral(ty: Ty<'_>) -> bool { - matches!(ty.kind(), ty::Char | ty::Int(_) | ty::Uint(_) | ty::Bool) - } - - fn is_singleton(&self) -> bool { - self.range.start() == self.range.end() - } - - fn boundaries(&self) -> (u128, u128) { - (*self.range.start(), *self.range.end()) - } - - /// Don't treat `usize`/`isize` exhaustively unless the `precise_pointer_size_matching` feature - /// is enabled. - fn treat_exhaustively(&self, tcx: TyCtxt<'tcx>) -> bool { - !self.ty.is_ptr_sized_integral() || tcx.features().precise_pointer_size_matching - } - - #[inline] - fn integral_size_and_signed_bias(tcx: TyCtxt<'tcx>, ty: Ty<'_>) -> Option<(Size, u128)> { - match *ty.kind() { - ty::Bool => Some((Size::from_bytes(1), 0)), - ty::Char => Some((Size::from_bytes(4), 0)), - ty::Int(ity) => { - let size = Integer::from_attr(&tcx, SignedInt(ity)).size(); - Some((size, 1u128 << (size.bits() as u128 - 1))) - } - ty::Uint(uty) => Some((Integer::from_attr(&tcx, UnsignedInt(uty)).size(), 0)), - _ => None, - } - } - - #[inline] - fn from_const( - tcx: TyCtxt<'tcx>, - param_env: ty::ParamEnv<'tcx>, - value: &Const<'tcx>, - span: Span, - ) -> Option<IntRange<'tcx>> { - if let Some((target_size, bias)) = Self::integral_size_and_signed_bias(tcx, value.ty) { - let ty = value.ty; - let val = (|| { - if let ty::ConstKind::Value(ConstValue::Scalar(scalar)) = value.val { - // For this specific pattern we can skip a lot of effort and go - // straight to the result, after doing a bit of checking. (We - // could remove this branch and just fall through, which - // is more general but much slower.) - if let Ok(bits) = scalar.to_bits_or_ptr(target_size, &tcx) { - return Some(bits); - } - } - // This is a more general form of the previous case. - value.try_eval_bits(tcx, param_env, ty) - })()?; - let val = val ^ bias; - Some(IntRange { range: val..=val, ty, span }) - } else { - None - } - } - - #[inline] - fn from_range( - tcx: TyCtxt<'tcx>, - lo: u128, - hi: u128, - ty: Ty<'tcx>, - end: &RangeEnd, - span: Span, - ) -> Option<IntRange<'tcx>> { - if Self::is_integral(ty) { - // Perform a shift if the underlying types are signed, - // which makes the interval arithmetic simpler. - let bias = IntRange::signed_bias(tcx, ty); - let (lo, hi) = (lo ^ bias, hi ^ bias); - let offset = (*end == RangeEnd::Excluded) as u128; - if lo > hi || (lo == hi && *end == RangeEnd::Excluded) { - // This should have been caught earlier by E0030. - bug!("malformed range pattern: {}..={}", lo, (hi - offset)); - } - Some(IntRange { range: lo..=(hi - offset), ty, span }) - } else { - None - } - } - - // The return value of `signed_bias` should be XORed with an endpoint to encode/decode it. - fn signed_bias(tcx: TyCtxt<'tcx>, ty: Ty<'tcx>) -> u128 { - match *ty.kind() { - ty::Int(ity) => { - let bits = Integer::from_attr(&tcx, SignedInt(ity)).size().bits() as u128; - 1u128 << (bits - 1) - } - _ => 0, - } - } - - fn is_subrange(&self, other: &Self) -> bool { - other.range.start() <= self.range.start() && self.range.end() <= other.range.end() - } - - fn intersection(&self, tcx: TyCtxt<'tcx>, other: &Self) -> Option<Self> { - let ty = self.ty; - let (lo, hi) = self.boundaries(); - let (other_lo, other_hi) = other.boundaries(); - if self.treat_exhaustively(tcx) { - if lo <= other_hi && other_lo <= hi { - let span = other.span; - Some(IntRange { range: max(lo, other_lo)..=min(hi, other_hi), ty, span }) - } else { - None - } - } else { - // If the range should not be treated exhaustively, fallback to checking for inclusion. - if self.is_subrange(other) { Some(self.clone()) } else { None } - } - } - - fn suspicious_intersection(&self, other: &Self) -> bool { - // `false` in the following cases: - // 1 ---- // 1 ---------- // 1 ---- // 1 ---- - // 2 ---------- // 2 ---- // 2 ---- // 2 ---- - // - // The following are currently `false`, but could be `true` in the future (#64007): - // 1 --------- // 1 --------- - // 2 ---------- // 2 ---------- - // - // `true` in the following cases: - // 1 ------- // 1 ------- - // 2 -------- // 2 ------- - let (lo, hi) = self.boundaries(); - let (other_lo, other_hi) = other.boundaries(); - lo == other_hi || hi == other_lo - } - - fn to_pat(&self, tcx: TyCtxt<'tcx>) -> Pat<'tcx> { - let (lo, hi) = self.boundaries(); - - let bias = IntRange::signed_bias(tcx, self.ty); - let (lo, hi) = (lo ^ bias, hi ^ bias); - - let ty = ty::ParamEnv::empty().and(self.ty); - let lo_const = ty::Const::from_bits(tcx, lo, ty); - let hi_const = ty::Const::from_bits(tcx, hi, ty); - - let kind = if lo == hi { - PatKind::Constant { value: lo_const } - } else { - PatKind::Range(PatRange { lo: lo_const, hi: hi_const, end: RangeEnd::Included }) - }; - - // This is a brand new pattern, so we don't reuse `self.span`. - Pat { ty: self.ty, span: DUMMY_SP, kind: Box::new(kind) } - } - - /// For exhaustive integer matching, some constructors are grouped within other constructors - /// (namely integer typed values are grouped within ranges). However, when specialising these - /// constructors, we want to be specialising for the underlying constructors (the integers), not - /// the groups (the ranges). Thus we need to split the groups up. Splitting them up naïvely would - /// mean creating a separate constructor for every single value in the range, which is clearly - /// impractical. However, observe that for some ranges of integers, the specialisation will be - /// identical across all values in that range (i.e., there are equivalence classes of ranges of - /// constructors based on their `U(S(c, P), S(c, p))` outcome). These classes are grouped by - /// the patterns that apply to them (in the matrix `P`). We can split the range whenever the - /// patterns that apply to that range (specifically: the patterns that *intersect* with that range) - /// change. - /// Our solution, therefore, is to split the range constructor into subranges at every single point - /// the group of intersecting patterns changes (using the method described below). - /// And voilà ! We're testing precisely those ranges that we need to, without any exhaustive matching - /// on actual integers. The nice thing about this is that the number of subranges is linear in the - /// number of rows in the matrix (i.e., the number of cases in the `match` statement), so we don't - /// need to be worried about matching over gargantuan ranges. - /// - /// Essentially, given the first column of a matrix representing ranges, looking like the following: - /// - /// |------| |----------| |-------| || - /// |-------| |-------| |----| || - /// |---------| - /// - /// We split the ranges up into equivalence classes so the ranges are no longer overlapping: - /// - /// |--|--|||-||||--||---|||-------| |-|||| || - /// - /// The logic for determining how to split the ranges is fairly straightforward: we calculate - /// boundaries for each interval range, sort them, then create constructors for each new interval - /// between every pair of boundary points. (This essentially sums up to performing the intuitive - /// merging operation depicted above.) - fn split<'p>( - &self, - pcx: PatCtxt<'_, 'p, 'tcx>, - hir_id: Option<HirId>, - ) -> SmallVec<[Constructor<'tcx>; 1]> { - let ty = pcx.ty; - - /// Represents a border between 2 integers. Because the intervals spanning borders - /// must be able to cover every integer, we need to be able to represent - /// 2^128 + 1 such borders. - #[derive(Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Debug)] - enum Border { - JustBefore(u128), - AfterMax, - } - - // A function for extracting the borders of an integer interval. - fn range_borders(r: IntRange<'_>) -> impl Iterator<Item = Border> { - let (lo, hi) = r.range.into_inner(); - let from = Border::JustBefore(lo); - let to = match hi.checked_add(1) { - Some(m) => Border::JustBefore(m), - None => Border::AfterMax, - }; - vec![from, to].into_iter() - } - - // Collect the span and range of all the intersecting ranges to lint on likely - // incorrect range patterns. (#63987) - let mut overlaps = vec![]; - let row_len = pcx.matrix.patterns.get(0).map(|r| r.len()).unwrap_or(0); - // `borders` is the set of borders between equivalence classes: each equivalence - // class lies between 2 borders. - let row_borders = pcx - .matrix - .head_ctors(pcx.cx) - .filter_map(|ctor| ctor.as_int_range()) - .filter_map(|range| { - let intersection = self.intersection(pcx.cx.tcx, &range); - let should_lint = self.suspicious_intersection(&range); - if let (Some(range), 1, true) = (&intersection, row_len, should_lint) { - // FIXME: for now, only check for overlapping ranges on simple range - // patterns. Otherwise with the current logic the following is detected - // as overlapping: - // match (10u8, true) { - // (0 ..= 125, false) => {} - // (126 ..= 255, false) => {} - // (0 ..= 255, true) => {} - // } - overlaps.push(range.clone()); - } - intersection - }) - .flat_map(range_borders); - let self_borders = range_borders(self.clone()); - let mut borders: Vec<_> = row_borders.chain(self_borders).collect(); - borders.sort_unstable(); - - self.lint_overlapping_patterns(pcx.cx.tcx, hir_id, ty, overlaps); - - // We're going to iterate through every adjacent pair of borders, making sure that - // each represents an interval of nonnegative length, and convert each such - // interval into a constructor. - borders - .array_windows() - .filter_map(|&pair| match pair { - [Border::JustBefore(n), Border::JustBefore(m)] => { - if n < m { - Some(n..=(m - 1)) - } else { - None - } - } - [Border::JustBefore(n), Border::AfterMax] => Some(n..=u128::MAX), - [Border::AfterMax, _] => None, - }) - .map(|range| IntRange { range, ty, span: pcx.span }) - .map(IntRange) - .collect() - } - - fn lint_overlapping_patterns( - &self, - tcx: TyCtxt<'tcx>, - hir_id: Option<HirId>, - ty: Ty<'tcx>, - overlaps: Vec<IntRange<'tcx>>, - ) { - if let (true, Some(hir_id)) = (!overlaps.is_empty(), hir_id) { - tcx.struct_span_lint_hir( - lint::builtin::OVERLAPPING_PATTERNS, - hir_id, - self.span, - |lint| { - let mut err = lint.build("multiple patterns covering the same range"); - err.span_label(self.span, "overlapping patterns"); - for int_range in overlaps { - // Use the real type for user display of the ranges: - err.span_label( - int_range.span, - &format!( - "this range overlaps on `{}`", - IntRange { range: int_range.range, ty, span: DUMMY_SP }.to_pat(tcx), - ), - ); - } - err.emit(); - }, - ); - } - } - - /// See `Constructor::is_covered_by` - fn is_covered_by<'p>(&self, pcx: PatCtxt<'_, 'p, 'tcx>, other: &Self) -> bool { - if self.intersection(pcx.cx.tcx, other).is_some() { - // Constructor splitting should ensure that all intersections we encounter are actually - // inclusions. - assert!(self.is_subrange(other)); - true - } else { - false - } - } -} - -/// Ignore spans when comparing, they don't carry semantic information as they are only for lints. -impl<'tcx> std::cmp::PartialEq for IntRange<'tcx> { - fn eq(&self, other: &Self) -> bool { - self.range == other.range && self.ty == other.ty - } -} - -// A struct to compute a set of constructors equivalent to `all_ctors \ used_ctors`. -#[derive(Debug)] -struct MissingConstructors<'tcx> { - all_ctors: SmallVec<[Constructor<'tcx>; 1]>, - used_ctors: Vec<Constructor<'tcx>>, -} - -impl<'tcx> MissingConstructors<'tcx> { - fn new<'p>(pcx: PatCtxt<'_, 'p, 'tcx>) -> Self { - let used_ctors: Vec<Constructor<'_>> = - pcx.matrix.head_ctors(pcx.cx).cloned().filter(|c| !c.is_wildcard()).collect(); - // Since `all_ctors` never contains wildcards, this won't recurse further. - let all_ctors = - all_constructors(pcx).into_iter().flat_map(|ctor| ctor.split(pcx, None)).collect(); - - MissingConstructors { all_ctors, used_ctors } - } - - fn is_empty<'p>(&self, pcx: PatCtxt<'_, 'p, 'tcx>) -> bool { - self.iter(pcx).next().is_none() - } - - /// Iterate over all_ctors \ used_ctors - fn iter<'a, 'p>( - &'a self, - pcx: PatCtxt<'a, 'p, 'tcx>, - ) -> impl Iterator<Item = &'a Constructor<'tcx>> + Captures<'p> { - self.all_ctors.iter().filter(move |ctor| !ctor.is_covered_by_any(pcx, &self.used_ctors)) - } - - /// List the patterns corresponding to the missing constructors. In some cases, instead of - /// listing all constructors of a given type, we prefer to simply report a wildcard. - fn report_patterns<'p>(&self, pcx: PatCtxt<'_, 'p, 'tcx>) -> SmallVec<[Pat<'tcx>; 1]> { - // There are 2 ways we can report a witness here. - // Commonly, we can report all the "free" - // constructors as witnesses, e.g., if we have: - // - // ``` - // enum Direction { N, S, E, W } - // let Direction::N = ...; - // ``` - // - // we can report 3 witnesses: `S`, `E`, and `W`. - // - // However, there is a case where we don't want - // to do this and instead report a single `_` witness: - // if the user didn't actually specify a constructor - // in this arm, e.g., in - // - // ``` - // let x: (Direction, Direction, bool) = ...; - // let (_, _, false) = x; - // ``` - // - // we don't want to show all 16 possible witnesses - // `(<direction-1>, <direction-2>, true)` - we are - // satisfied with `(_, _, true)`. In this case, - // `used_ctors` is empty. - // The exception is: if we are at the top-level, for example in an empty match, we - // sometimes prefer reporting the list of constructors instead of just `_`. - let report_when_all_missing = pcx.is_top_level && !IntRange::is_integral(pcx.ty); - if self.used_ctors.is_empty() && !report_when_all_missing { - // All constructors are unused. Report only a wildcard - // rather than each individual constructor. - smallvec![Pat::wildcard_from_ty(pcx.ty)] - } else { - // Construct for each missing constructor a "wild" version of this - // constructor, that matches everything that can be built with - // it. For example, if `ctor` is a `Constructor::Variant` for - // `Option::Some`, we get the pattern `Some(_)`. - self.iter(pcx) - .map(|missing_ctor| { - let fields = Fields::wildcards(pcx, &missing_ctor); - missing_ctor.apply(pcx, fields) - }) - .collect() - } - } -} - -/// Algorithm from <http://moscova.inria.fr/~maranget/papers/warn/index.html>. -/// The algorithm from the paper has been modified to correctly handle empty -/// types. The changes are: -/// (0) We don't exit early if the pattern matrix has zero rows. We just -/// continue to recurse over columns. -/// (1) all_constructors will only return constructors that are statically -/// possible. E.g., it will only return `Ok` for `Result<T, !>`. -/// -/// This finds whether a (row) vector `v` of patterns is 'useful' in relation -/// to a set of such vectors `m` - this is defined as there being a set of -/// inputs that will match `v` but not any of the sets in `m`. -/// -/// All the patterns at each column of the `matrix ++ v` matrix must have the same type. -/// -/// This is used both for reachability checking (if a pattern isn't useful in -/// relation to preceding patterns, it is not reachable) and exhaustiveness -/// checking (if a wildcard pattern is useful in relation to a matrix, the -/// matrix isn't exhaustive). -/// -/// `is_under_guard` is used to inform if the pattern has a guard. If it -/// has one it must not be inserted into the matrix. This shouldn't be -/// relied on for soundness. -fn is_useful<'p, 'tcx>( - cx: &MatchCheckCtxt<'p, 'tcx>, - matrix: &Matrix<'p, 'tcx>, - v: &PatStack<'p, 'tcx>, - witness_preference: WitnessPreference, - hir_id: HirId, - is_under_guard: bool, - is_top_level: bool, -) -> Usefulness<'tcx> { - let Matrix { patterns: rows, .. } = matrix; - debug!("is_useful({:#?}, {:#?})", matrix, v); - - // The base case. We are pattern-matching on () and the return value is - // based on whether our matrix has a row or not. - // NOTE: This could potentially be optimized by checking rows.is_empty() - // first and then, if v is non-empty, the return value is based on whether - // the type of the tuple we're checking is inhabited or not. - if v.is_empty() { - return if rows.is_empty() { - Usefulness::new_useful(witness_preference) - } else { - NotUseful - }; - }; - - assert!(rows.iter().all(|r| r.len() == v.len())); - - // If the first pattern is an or-pattern, expand it. - if let Some(vs) = v.expand_or_pat() { - // We expand the or pattern, trying each of its branches in turn and keeping careful track - // of possible unreachable sub-branches. - // - // If two branches have detected some unreachable sub-branches, we need to be careful. If - // they were detected in columns that are not the current one, we want to keep only the - // sub-branches that were unreachable in _all_ branches. Eg. in the following, the last - // `true` is unreachable in the second branch of the first or-pattern, but not otherwise. - // Therefore we don't want to lint that it is unreachable. - // - // ``` - // match (true, true) { - // (true, true) => {} - // (false | true, false | true) => {} - // } - // ``` - // If however the sub-branches come from the current column, they come from the inside of - // the current or-pattern, and we want to keep them all. Eg. in the following, we _do_ want - // to lint that the last `false` is unreachable. - // ``` - // match None { - // Some(false) => {} - // None | Some(true | false) => {} - // } - // ``` - - let mut matrix = matrix.clone(); - // We keep track of sub-branches separately depending on whether they come from this column - // or from others. - let mut unreachables_this_column: FxHashSet<Span> = FxHashSet::default(); - let mut unreachables_other_columns: Vec<FxHashSet<Span>> = Vec::default(); - // Whether at least one branch is reachable. - let mut any_is_useful = false; - - for v in vs { - let res = is_useful(cx, &matrix, &v, witness_preference, hir_id, is_under_guard, false); - match res { - Useful(unreachables) => { - if let Some((this_column, other_columns)) = unreachables.split_last() { - // We keep the union of unreachables found in the first column. - unreachables_this_column.extend(this_column); - // We keep the intersection of unreachables found in other columns. - if unreachables_other_columns.is_empty() { - unreachables_other_columns = other_columns.to_vec(); - } else { - unreachables_other_columns = unreachables_other_columns - .into_iter() - .zip(other_columns) - .map(|(x, y)| x.intersection(&y).copied().collect()) - .collect(); - } - } - any_is_useful = true; - } - NotUseful => { - unreachables_this_column.insert(v.head().span); - } - UsefulWithWitness(_) => bug!( - "encountered or-pat in the expansion of `_` during exhaustiveness checking" - ), - } - - // If pattern has a guard don't add it to the matrix. - if !is_under_guard { - // We push the already-seen patterns into the matrix in order to detect redundant - // branches like `Some(_) | Some(0)`. - matrix.push(v); - } - } - - return if any_is_useful { - let mut unreachables = if unreachables_other_columns.is_empty() { - let n_columns = v.len(); - (0..n_columns - 1).map(|_| FxHashSet::default()).collect() - } else { - unreachables_other_columns - }; - unreachables.push(unreachables_this_column); - Useful(unreachables) - } else { - NotUseful - }; - } - - // FIXME(Nadrieril): Hack to work around type normalization issues (see #72476). - let ty = matrix.heads().next().map(|r| r.ty).unwrap_or(v.head().ty); - let pcx = PatCtxt { cx, matrix, ty, span: v.head().span, is_top_level }; - - debug!("is_useful_expand_first_col: ty={:#?}, expanding {:#?}", pcx.ty, v.head()); - - let ret = v - .head_ctor(cx) - .split(pcx, Some(hir_id)) - .into_iter() - .map(|ctor| { - // We cache the result of `Fields::wildcards` because it is used a lot. - let ctor_wild_subpatterns = Fields::wildcards(pcx, &ctor); - let matrix = pcx.matrix.specialize_constructor(pcx, &ctor, &ctor_wild_subpatterns); - let v = v.pop_head_constructor(&ctor_wild_subpatterns); - let usefulness = - is_useful(pcx.cx, &matrix, &v, witness_preference, hir_id, is_under_guard, false); - usefulness.apply_constructor(pcx, &ctor, &ctor_wild_subpatterns) - }) - .find(|result| result.is_useful()) - .unwrap_or(NotUseful); - debug!("is_useful::returns({:#?}, {:#?}) = {:?}", matrix, v, ret); - ret -} - -/// Determines the constructor that the given pattern can be specialized to. -/// Returns `None` in case of a catch-all, which can't be specialized. -fn pat_constructor<'p, 'tcx>( - cx: &MatchCheckCtxt<'p, 'tcx>, - pat: &'p Pat<'tcx>, -) -> Constructor<'tcx> { - match pat.kind.as_ref() { - PatKind::AscribeUserType { .. } => bug!(), // Handled by `expand_pattern` - PatKind::Binding { .. } | PatKind::Wild => Wildcard, - PatKind::Leaf { .. } | PatKind::Deref { .. } => Single, - &PatKind::Variant { adt_def, variant_index, .. } => { - Variant(adt_def.variants[variant_index].def_id) - } - PatKind::Constant { value } => { - if let Some(int_range) = IntRange::from_const(cx.tcx, cx.param_env, value, pat.span) { - IntRange(int_range) - } else { - match pat.ty.kind() { - ty::Float(_) => FloatRange(value, value, RangeEnd::Included), - // In `expand_pattern`, we convert string literals to `&CONST` patterns with - // `CONST` a pattern of type `str`. In truth this contains a constant of type - // `&str`. - ty::Str => Str(value), - // All constants that can be structurally matched have already been expanded - // into the corresponding `Pat`s by `const_to_pat`. Constants that remain are - // opaque. - _ => Opaque, - } - } - } - &PatKind::Range(PatRange { lo, hi, end }) => { - let ty = lo.ty; - if let Some(int_range) = IntRange::from_range( - cx.tcx, - lo.eval_bits(cx.tcx, cx.param_env, lo.ty), - hi.eval_bits(cx.tcx, cx.param_env, hi.ty), - ty, - &end, - pat.span, - ) { - IntRange(int_range) - } else { - FloatRange(lo, hi, end) - } - } - PatKind::Array { prefix, slice, suffix } | PatKind::Slice { prefix, slice, suffix } => { - let array_len = match pat.ty.kind() { - ty::Array(_, length) => Some(length.eval_usize(cx.tcx, cx.param_env)), - ty::Slice(_) => None, - _ => span_bug!(pat.span, "bad ty {:?} for slice pattern", pat.ty), - }; - let prefix = prefix.len() as u64; - let suffix = suffix.len() as u64; - let kind = - if slice.is_some() { VarLen(prefix, suffix) } else { FixedLen(prefix + suffix) }; - Slice(Slice::new(array_len, kind)) - } - PatKind::Or { .. } => bug!("Or-pattern should have been expanded earlier on."), - } -} - -/// The arm of a match expression. -#[derive(Clone, Copy)] -crate struct MatchArm<'p, 'tcx> { - /// The pattern must have been lowered through `MatchVisitor::lower_pattern`. - crate pat: &'p super::Pat<'tcx>, - crate hir_id: HirId, - crate has_guard: bool, -} - -/// The output of checking a match for exhaustiveness and arm reachability. -crate struct UsefulnessReport<'p, 'tcx> { - /// For each arm of the input, whether that arm is reachable after the arms above it. - crate arm_usefulness: Vec<(MatchArm<'p, 'tcx>, Usefulness<'tcx>)>, - /// If the match is exhaustive, this is empty. If not, this contains witnesses for the lack of - /// exhaustiveness. - crate non_exhaustiveness_witnesses: Vec<super::Pat<'tcx>>, -} - -/// The entrypoint for the usefulness algorithm. Computes whether a match is exhaustive and which -/// of its arms are reachable. -/// -/// Note: the input patterns must have been lowered through `MatchVisitor::lower_pattern`. -crate fn compute_match_usefulness<'p, 'tcx>( - cx: &MatchCheckCtxt<'p, 'tcx>, - arms: &[MatchArm<'p, 'tcx>], - scrut_hir_id: HirId, - scrut_ty: Ty<'tcx>, -) -> UsefulnessReport<'p, 'tcx> { - let mut matrix = Matrix::empty(); - let arm_usefulness: Vec<_> = arms - .iter() - .copied() - .map(|arm| { - let v = PatStack::from_pattern(arm.pat); - let usefulness = - is_useful(cx, &matrix, &v, LeaveOutWitness, arm.hir_id, arm.has_guard, true); - if !arm.has_guard { - matrix.push(v); - } - (arm, usefulness) - }) - .collect(); - - let wild_pattern = cx.pattern_arena.alloc(super::Pat::wildcard_from_ty(scrut_ty)); - let v = PatStack::from_pattern(wild_pattern); - let usefulness = is_useful(cx, &matrix, &v, ConstructWitness, scrut_hir_id, false, true); - let non_exhaustiveness_witnesses = match usefulness { - NotUseful => vec![], // Wildcard pattern isn't useful, so the match is exhaustive. - UsefulWithWitness(pats) => { - if pats.is_empty() { - bug!("Exhaustiveness check returned no witnesses") - } else { - pats.into_iter().map(|w| w.single_pattern()).collect() - } - } - Useful(_) => bug!(), - }; - UsefulnessReport { arm_usefulness, non_exhaustiveness_witnesses } } diff --git a/compiler/rustc_mir_build/src/thir/pattern/mod.rs b/compiler/rustc_mir_build/src/thir/pattern/mod.rs index db0ecd701bc..7e9a3a37278 100644 --- a/compiler/rustc_mir_build/src/thir/pattern/mod.rs +++ b/compiler/rustc_mir_build/src/thir/pattern/mod.rs @@ -1,8 +1,9 @@ //! Validation of patterns/matches. -mod _match; mod check_match; mod const_to_pat; +mod deconstruct_pat; +mod usefulness; pub(crate) use self::check_match::check_match; diff --git a/compiler/rustc_mir_build/src/thir/pattern/usefulness.rs b/compiler/rustc_mir_build/src/thir/pattern/usefulness.rs new file mode 100644 index 00000000000..be96d5ae816 --- /dev/null +++ b/compiler/rustc_mir_build/src/thir/pattern/usefulness.rs @@ -0,0 +1,992 @@ +//! Note: tests specific to this file can be found in: +//! +//! - `ui/pattern/usefulness` +//! - `ui/or-patterns` +//! - `ui/consts/const_in_pattern` +//! - `ui/rfc-2008-non-exhaustive` +//! - `ui/half-open-range-patterns` +//! - probably many others +//! +//! I (Nadrieril) prefer to put new tests in `ui/pattern/usefulness` unless there's a specific +//! reason not to, for example if they depend on a particular feature like `or_patterns`. +//! +//! ----- +//! +//! This file includes the logic for exhaustiveness and usefulness checking for +//! pattern-matching. Specifically, given a list of patterns for a type, we can +//! tell whether: +//! (a) the patterns cover every possible constructor for the type (exhaustiveness) +//! (b) each pattern is necessary (usefulness) +//! +//! The algorithm implemented here is a modified version of the one described in +//! [this paper](http://moscova.inria.fr/~maranget/papers/warn/index.html). +//! However, to save future implementors from reading the original paper, we +//! summarise the algorithm here to hopefully save time and be a little clearer +//! (without being so rigorous). +//! +//! # Premise +//! +//! The core of the algorithm revolves about a "usefulness" check. In particular, we +//! are trying to compute a predicate `U(P, p)` where `P` is a list of patterns (we refer to this as +//! a matrix). `U(P, p)` represents whether, given an existing list of patterns +//! `P_1 ..= P_m`, adding a new pattern `p` will be "useful" (that is, cover previously- +//! uncovered values of the type). +//! +//! If we have this predicate, then we can easily compute both exhaustiveness of an +//! entire set of patterns and the individual usefulness of each one. +//! (a) the set of patterns is exhaustive iff `U(P, _)` is false (i.e., adding a wildcard +//! match doesn't increase the number of values we're matching) +//! (b) a pattern `P_i` is not useful if `U(P[0..=(i-1), P_i)` is false (i.e., adding a +//! pattern to those that have come before it doesn't increase the number of values +//! we're matching). +//! +//! # Core concept +//! +//! The idea that powers everything that is done in this file is the following: a value is made +//! from a constructor applied to some fields. Examples of constructors are `Some`, `None`, `(,)` +//! (the 2-tuple constructor), `Foo {..}` (the constructor for a struct `Foo`), and `2` (the +//! constructor for the number `2`). Fields are just a (possibly empty) list of values. +//! +//! Some of the constructors listed above might feel weird: `None` and `2` don't take any +//! arguments. This is part of what makes constructors so general: we will consider plain values +//! like numbers and string literals to be constructors that take no arguments, also called "0-ary +//! constructors"; they are the simplest case of constructors. This allows us to see any value as +//! made up from a tree of constructors, each having a given number of children. For example: +//! `(None, Ok(0))` is made from 4 different constructors. +//! +//! This idea can be extended to patterns: a pattern captures a set of possible values, and we can +//! describe this set using constructors. For example, `Err(_)` captures all values of the type +//! `Result<T, E>` that start with the `Err` constructor (for some choice of `T` and `E`). The +//! wildcard `_` captures all values of the given type starting with any of the constructors for +//! that type. +//! +//! We use this to compute whether different patterns might capture a same value. Do the patterns +//! `Ok("foo")` and `Err(_)` capture a common value? The answer is no, because the first pattern +//! captures only values starting with the `Ok` constructor and the second only values starting +//! with the `Err` constructor. Do the patterns `Some(42)` and `Some(1..10)` intersect? They might, +//! since they both capture values starting with `Some`. To be certain, we need to dig under the +//! `Some` constructor and continue asking the question. This is the main idea behind the +//! exhaustiveness algorithm: by looking at patterns constructor-by-constructor, we can efficiently +//! figure out if some new pattern might capture a value that hadn't been captured by previous +//! patterns. +//! +//! Constructors are represented by the `Constructor` enum, and its fields by the `Fields` enum. +//! Most of the complexity of this file resides in transforming between patterns and +//! (`Constructor`, `Fields`) pairs, handling all the special cases correctly. +//! +//! Caveat: this constructors/fields distinction doesn't quite cover every Rust value. For example +//! a value of type `Rc<u64>` doesn't fit this idea very well, nor do various other things. +//! However, this idea covers most of the cases that are relevant to exhaustiveness checking. +//! +//! +//! # Algorithm +//! +//! Recall that `U(P, p)` represents whether, given an existing list of patterns (aka matrix) `P`, +//! adding a new pattern `p` will cover previously-uncovered values of the type. +//! During the course of the algorithm, the rows of the matrix won't just be individual patterns, +//! but rather partially-deconstructed patterns in the form of a list of fields. The paper +//! calls those pattern-vectors, and we will call them pattern-stacks. The same holds for the +//! new pattern `p`. +//! +//! For example, say we have the following: +//! +//! ``` +//! // x: (Option<bool>, Result<()>) +//! match x { +//! (Some(true), _) => {} +//! (None, Err(())) => {} +//! (None, Err(_)) => {} +//! } +//! ``` +//! +//! Here, the matrix `P` starts as: +//! +//! ``` +//! [ +//! [(Some(true), _)], +//! [(None, Err(()))], +//! [(None, Err(_))], +//! ] +//! ``` +//! +//! We can tell it's not exhaustive, because `U(P, _)` is true (we're not covering +//! `[(Some(false), _)]`, for instance). In addition, row 3 is not useful, because +//! all the values it covers are already covered by row 2. +//! +//! A list of patterns can be thought of as a stack, because we are mainly interested in the top of +//! the stack at any given point, and we can pop or apply constructors to get new pattern-stacks. +//! To match the paper, the top of the stack is at the beginning / on the left. +//! +//! There are two important operations on pattern-stacks necessary to understand the algorithm: +//! +//! 1. We can pop a given constructor off the top of a stack. This operation is called +//! `specialize`, and is denoted `S(c, p)` where `c` is a constructor (like `Some` or +//! `None`) and `p` a pattern-stack. +//! If the pattern on top of the stack can cover `c`, this removes the constructor and +//! pushes its arguments onto the stack. It also expands OR-patterns into distinct patterns. +//! Otherwise the pattern-stack is discarded. +//! This essentially filters those pattern-stacks whose top covers the constructor `c` and +//! discards the others. +//! +//! For example, the first pattern above initially gives a stack `[(Some(true), _)]`. If we +//! pop the tuple constructor, we are left with `[Some(true), _]`, and if we then pop the +//! `Some` constructor we get `[true, _]`. If we had popped `None` instead, we would get +//! nothing back. +//! +//! This returns zero or more new pattern-stacks, as follows. We look at the pattern `p_1` +//! on top of the stack, and we have four cases: +//! +//! 1.1. `p_1 = c(r_1, .., r_a)`, i.e. the top of the stack has constructor `c`. We +//! push onto the stack the arguments of this constructor, and return the result: +//! `r_1, .., r_a, p_2, .., p_n` +//! +//! 1.2. `p_1 = c'(r_1, .., r_a')` where `c ≠c'`. We discard the current stack and +//! return nothing. +//! +//! 1.3. `p_1 = _`. We push onto the stack as many wildcards as the constructor `c` has +//! arguments (its arity), and return the resulting stack: +//! `_, .., _, p_2, .., p_n` +//! +//! 1.4. `p_1 = r_1 | r_2`. We expand the OR-pattern and then recurse on each resulting +//! stack: +//! - `S(c, (r_1, p_2, .., p_n))` +//! - `S(c, (r_2, p_2, .., p_n))` +//! +//! 2. We can pop a wildcard off the top of the stack. This is called `S(_, p)`, where `p` is +//! a pattern-stack. Note: the paper calls this `D(p)`. +//! This is used when we know there are missing constructor cases, but there might be +//! existing wildcard patterns, so to check the usefulness of the matrix, we have to check +//! all its *other* components. +//! +//! It is computed as follows. We look at the pattern `p_1` on top of the stack, +//! and we have three cases: +//! 2.1. `p_1 = c(r_1, .., r_a)`. We discard the current stack and return nothing. +//! 2.2. `p_1 = _`. We return the rest of the stack: +//! p_2, .., p_n +//! 2.3. `p_1 = r_1 | r_2`. We expand the OR-pattern and then recurse on each resulting +//! stack. +//! - `S(_, (r_1, p_2, .., p_n))` +//! - `S(_, (r_2, p_2, .., p_n))` +//! +//! Note that the OR-patterns are not always used directly in Rust, but are used to derive the +//! exhaustive integer matching rules, so they're written here for posterity. +//! +//! Both those operations extend straightforwardly to a list or pattern-stacks, i.e. a matrix, by +//! working row-by-row. Popping a constructor ends up keeping only the matrix rows that start with +//! the given constructor, and popping a wildcard keeps those rows that start with a wildcard. +//! +//! +//! The algorithm for computing `U` +//! ------------------------------- +//! The algorithm is inductive (on the number of columns: i.e., components of tuple patterns). +//! That means we're going to check the components from left-to-right, so the algorithm +//! operates principally on the first component of the matrix and new pattern-stack `p`. +//! This algorithm is realised in the `is_useful` function. +//! +//! Base case. (`n = 0`, i.e., an empty tuple pattern) +//! - If `P` already contains an empty pattern (i.e., if the number of patterns `m > 0`), +//! then `U(P, p)` is false. +//! - Otherwise, `P` must be empty, so `U(P, p)` is true. +//! +//! Inductive step. (`n > 0`, i.e., whether there's at least one column +//! [which may then be expanded into further columns later]) +//! We're going to match on the top of the new pattern-stack, `p_1`. +//! - If `p_1 == c(r_1, .., r_a)`, i.e. we have a constructor pattern. +//! Then, the usefulness of `p_1` can be reduced to whether it is useful when +//! we ignore all the patterns in the first column of `P` that involve other constructors. +//! This is where `S(c, P)` comes in: +//! `U(P, p) := U(S(c, P), S(c, p))` +//! +//! For example, if `P` is: +//! +//! ``` +//! [ +//! [Some(true), _], +//! [None, 0], +//! ] +//! ``` +//! +//! and `p` is `[Some(false), 0]`, then we don't care about row 2 since we know `p` only +//! matches values that row 2 doesn't. For row 1 however, we need to dig into the +//! arguments of `Some` to know whether some new value is covered. So we compute +//! `U([[true, _]], [false, 0])`. +//! +//! - If `p_1 == _`, then we look at the list of constructors that appear in the first +//! component of the rows of `P`: +//! + If there are some constructors that aren't present, then we might think that the +//! wildcard `_` is useful, since it covers those constructors that weren't covered +//! before. +//! That's almost correct, but only works if there were no wildcards in those first +//! components. So we need to check that `p` is useful with respect to the rows that +//! start with a wildcard, if there are any. This is where `S(_, x)` comes in: +//! `U(P, p) := U(S(_, P), S(_, p))` +//! +//! For example, if `P` is: +//! +//! ``` +//! [ +//! [_, true, _], +//! [None, false, 1], +//! ] +//! ``` +//! +//! and `p` is `[_, false, _]`, the `Some` constructor doesn't appear in `P`. So if we +//! only had row 2, we'd know that `p` is useful. However row 1 starts with a +//! wildcard, so we need to check whether `U([[true, _]], [false, 1])`. +//! +//! + Otherwise, all possible constructors (for the relevant type) are present. In this +//! case we must check whether the wildcard pattern covers any unmatched value. For +//! that, we can think of the `_` pattern as a big OR-pattern that covers all +//! possible constructors. For `Option`, that would mean `_ = None | Some(_)` for +//! example. The wildcard pattern is useful in this case if it is useful when +//! specialized to one of the possible constructors. So we compute: +//! `U(P, p) := ∃(k ϵ constructors) U(S(k, P), S(k, p))` +//! +//! For example, if `P` is: +//! +//! ``` +//! [ +//! [Some(true), _], +//! [None, false], +//! ] +//! ``` +//! +//! and `p` is `[_, false]`, both `None` and `Some` constructors appear in the first +//! components of `P`. We will therefore try popping both constructors in turn: we +//! compute `U([[true, _]], [_, false])` for the `Some` constructor, and `U([[false]], +//! [false])` for the `None` constructor. The first case returns true, so we know that +//! `p` is useful for `P`. Indeed, it matches `[Some(false), _]` that wasn't matched +//! before. +//! +//! - If `p_1 == r_1 | r_2`, then the usefulness depends on each `r_i` separately: +//! `U(P, p) := U(P, (r_1, p_2, .., p_n)) +//! || U(P, (r_2, p_2, .., p_n))` +//! +//! Modifications to the algorithm +//! ------------------------------ +//! The algorithm in the paper doesn't cover some of the special cases that arise in Rust, for +//! example uninhabited types and variable-length slice patterns. These are drawn attention to +//! throughout the code below. I'll make a quick note here about how exhaustive integer matching is +//! accounted for, though. +//! +//! Exhaustive integer matching +//! --------------------------- +//! An integer type can be thought of as a (huge) sum type: 1 | 2 | 3 | ... +//! So to support exhaustive integer matching, we can make use of the logic in the paper for +//! OR-patterns. However, we obviously can't just treat ranges x..=y as individual sums, because +//! they are likely gigantic. So we instead treat ranges as constructors of the integers. This means +//! that we have a constructor *of* constructors (the integers themselves). We then need to work +//! through all the inductive step rules above, deriving how the ranges would be treated as +//! OR-patterns, and making sure that they're treated in the same way even when they're ranges. +//! There are really only four special cases here: +//! - When we match on a constructor that's actually a range, we have to treat it as if we would +//! an OR-pattern. +//! + It turns out that we can simply extend the case for single-value patterns in +//! `specialize` to either be *equal* to a value constructor, or *contained within* a range +//! constructor. +//! + When the pattern itself is a range, you just want to tell whether any of the values in +//! the pattern range coincide with values in the constructor range, which is precisely +//! intersection. +//! Since when encountering a range pattern for a value constructor, we also use inclusion, it +//! means that whenever the constructor is a value/range and the pattern is also a value/range, +//! we can simply use intersection to test usefulness. +//! - When we're testing for usefulness of a pattern and the pattern's first component is a +//! wildcard. +//! + If all the constructors appear in the matrix, we have a slight complication. By default, +//! the behaviour (i.e., a disjunction over specialised matrices for each constructor) is +//! invalid, because we want a disjunction over every *integer* in each range, not just a +//! disjunction over every range. This is a bit more tricky to deal with: essentially we need +//! to form equivalence classes of subranges of the constructor range for which the behaviour +//! of the matrix `P` and new pattern `p` are the same. This is described in more +//! detail in `Constructor::split`. +//! + If some constructors are missing from the matrix, it turns out we don't need to do +//! anything special (because we know none of the integers are actually wildcards: i.e., we +//! can't span wildcards using ranges). + +use self::Usefulness::*; +use self::WitnessPreference::*; + +use super::deconstruct_pat::{Constructor, Fields, MissingConstructors}; +use super::{Pat, PatKind}; +use super::{PatternFoldable, PatternFolder}; + +use rustc_data_structures::captures::Captures; +use rustc_data_structures::fx::FxHashSet; +use rustc_data_structures::sync::OnceCell; + +use rustc_arena::TypedArena; +use rustc_hir::def_id::DefId; +use rustc_hir::HirId; +use rustc_middle::ty::{self, Ty, TyCtxt}; +use rustc_span::Span; + +use smallvec::{smallvec, SmallVec}; +use std::fmt; +use std::iter::{FromIterator, IntoIterator}; + +crate struct MatchCheckCtxt<'a, 'tcx> { + crate tcx: TyCtxt<'tcx>, + /// The module in which the match occurs. This is necessary for + /// checking inhabited-ness of types because whether a type is (visibly) + /// inhabited can depend on whether it was defined in the current module or + /// not. E.g., `struct Foo { _private: ! }` cannot be seen to be empty + /// outside its module and should not be matchable with an empty match statement. + crate module: DefId, + crate param_env: ty::ParamEnv<'tcx>, + crate pattern_arena: &'a TypedArena<Pat<'tcx>>, +} + +impl<'a, 'tcx> MatchCheckCtxt<'a, 'tcx> { + pub(super) fn is_uninhabited(&self, ty: Ty<'tcx>) -> bool { + if self.tcx.features().exhaustive_patterns { + self.tcx.is_ty_uninhabited_from(self.module, ty, self.param_env) + } else { + false + } + } + + /// Returns whether the given type is an enum from another crate declared `#[non_exhaustive]`. + pub(super) fn is_foreign_non_exhaustive_enum(&self, ty: Ty<'tcx>) -> bool { + match ty.kind() { + ty::Adt(def, ..) => { + def.is_enum() && def.is_variant_list_non_exhaustive() && !def.did.is_local() + } + _ => false, + } + } +} + +#[derive(Copy, Clone)] +pub(super) struct PatCtxt<'a, 'p, 'tcx> { + pub(super) cx: &'a MatchCheckCtxt<'p, 'tcx>, + /// Current state of the matrix. + pub(super) matrix: &'a Matrix<'p, 'tcx>, + /// Type of the current column under investigation. + pub(super) ty: Ty<'tcx>, + /// Span of the current pattern under investigation. + pub(super) span: Span, + /// Whether the current pattern is the whole pattern as found in a match arm, or if it's a + /// subpattern. + pub(super) is_top_level: bool, +} + +crate fn expand_pattern<'tcx>(pat: Pat<'tcx>) -> Pat<'tcx> { + LiteralExpander.fold_pattern(&pat) +} + +struct LiteralExpander; + +impl<'tcx> PatternFolder<'tcx> for LiteralExpander { + fn fold_pattern(&mut self, pat: &Pat<'tcx>) -> Pat<'tcx> { + debug!("fold_pattern {:?} {:?} {:?}", pat, pat.ty.kind(), pat.kind); + match (pat.ty.kind(), pat.kind.as_ref()) { + (_, PatKind::Binding { subpattern: Some(s), .. }) => s.fold_with(self), + (_, PatKind::AscribeUserType { subpattern: s, .. }) => s.fold_with(self), + (ty::Ref(_, t, _), PatKind::Constant { .. }) if t.is_str() => { + // Treat string literal patterns as deref patterns to a `str` constant, i.e. + // `&CONST`. This expands them like other const patterns. This could have been done + // in `const_to_pat`, but that causes issues with the rest of the matching code. + let mut new_pat = pat.super_fold_with(self); + // Make a fake const pattern of type `str` (instead of `&str`). That the carried + // constant value still knows it is of type `&str`. + new_pat.ty = t; + Pat { + kind: Box::new(PatKind::Deref { subpattern: new_pat }), + span: pat.span, + ty: pat.ty, + } + } + _ => pat.super_fold_with(self), + } + } +} + +impl<'tcx> Pat<'tcx> { + pub(super) fn is_wildcard(&self) -> bool { + matches!(*self.kind, PatKind::Binding { subpattern: None, .. } | PatKind::Wild) + } +} + +/// A row of a matrix. Rows of len 1 are very common, which is why `SmallVec[_; 2]` +/// works well. +#[derive(Debug, Clone)] +struct PatStack<'p, 'tcx> { + pats: SmallVec<[&'p Pat<'tcx>; 2]>, + /// Cache for the constructor of the head + head_ctor: OnceCell<Constructor<'tcx>>, +} + +impl<'p, 'tcx> PatStack<'p, 'tcx> { + fn from_pattern(pat: &'p Pat<'tcx>) -> Self { + Self::from_vec(smallvec![pat]) + } + + fn from_vec(vec: SmallVec<[&'p Pat<'tcx>; 2]>) -> Self { + PatStack { pats: vec, head_ctor: OnceCell::new() } + } + + fn is_empty(&self) -> bool { + self.pats.is_empty() + } + + fn len(&self) -> usize { + self.pats.len() + } + + fn head(&self) -> &'p Pat<'tcx> { + self.pats[0] + } + + fn head_ctor<'a>(&'a self, cx: &MatchCheckCtxt<'p, 'tcx>) -> &'a Constructor<'tcx> { + self.head_ctor.get_or_init(|| Constructor::from_pat(cx, self.head())) + } + + fn iter(&self) -> impl Iterator<Item = &Pat<'tcx>> { + self.pats.iter().copied() + } + + // If the first pattern is an or-pattern, expand this pattern. Otherwise, return `None`. + fn expand_or_pat(&self) -> Option<Vec<Self>> { + if self.is_empty() { + None + } else if let PatKind::Or { pats } = &*self.head().kind { + Some( + pats.iter() + .map(|pat| { + let mut new_patstack = PatStack::from_pattern(pat); + new_patstack.pats.extend_from_slice(&self.pats[1..]); + new_patstack + }) + .collect(), + ) + } else { + None + } + } + + /// This computes `S(self.head_ctor(), self)`. See top of the file for explanations. + /// + /// Structure patterns with a partial wild pattern (Foo { a: 42, .. }) have their missing + /// fields filled with wild patterns. + /// + /// This is roughly the inverse of `Constructor::apply`. + fn pop_head_constructor(&self, ctor_wild_subpatterns: &Fields<'p, 'tcx>) -> PatStack<'p, 'tcx> { + // We pop the head pattern and push the new fields extracted from the arguments of + // `self.head()`. + let mut new_fields = + ctor_wild_subpatterns.replace_with_pattern_arguments(self.head()).filtered_patterns(); + new_fields.extend_from_slice(&self.pats[1..]); + PatStack::from_vec(new_fields) + } +} + +impl<'p, 'tcx> Default for PatStack<'p, 'tcx> { + fn default() -> Self { + Self::from_vec(smallvec![]) + } +} + +impl<'p, 'tcx> PartialEq for PatStack<'p, 'tcx> { + fn eq(&self, other: &Self) -> bool { + self.pats == other.pats + } +} + +impl<'p, 'tcx> FromIterator<&'p Pat<'tcx>> for PatStack<'p, 'tcx> { + fn from_iter<T>(iter: T) -> Self + where + T: IntoIterator<Item = &'p Pat<'tcx>>, + { + Self::from_vec(iter.into_iter().collect()) + } +} + +/// A 2D matrix. +#[derive(Clone, PartialEq)] +pub(super) struct Matrix<'p, 'tcx> { + patterns: Vec<PatStack<'p, 'tcx>>, +} + +impl<'p, 'tcx> Matrix<'p, 'tcx> { + fn empty() -> Self { + Matrix { patterns: vec![] } + } + + /// Number of columns of this matrix. `None` is the matrix is empty. + pub(super) fn column_count(&self) -> Option<usize> { + self.patterns.get(0).map(|r| r.len()) + } + + /// Pushes a new row to the matrix. If the row starts with an or-pattern, this expands it. + fn push(&mut self, row: PatStack<'p, 'tcx>) { + if let Some(rows) = row.expand_or_pat() { + for row in rows { + // We recursively expand the or-patterns of the new rows. + // This is necessary as we might have `0 | (1 | 2)` or e.g., `x @ 0 | x @ (1 | 2)`. + self.push(row) + } + } else { + self.patterns.push(row); + } + } + + /// Iterate over the first component of each row + fn heads<'a>(&'a self) -> impl Iterator<Item = &'a Pat<'tcx>> + Captures<'p> { + self.patterns.iter().map(|r| r.head()) + } + + /// Iterate over the first constructor of each row + pub(super) fn head_ctors<'a>( + &'a self, + cx: &'a MatchCheckCtxt<'p, 'tcx>, + ) -> impl Iterator<Item = &'a Constructor<'tcx>> + Captures<'a> + Captures<'p> { + self.patterns.iter().map(move |r| r.head_ctor(cx)) + } + + /// This computes `S(constructor, self)`. See top of the file for explanations. + fn specialize_constructor( + &self, + pcx: PatCtxt<'_, 'p, 'tcx>, + ctor: &Constructor<'tcx>, + ctor_wild_subpatterns: &Fields<'p, 'tcx>, + ) -> Matrix<'p, 'tcx> { + self.patterns + .iter() + .filter(|r| ctor.is_covered_by(pcx, r.head_ctor(pcx.cx))) + .map(|r| r.pop_head_constructor(ctor_wild_subpatterns)) + .collect() + } +} + +/// Pretty-printer for matrices of patterns, example: +/// +/// ```text +/// +++++++++++++++++++++++++++++ +/// + _ + [] + +/// +++++++++++++++++++++++++++++ +/// + true + [First] + +/// +++++++++++++++++++++++++++++ +/// + true + [Second(true)] + +/// +++++++++++++++++++++++++++++ +/// + false + [_] + +/// +++++++++++++++++++++++++++++ +/// + _ + [_, _, tail @ ..] + +/// +++++++++++++++++++++++++++++ +/// ``` +impl<'p, 'tcx> fmt::Debug for Matrix<'p, 'tcx> { + fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { + write!(f, "\n")?; + + let Matrix { patterns: m, .. } = self; + let pretty_printed_matrix: Vec<Vec<String>> = + m.iter().map(|row| row.iter().map(|pat| format!("{:?}", pat)).collect()).collect(); + + let column_count = m.iter().map(|row| row.len()).max().unwrap_or(0); + assert!(m.iter().all(|row| row.len() == column_count)); + let column_widths: Vec<usize> = (0..column_count) + .map(|col| pretty_printed_matrix.iter().map(|row| row[col].len()).max().unwrap_or(0)) + .collect(); + + let total_width = column_widths.iter().cloned().sum::<usize>() + column_count * 3 + 1; + let br = "+".repeat(total_width); + write!(f, "{}\n", br)?; + for row in pretty_printed_matrix { + write!(f, "+")?; + for (column, pat_str) in row.into_iter().enumerate() { + write!(f, " ")?; + write!(f, "{:1$}", pat_str, column_widths[column])?; + write!(f, " +")?; + } + write!(f, "\n")?; + write!(f, "{}\n", br)?; + } + Ok(()) + } +} + +impl<'p, 'tcx> FromIterator<PatStack<'p, 'tcx>> for Matrix<'p, 'tcx> { + fn from_iter<T>(iter: T) -> Self + where + T: IntoIterator<Item = PatStack<'p, 'tcx>>, + { + let mut matrix = Matrix::empty(); + for x in iter { + // Using `push` ensures we correctly expand or-patterns. + matrix.push(x); + } + matrix + } +} + +#[derive(Clone, Debug)] +crate enum Usefulness<'tcx> { + /// Carries, for each column in the matrix, a set of sub-branches that have been found to be + /// unreachable. Used only in the presence of or-patterns, otherwise it stays empty. + Useful(Vec<FxHashSet<Span>>), + /// Carries a list of witnesses of non-exhaustiveness. + UsefulWithWitness(Vec<Witness<'tcx>>), + NotUseful, +} + +impl<'tcx> Usefulness<'tcx> { + fn new_useful(preference: WitnessPreference) -> Self { + match preference { + ConstructWitness => UsefulWithWitness(vec![Witness(vec![])]), + LeaveOutWitness => Useful(vec![]), + } + } + + fn is_useful(&self) -> bool { + !matches!(*self, NotUseful) + } + + fn apply_constructor<'p>( + self, + pcx: PatCtxt<'_, 'p, 'tcx>, + ctor: &Constructor<'tcx>, + ctor_wild_subpatterns: &Fields<'p, 'tcx>, + ) -> Self { + match self { + UsefulWithWitness(witnesses) => { + let new_witnesses = if ctor.is_wildcard() { + let missing_ctors = MissingConstructors::new(pcx); + let new_patterns = missing_ctors.report_patterns(pcx); + witnesses + .into_iter() + .flat_map(|witness| { + new_patterns.iter().map(move |pat| { + let mut witness = witness.clone(); + witness.0.push(pat.clone()); + witness + }) + }) + .collect() + } else { + witnesses + .into_iter() + .map(|witness| witness.apply_constructor(pcx, &ctor, ctor_wild_subpatterns)) + .collect() + }; + UsefulWithWitness(new_witnesses) + } + Useful(mut unreachables) => { + if !unreachables.is_empty() { + // When we apply a constructor, there are `arity` columns of the matrix that + // corresponded to its arguments. All the unreachables found in these columns + // will, after `apply`, come from the first column. So we take the union of all + // the corresponding sets and put them in the first column. + // Note that `arity` may be 0, in which case we just push a new empty set. + let len = unreachables.len(); + let arity = ctor_wild_subpatterns.len(); + let mut unioned = FxHashSet::default(); + for set in unreachables.drain((len - arity)..) { + unioned.extend(set) + } + unreachables.push(unioned); + } + Useful(unreachables) + } + x => x, + } + } +} + +#[derive(Copy, Clone, Debug)] +enum WitnessPreference { + ConstructWitness, + LeaveOutWitness, +} + +/// A witness of non-exhaustiveness for error reporting, represented +/// as a list of patterns (in reverse order of construction) with +/// wildcards inside to represent elements that can take any inhabitant +/// of the type as a value. +/// +/// A witness against a list of patterns should have the same types +/// and length as the pattern matched against. Because Rust `match` +/// is always against a single pattern, at the end the witness will +/// have length 1, but in the middle of the algorithm, it can contain +/// multiple patterns. +/// +/// For example, if we are constructing a witness for the match against +/// +/// ``` +/// struct Pair(Option<(u32, u32)>, bool); +/// +/// match (p: Pair) { +/// Pair(None, _) => {} +/// Pair(_, false) => {} +/// } +/// ``` +/// +/// We'll perform the following steps: +/// 1. Start with an empty witness +/// `Witness(vec![])` +/// 2. Push a witness `Some(_)` against the `None` +/// `Witness(vec![Some(_)])` +/// 3. Push a witness `true` against the `false` +/// `Witness(vec![Some(_), true])` +/// 4. Apply the `Pair` constructor to the witnesses +/// `Witness(vec![Pair(Some(_), true)])` +/// +/// The final `Pair(Some(_), true)` is then the resulting witness. +#[derive(Clone, Debug)] +crate struct Witness<'tcx>(Vec<Pat<'tcx>>); + +impl<'tcx> Witness<'tcx> { + /// Asserts that the witness contains a single pattern, and returns it. + fn single_pattern(self) -> Pat<'tcx> { + assert_eq!(self.0.len(), 1); + self.0.into_iter().next().unwrap() + } + + /// Constructs a partial witness for a pattern given a list of + /// patterns expanded by the specialization step. + /// + /// When a pattern P is discovered to be useful, this function is used bottom-up + /// to reconstruct a complete witness, e.g., a pattern P' that covers a subset + /// of values, V, where each value in that set is not covered by any previously + /// used patterns and is covered by the pattern P'. Examples: + /// + /// left_ty: tuple of 3 elements + /// pats: [10, 20, _] => (10, 20, _) + /// + /// left_ty: struct X { a: (bool, &'static str), b: usize} + /// pats: [(false, "foo"), 42] => X { a: (false, "foo"), b: 42 } + fn apply_constructor<'p>( + mut self, + pcx: PatCtxt<'_, 'p, 'tcx>, + ctor: &Constructor<'tcx>, + ctor_wild_subpatterns: &Fields<'p, 'tcx>, + ) -> Self { + let pat = { + let len = self.0.len(); + let arity = ctor_wild_subpatterns.len(); + let pats = self.0.drain((len - arity)..).rev(); + ctor_wild_subpatterns.replace_fields(pcx.cx, pats).apply(pcx, ctor) + }; + + self.0.push(pat); + + self + } +} + +/// Algorithm from <http://moscova.inria.fr/~maranget/papers/warn/index.html>. +/// The algorithm from the paper has been modified to correctly handle empty +/// types. The changes are: +/// (0) We don't exit early if the pattern matrix has zero rows. We just +/// continue to recurse over columns. +/// (1) all_constructors will only return constructors that are statically +/// possible. E.g., it will only return `Ok` for `Result<T, !>`. +/// +/// This finds whether a (row) vector `v` of patterns is 'useful' in relation +/// to a set of such vectors `m` - this is defined as there being a set of +/// inputs that will match `v` but not any of the sets in `m`. +/// +/// All the patterns at each column of the `matrix ++ v` matrix must have the same type. +/// +/// This is used both for reachability checking (if a pattern isn't useful in +/// relation to preceding patterns, it is not reachable) and exhaustiveness +/// checking (if a wildcard pattern is useful in relation to a matrix, the +/// matrix isn't exhaustive). +/// +/// `is_under_guard` is used to inform if the pattern has a guard. If it +/// has one it must not be inserted into the matrix. This shouldn't be +/// relied on for soundness. +fn is_useful<'p, 'tcx>( + cx: &MatchCheckCtxt<'p, 'tcx>, + matrix: &Matrix<'p, 'tcx>, + v: &PatStack<'p, 'tcx>, + witness_preference: WitnessPreference, + hir_id: HirId, + is_under_guard: bool, + is_top_level: bool, +) -> Usefulness<'tcx> { + let Matrix { patterns: rows, .. } = matrix; + debug!("is_useful({:#?}, {:#?})", matrix, v); + + // The base case. We are pattern-matching on () and the return value is + // based on whether our matrix has a row or not. + // NOTE: This could potentially be optimized by checking rows.is_empty() + // first and then, if v is non-empty, the return value is based on whether + // the type of the tuple we're checking is inhabited or not. + if v.is_empty() { + return if rows.is_empty() { + Usefulness::new_useful(witness_preference) + } else { + NotUseful + }; + }; + + assert!(rows.iter().all(|r| r.len() == v.len())); + + // If the first pattern is an or-pattern, expand it. + if let Some(vs) = v.expand_or_pat() { + // We expand the or pattern, trying each of its branches in turn and keeping careful track + // of possible unreachable sub-branches. + // + // If two branches have detected some unreachable sub-branches, we need to be careful. If + // they were detected in columns that are not the current one, we want to keep only the + // sub-branches that were unreachable in _all_ branches. Eg. in the following, the last + // `true` is unreachable in the second branch of the first or-pattern, but not otherwise. + // Therefore we don't want to lint that it is unreachable. + // + // ``` + // match (true, true) { + // (true, true) => {} + // (false | true, false | true) => {} + // } + // ``` + // If however the sub-branches come from the current column, they come from the inside of + // the current or-pattern, and we want to keep them all. Eg. in the following, we _do_ want + // to lint that the last `false` is unreachable. + // ``` + // match None { + // Some(false) => {} + // None | Some(true | false) => {} + // } + // ``` + + let mut matrix = matrix.clone(); + // We keep track of sub-branches separately depending on whether they come from this column + // or from others. + let mut unreachables_this_column: FxHashSet<Span> = FxHashSet::default(); + let mut unreachables_other_columns: Vec<FxHashSet<Span>> = Vec::default(); + // Whether at least one branch is reachable. + let mut any_is_useful = false; + + for v in vs { + let res = is_useful(cx, &matrix, &v, witness_preference, hir_id, is_under_guard, false); + match res { + Useful(unreachables) => { + if let Some((this_column, other_columns)) = unreachables.split_last() { + // We keep the union of unreachables found in the first column. + unreachables_this_column.extend(this_column); + // We keep the intersection of unreachables found in other columns. + if unreachables_other_columns.is_empty() { + unreachables_other_columns = other_columns.to_vec(); + } else { + unreachables_other_columns = unreachables_other_columns + .into_iter() + .zip(other_columns) + .map(|(x, y)| x.intersection(&y).copied().collect()) + .collect(); + } + } + any_is_useful = true; + } + NotUseful => { + unreachables_this_column.insert(v.head().span); + } + UsefulWithWitness(_) => bug!( + "encountered or-pat in the expansion of `_` during exhaustiveness checking" + ), + } + + // If pattern has a guard don't add it to the matrix. + if !is_under_guard { + // We push the already-seen patterns into the matrix in order to detect redundant + // branches like `Some(_) | Some(0)`. + matrix.push(v); + } + } + + return if any_is_useful { + let mut unreachables = if unreachables_other_columns.is_empty() { + let n_columns = v.len(); + (0..n_columns - 1).map(|_| FxHashSet::default()).collect() + } else { + unreachables_other_columns + }; + unreachables.push(unreachables_this_column); + Useful(unreachables) + } else { + NotUseful + }; + } + + // FIXME(Nadrieril): Hack to work around type normalization issues (see #72476). + let ty = matrix.heads().next().map(|r| r.ty).unwrap_or(v.head().ty); + let pcx = PatCtxt { cx, matrix, ty, span: v.head().span, is_top_level }; + + debug!("is_useful_expand_first_col: ty={:#?}, expanding {:#?}", pcx.ty, v.head()); + + let ret = v + .head_ctor(cx) + .split(pcx, Some(hir_id)) + .into_iter() + .map(|ctor| { + // We cache the result of `Fields::wildcards` because it is used a lot. + let ctor_wild_subpatterns = Fields::wildcards(pcx, &ctor); + let matrix = pcx.matrix.specialize_constructor(pcx, &ctor, &ctor_wild_subpatterns); + let v = v.pop_head_constructor(&ctor_wild_subpatterns); + let usefulness = + is_useful(pcx.cx, &matrix, &v, witness_preference, hir_id, is_under_guard, false); + usefulness.apply_constructor(pcx, &ctor, &ctor_wild_subpatterns) + }) + .find(|result| result.is_useful()) + .unwrap_or(NotUseful); + debug!("is_useful::returns({:#?}, {:#?}) = {:?}", matrix, v, ret); + ret +} + +/// The arm of a match expression. +#[derive(Clone, Copy)] +crate struct MatchArm<'p, 'tcx> { + /// The pattern must have been lowered through `MatchVisitor::lower_pattern`. + crate pat: &'p super::Pat<'tcx>, + crate hir_id: HirId, + crate has_guard: bool, +} + +/// The output of checking a match for exhaustiveness and arm reachability. +crate struct UsefulnessReport<'p, 'tcx> { + /// For each arm of the input, whether that arm is reachable after the arms above it. + crate arm_usefulness: Vec<(MatchArm<'p, 'tcx>, Usefulness<'tcx>)>, + /// If the match is exhaustive, this is empty. If not, this contains witnesses for the lack of + /// exhaustiveness. + crate non_exhaustiveness_witnesses: Vec<super::Pat<'tcx>>, +} + +/// The entrypoint for the usefulness algorithm. Computes whether a match is exhaustive and which +/// of its arms are reachable. +/// +/// Note: the input patterns must have been lowered through `MatchVisitor::lower_pattern`. +crate fn compute_match_usefulness<'p, 'tcx>( + cx: &MatchCheckCtxt<'p, 'tcx>, + arms: &[MatchArm<'p, 'tcx>], + scrut_hir_id: HirId, + scrut_ty: Ty<'tcx>, +) -> UsefulnessReport<'p, 'tcx> { + let mut matrix = Matrix::empty(); + let arm_usefulness: Vec<_> = arms + .iter() + .copied() + .map(|arm| { + let v = PatStack::from_pattern(arm.pat); + let usefulness = + is_useful(cx, &matrix, &v, LeaveOutWitness, arm.hir_id, arm.has_guard, true); + if !arm.has_guard { + matrix.push(v); + } + (arm, usefulness) + }) + .collect(); + + let wild_pattern = cx.pattern_arena.alloc(super::Pat::wildcard_from_ty(scrut_ty)); + let v = PatStack::from_pattern(wild_pattern); + let usefulness = is_useful(cx, &matrix, &v, ConstructWitness, scrut_hir_id, false, true); + let non_exhaustiveness_witnesses = match usefulness { + NotUseful => vec![], // Wildcard pattern isn't useful, so the match is exhaustive. + UsefulWithWitness(pats) => { + if pats.is_empty() { + bug!("Exhaustiveness check returned no witnesses") + } else { + pats.into_iter().map(|w| w.single_pattern()).collect() + } + } + Useful(_) => bug!(), + }; + UsefulnessReport { arm_usefulness, non_exhaustiveness_witnesses } +} diff --git a/compiler/rustc_parse/src/lib.rs b/compiler/rustc_parse/src/lib.rs index 8a6b0230023..44999c9b63a 100644 --- a/compiler/rustc_parse/src/lib.rs +++ b/compiler/rustc_parse/src/lib.rs @@ -6,15 +6,18 @@ #![feature(or_patterns)] use rustc_ast as ast; +use rustc_ast::attr::HasAttrs; use rustc_ast::token::{self, DelimToken, Nonterminal, Token, TokenKind}; use rustc_ast::tokenstream::{self, LazyTokenStream, TokenStream, TokenTree}; use rustc_ast_pretty::pprust; +use rustc_data_structures::fx::FxHashSet; use rustc_data_structures::sync::Lrc; use rustc_errors::{Diagnostic, FatalError, Level, PResult}; use rustc_session::parse::ParseSess; use rustc_span::{symbol::kw, FileName, SourceFile, Span, DUMMY_SP}; use smallvec::SmallVec; +use std::cell::RefCell; use std::mem; use std::path::Path; use std::str; @@ -249,29 +252,23 @@ pub fn nt_to_tokenstream(nt: &Nonterminal, sess: &ParseSess, span: Span) -> Toke // before we fall back to the stringification. let convert_tokens = - |tokens: &Option<LazyTokenStream>| tokens.as_ref().map(|t| t.create_token_stream()); + |tokens: Option<&LazyTokenStream>| tokens.as_ref().map(|t| t.create_token_stream()); let tokens = match *nt { Nonterminal::NtItem(ref item) => prepend_attrs(&item.attrs, item.tokens.as_ref()), - Nonterminal::NtBlock(ref block) => convert_tokens(&block.tokens), - Nonterminal::NtStmt(ref stmt) => { - // FIXME: We currently only collect tokens for `:stmt` - // matchers in `macro_rules!` macros. When we start collecting - // tokens for attributes on statements, we will need to prepend - // attributes here - convert_tokens(&stmt.tokens) - } - Nonterminal::NtPat(ref pat) => convert_tokens(&pat.tokens), - Nonterminal::NtTy(ref ty) => convert_tokens(&ty.tokens), + Nonterminal::NtBlock(ref block) => convert_tokens(block.tokens.as_ref()), + Nonterminal::NtStmt(ref stmt) => prepend_attrs(stmt.attrs(), stmt.tokens()), + Nonterminal::NtPat(ref pat) => convert_tokens(pat.tokens.as_ref()), + Nonterminal::NtTy(ref ty) => convert_tokens(ty.tokens.as_ref()), Nonterminal::NtIdent(ident, is_raw) => { Some(tokenstream::TokenTree::token(token::Ident(ident.name, is_raw), ident.span).into()) } Nonterminal::NtLifetime(ident) => { Some(tokenstream::TokenTree::token(token::Lifetime(ident.name), ident.span).into()) } - Nonterminal::NtMeta(ref attr) => convert_tokens(&attr.tokens), - Nonterminal::NtPath(ref path) => convert_tokens(&path.tokens), - Nonterminal::NtVis(ref vis) => convert_tokens(&vis.tokens), + Nonterminal::NtMeta(ref attr) => convert_tokens(attr.tokens.as_ref()), + Nonterminal::NtPath(ref path) => convert_tokens(path.tokens.as_ref()), + Nonterminal::NtVis(ref vis) => convert_tokens(vis.tokens.as_ref()), Nonterminal::NtTT(ref tt) => Some(tt.clone().into()), Nonterminal::NtExpr(ref expr) | Nonterminal::NtLiteral(ref expr) => { if expr.tokens.is_none() { @@ -281,6 +278,25 @@ pub fn nt_to_tokenstream(nt: &Nonterminal, sess: &ParseSess, span: Span) -> Toke } }; + // Caches the stringification of 'good' `TokenStreams` which passed + // `tokenstream_probably_equal_for_proc_macro`. This allows us to avoid + // repeatedly stringifying and comparing the same `TokenStream` for deeply + // nested nonterminals. + // + // We cache by the strinification instead of the `TokenStream` to avoid + // needing to implement `Hash` for `TokenStream`. Note that it's possible to + // have two distinct `TokenStream`s that stringify to the same result + // (e.g. if they differ only in hygiene information). However, any + // information lost during the stringification process is also intentionally + // ignored by `tokenstream_probably_equal_for_proc_macro`, so it's fine + // that a single cache entry may 'map' to multiple distinct `TokenStream`s. + // + // This is a temporary hack to prevent compilation blowup on certain inputs. + // The entire pretty-print/retokenize process will be removed soon. + thread_local! { + static GOOD_TOKEN_CACHE: RefCell<FxHashSet<String>> = Default::default(); + } + // FIXME(#43081): Avoid this pretty-print + reparse hack // Pretty-print the AST struct without inserting any parenthesis // beyond those explicitly written by the user (e.g. `ExpnKind::Paren`). @@ -288,7 +304,7 @@ pub fn nt_to_tokenstream(nt: &Nonterminal, sess: &ParseSess, span: Span) -> Toke // ever used for a comparison against the capture tokenstream. let source = pprust::nonterminal_to_string_no_extra_parens(nt); let filename = FileName::macro_expansion_source_code(&source); - let reparsed_tokens = parse_stream_from_source_str(filename, source, sess, Some(span)); + let reparsed_tokens = parse_stream_from_source_str(filename, source.clone(), sess, Some(span)); // During early phases of the compiler the AST could get modified // directly (e.g., attributes added or removed) and the internal cache @@ -314,8 +330,13 @@ pub fn nt_to_tokenstream(nt: &Nonterminal, sess: &ParseSess, span: Span) -> Toke // modifications, including adding/removing typically non-semantic // tokens such as extra braces and commas, don't happen. if let Some(tokens) = tokens { + if GOOD_TOKEN_CACHE.with(|cache| cache.borrow().contains(&source)) { + return tokens; + } + // Compare with a non-relaxed delim match to start. if tokenstream_probably_equal_for_proc_macro(&tokens, &reparsed_tokens, sess, false) { + GOOD_TOKEN_CACHE.with(|cache| cache.borrow_mut().insert(source.clone())); return tokens; } @@ -324,6 +345,11 @@ pub fn nt_to_tokenstream(nt: &Nonterminal, sess: &ParseSess, span: Span) -> Toke // token stream to match up with inserted parenthesis in the reparsed stream. let source_with_parens = pprust::nonterminal_to_string(nt); let filename_with_parens = FileName::macro_expansion_source_code(&source_with_parens); + + if GOOD_TOKEN_CACHE.with(|cache| cache.borrow().contains(&source_with_parens)) { + return tokens; + } + let reparsed_tokens_with_parens = parse_stream_from_source_str( filename_with_parens, source_with_parens, @@ -339,6 +365,7 @@ pub fn nt_to_tokenstream(nt: &Nonterminal, sess: &ParseSess, span: Span) -> Toke sess, true, ) { + GOOD_TOKEN_CACHE.with(|cache| cache.borrow_mut().insert(source.clone())); return tokens; } @@ -418,9 +445,9 @@ pub fn tokenstream_probably_equal_for_proc_macro( // to iterate breaking tokens mutliple times. For example: // '[BinOpEq(Shr)] => [Gt, Ge] -> [Gt, Gt, Eq]' let mut token_trees: SmallVec<[_; 2]>; - if let TokenTree::Token(token) = &tree { + if let TokenTree::Token(token) = tree { let mut out = SmallVec::<[_; 2]>::new(); - out.push(token.clone()); + out.push(token); // Iterate to fixpoint: // * We start off with 'out' containing our initial token, and `temp` empty // * If we are able to break any tokens in `out`, then `out` will have diff --git a/compiler/rustc_parse/src/parser/attr.rs b/compiler/rustc_parse/src/parser/attr.rs index 41985757b57..fae09fa6fec 100644 --- a/compiler/rustc_parse/src/parser/attr.rs +++ b/compiler/rustc_parse/src/parser/attr.rs @@ -8,8 +8,9 @@ use rustc_span::{sym, Span}; use tracing::debug; +// Public for rustfmt usage #[derive(Debug)] -pub(super) enum InnerAttrPolicy<'a> { +pub enum InnerAttrPolicy<'a> { Permitted, Forbidden { reason: &'a str, saw_doc_comment: bool, prev_attr_sp: Option<Span> }, } @@ -78,7 +79,8 @@ impl<'a> Parser<'a> { /// Matches `attribute = # ! [ meta_item ]`. /// `inner_parse_policy` prescribes how to handle inner attributes. - fn parse_attribute( + // Public for rustfmt usage. + pub fn parse_attribute( &mut self, inner_parse_policy: InnerAttrPolicy<'_>, ) -> PResult<'a, ast::Attribute> { diff --git a/compiler/rustc_parse/src/parser/mod.rs b/compiler/rustc_parse/src/parser/mod.rs index 40aa2db58c7..b746256f5fe 100644 --- a/compiler/rustc_parse/src/parser/mod.rs +++ b/compiler/rustc_parse/src/parser/mod.rs @@ -873,7 +873,8 @@ impl<'a> Parser<'a> { id: DUMMY_NODE_ID, value: self.mk_expr(blk.span, ExprKind::Block(blk, None), AttrVec::new()), }; - Ok(self.mk_expr(span, ExprKind::ConstBlock(anon_const), AttrVec::new())) + let blk_span = anon_const.value.span; + Ok(self.mk_expr(span.to(blk_span), ExprKind::ConstBlock(anon_const), AttrVec::new())) } /// Parses mutability (`mut` or nothing). @@ -1213,14 +1214,20 @@ impl<'a> Parser<'a> { // // This also makes `Parser` very cheap to clone, since // there is no intermediate collection buffer to clone. + #[derive(Clone)] struct LazyTokenStreamImpl { start_token: (Token, Spacing), cursor_snapshot: TokenCursor, num_calls: usize, desugar_doc_comments: bool, + trailing_semi: bool, } impl CreateTokenStream for LazyTokenStreamImpl { fn create_token_stream(&self) -> TokenStream { + let mut num_calls = self.num_calls; + if self.trailing_semi { + num_calls += 1; + } // The token produced by the final call to `next` or `next_desugared` // was not actually consumed by the callback. The combination // of chaining the initial token and using `take` produces the desired @@ -1228,17 +1235,25 @@ impl<'a> Parser<'a> { // and omit the final token otherwise. let mut cursor_snapshot = self.cursor_snapshot.clone(); let tokens = std::iter::once(self.start_token.clone()) - .chain((0..self.num_calls).map(|_| { + .chain((0..num_calls).map(|_| { if self.desugar_doc_comments { cursor_snapshot.next_desugared() } else { cursor_snapshot.next() } })) - .take(self.num_calls); + .take(num_calls); make_token_stream(tokens) } + fn add_trailing_semi(&self) -> Box<dyn CreateTokenStream> { + if self.trailing_semi { + panic!("Called `add_trailing_semi` twice!"); + } + let mut new = self.clone(); + new.trailing_semi = true; + Box::new(new) + } } let lazy_impl = LazyTokenStreamImpl { @@ -1246,6 +1261,7 @@ impl<'a> Parser<'a> { num_calls: self.token_cursor.num_next_calls - cursor_snapshot.num_next_calls, cursor_snapshot, desugar_doc_comments: self.desugar_doc_comments, + trailing_semi: false, }; Ok((ret, Some(LazyTokenStream::new(lazy_impl)))) } diff --git a/compiler/rustc_parse/src/parser/nonterminal.rs b/compiler/rustc_parse/src/parser/nonterminal.rs index ab88362dad9..c007f96a798 100644 --- a/compiler/rustc_parse/src/parser/nonterminal.rs +++ b/compiler/rustc_parse/src/parser/nonterminal.rs @@ -117,8 +117,8 @@ impl<'a> Parser<'a> { let (stmt, tokens) = self.collect_tokens(|this| this.parse_stmt())?; match stmt { Some(mut s) => { - if s.tokens.is_none() { - s.tokens = tokens; + if s.tokens().is_none() { + s.set_tokens(tokens); } token::NtStmt(s) } diff --git a/compiler/rustc_parse/src/parser/path.rs b/compiler/rustc_parse/src/parser/path.rs index d64fd59b0a6..17e5bcf7605 100644 --- a/compiler/rustc_parse/src/parser/path.rs +++ b/compiler/rustc_parse/src/parser/path.rs @@ -3,10 +3,9 @@ use super::{Parser, TokenType}; use crate::maybe_whole; use rustc_ast::ptr::P; use rustc_ast::token::{self, Token}; -use rustc_ast::{ - self as ast, AngleBracketedArg, AngleBracketedArgs, GenericArg, ParenthesizedArgs, -}; +use rustc_ast::{self as ast, AngleBracketedArg, AngleBracketedArgs, ParenthesizedArgs}; use rustc_ast::{AnonConst, AssocTyConstraint, AssocTyConstraintKind, BlockCheckMode}; +use rustc_ast::{GenericArg, GenericArgs}; use rustc_ast::{Path, PathSegment, QSelf}; use rustc_errors::{pluralize, Applicability, PResult}; use rustc_span::source_map::{BytePos, Span}; @@ -414,32 +413,40 @@ impl<'a> Parser<'a> { /// Parses a single argument in the angle arguments `<...>` of a path segment. fn parse_angle_arg(&mut self) -> PResult<'a, Option<AngleBracketedArg>> { - if self.check_ident() && self.look_ahead(1, |t| matches!(t.kind, token::Eq | token::Colon)) - { - // Parse associated type constraint. - let lo = self.token.span; - let ident = self.parse_ident()?; - let kind = if self.eat(&token::Eq) { - let ty = self.parse_assoc_equality_term(ident, self.prev_token.span)?; - AssocTyConstraintKind::Equality { ty } - } else if self.eat(&token::Colon) { - let bounds = self.parse_generic_bounds(Some(self.prev_token.span))?; - AssocTyConstraintKind::Bound { bounds } - } else { - unreachable!(); - }; + let lo = self.token.span; + let arg = self.parse_generic_arg()?; + match arg { + Some(arg) => { + if self.check(&token::Colon) | self.check(&token::Eq) { + let (ident, gen_args) = self.get_ident_from_generic_arg(arg, lo)?; + let kind = if self.eat(&token::Colon) { + // Parse associated type constraint bound. + + let bounds = self.parse_generic_bounds(Some(self.prev_token.span))?; + AssocTyConstraintKind::Bound { bounds } + } else if self.eat(&token::Eq) { + // Parse associated type equality constraint + + let ty = self.parse_assoc_equality_term(ident, self.prev_token.span)?; + AssocTyConstraintKind::Equality { ty } + } else { + unreachable!(); + }; - let span = lo.to(self.prev_token.span); + let span = lo.to(self.prev_token.span); - // Gate associated type bounds, e.g., `Iterator<Item: Ord>`. - if let AssocTyConstraintKind::Bound { .. } = kind { - self.sess.gated_spans.gate(sym::associated_type_bounds, span); + // Gate associated type bounds, e.g., `Iterator<Item: Ord>`. + if let AssocTyConstraintKind::Bound { .. } = kind { + self.sess.gated_spans.gate(sym::associated_type_bounds, span); + } + let constraint = + AssocTyConstraint { id: ast::DUMMY_NODE_ID, ident, gen_args, kind, span }; + Ok(Some(AngleBracketedArg::Constraint(constraint))) + } else { + Ok(Some(AngleBracketedArg::Arg(arg))) + } } - - let constraint = AssocTyConstraint { id: ast::DUMMY_NODE_ID, ident, kind, span }; - Ok(Some(AngleBracketedArg::Constraint(constraint))) - } else { - Ok(self.parse_generic_arg()?.map(AngleBracketedArg::Arg)) + _ => Ok(None), } } @@ -542,4 +549,54 @@ impl<'a> Parser<'a> { }; Ok(Some(arg)) } + + fn get_ident_from_generic_arg( + &self, + gen_arg: GenericArg, + lo: Span, + ) -> PResult<'a, (Ident, Option<GenericArgs>)> { + let gen_arg_span = gen_arg.span(); + match gen_arg { + GenericArg::Type(t) => match t.into_inner().kind { + ast::TyKind::Path(qself, mut path) => { + if let Some(qself) = qself { + let mut err = self.struct_span_err( + gen_arg_span, + "qualified paths cannot be used in associated type constraints", + ); + err.span_label( + qself.path_span, + "not allowed in associated type constraints", + ); + return Err(err); + } + if path.segments.len() == 1 { + let path_seg = path.segments.remove(0); + let ident = path_seg.ident; + let gen_args = path_seg.args.map(|args| args.into_inner()); + return Ok((ident, gen_args)); + } + let err = self.struct_span_err( + path.span, + "paths with multiple segments cannot be used in associated type constraints", + ); + return Err(err); + } + _ => { + let span = lo.to(self.prev_token.span); + let err = self.struct_span_err( + span, + "only path types can be used in associated type constraints", + ); + return Err(err); + } + }, + _ => { + let span = lo.to(self.prev_token.span); + let err = self + .struct_span_err(span, "only types can be used in associated type constraints"); + return Err(err); + } + } + } } diff --git a/compiler/rustc_parse/src/parser/stmt.rs b/compiler/rustc_parse/src/parser/stmt.rs index 131ff1ae6b3..e974556f43a 100644 --- a/compiler/rustc_parse/src/parser/stmt.rs +++ b/compiler/rustc_parse/src/parser/stmt.rs @@ -7,8 +7,10 @@ use super::{BlockMode, Parser, Restrictions, SemiColonMode}; use crate::maybe_whole; use rustc_ast as ast; +use rustc_ast::attr::HasAttrs; use rustc_ast::ptr::P; use rustc_ast::token::{self, TokenKind}; +use rustc_ast::tokenstream::LazyTokenStream; use rustc_ast::util::classify; use rustc_ast::{AttrStyle, AttrVec, Attribute, MacCall, MacCallStmt, MacStmtStyle}; use rustc_ast::{Block, BlockCheckMode, Expr, ExprKind, Local, Stmt, StmtKind, DUMMY_NODE_ID}; @@ -31,45 +33,75 @@ impl<'a> Parser<'a> { } fn parse_stmt_without_recovery(&mut self) -> PResult<'a, Option<Stmt>> { - maybe_whole!(self, NtStmt, |x| Some(x)); - - let attrs = self.parse_outer_attributes()?; + let mut attrs = self.parse_outer_attributes()?; + let has_attrs = !attrs.is_empty(); let lo = self.token.span; - let stmt = if self.eat_keyword(kw::Let) { - self.parse_local_mk(lo, attrs.into())? - } else if self.is_kw_followed_by_ident(kw::Mut) { - self.recover_stmt_local(lo, attrs.into(), "missing keyword", "let mut")? - } else if self.is_kw_followed_by_ident(kw::Auto) { - self.bump(); // `auto` - let msg = "write `let` instead of `auto` to introduce a new variable"; - self.recover_stmt_local(lo, attrs.into(), msg, "let")? - } else if self.is_kw_followed_by_ident(sym::var) { - self.bump(); // `var` - let msg = "write `let` instead of `var` to introduce a new variable"; - self.recover_stmt_local(lo, attrs.into(), msg, "let")? - } else if self.check_path() && !self.token.is_qpath_start() && !self.is_path_start_item() { - // We have avoided contextual keywords like `union`, items with `crate` visibility, - // or `auto trait` items. We aim to parse an arbitrary path `a::b` but not something - // that starts like a path (1 token), but it fact not a path. - // Also, we avoid stealing syntax from `parse_item_`. - self.parse_stmt_path_start(lo, attrs)? - } else if let Some(item) = self.parse_item_common(attrs.clone(), false, true, |_| true)? { - // FIXME: Bad copy of attrs - self.mk_stmt(lo.to(item.span), StmtKind::Item(P(item))) - } else if self.eat(&token::Semi) { - // Do not attempt to parse an expression if we're done here. - self.error_outer_attrs(&attrs); - self.mk_stmt(lo, StmtKind::Empty) - } else if self.token != token::CloseDelim(token::Brace) { - // Remainder are line-expr stmts. - let e = self.parse_expr_res(Restrictions::STMT_EXPR, Some(attrs.into()))?; - self.mk_stmt(lo.to(e.span), StmtKind::Expr(e)) + maybe_whole!(self, NtStmt, |stmt| { + let mut stmt = stmt; + stmt.visit_attrs(|stmt_attrs| { + mem::swap(stmt_attrs, &mut attrs); + stmt_attrs.extend(attrs); + }); + Some(stmt) + }); + + let parse_stmt_inner = |this: &mut Self| { + let stmt = if this.eat_keyword(kw::Let) { + this.parse_local_mk(lo, attrs.into())? + } else if this.is_kw_followed_by_ident(kw::Mut) { + this.recover_stmt_local(lo, attrs.into(), "missing keyword", "let mut")? + } else if this.is_kw_followed_by_ident(kw::Auto) { + this.bump(); // `auto` + let msg = "write `let` instead of `auto` to introduce a new variable"; + this.recover_stmt_local(lo, attrs.into(), msg, "let")? + } else if this.is_kw_followed_by_ident(sym::var) { + this.bump(); // `var` + let msg = "write `let` instead of `var` to introduce a new variable"; + this.recover_stmt_local(lo, attrs.into(), msg, "let")? + } else if this.check_path() + && !this.token.is_qpath_start() + && !this.is_path_start_item() + { + // We have avoided contextual keywords like `union`, items with `crate` visibility, + // or `auto trait` items. We aim to parse an arbitrary path `a::b` but not something + // that starts like a path (1 token), but it fact not a path. + // Also, we avoid stealing syntax from `parse_item_`. + this.parse_stmt_path_start(lo, attrs)? + } else if let Some(item) = + this.parse_item_common(attrs.clone(), false, true, |_| true)? + { + // FIXME: Bad copy of attrs + this.mk_stmt(lo.to(item.span), StmtKind::Item(P(item))) + } else if this.eat(&token::Semi) { + // Do not attempt to parse an expression if we're done here. + this.error_outer_attrs(&attrs); + this.mk_stmt(lo, StmtKind::Empty) + } else if this.token != token::CloseDelim(token::Brace) { + // Remainder are line-expr stmts. + let e = this.parse_expr_res(Restrictions::STMT_EXPR, Some(attrs.into()))?; + this.mk_stmt(lo.to(e.span), StmtKind::Expr(e)) + } else { + this.error_outer_attrs(&attrs); + return Ok(None); + }; + Ok(Some(stmt)) + }; + + let stmt = if has_attrs { + let (mut stmt, tokens) = self.collect_tokens(parse_stmt_inner)?; + if let Some(stmt) = &mut stmt { + // If we already have tokens (e.g. due to encounting an `NtStmt`), + // use those instead. + if stmt.tokens().is_none() { + stmt.set_tokens(tokens); + } + } + stmt } else { - self.error_outer_attrs(&attrs); - return Ok(None); + parse_stmt_inner(self)? }; - Ok(Some(stmt)) + Ok(stmt) } fn parse_stmt_path_start(&mut self, lo: Span, attrs: Vec<Attribute>) -> PResult<'a, Stmt> { @@ -107,7 +139,7 @@ impl<'a> Parser<'a> { let kind = if delim == token::Brace || self.token == token::Semi || self.token == token::Eof { - StmtKind::MacCall(P(MacCallStmt { mac, style, attrs })) + StmtKind::MacCall(P(MacCallStmt { mac, style, attrs, tokens: None })) } else { // Since none of the above applied, this is an expression statement macro. let e = self.mk_expr(lo.to(hi), ExprKind::MacCall(mac), AttrVec::new()); @@ -219,7 +251,7 @@ impl<'a> Parser<'a> { } }; let hi = if self.token == token::Semi { self.token.span } else { self.prev_token.span }; - Ok(P(ast::Local { ty, pat, init, id: DUMMY_NODE_ID, span: lo.to(hi), attrs })) + Ok(P(ast::Local { ty, pat, init, id: DUMMY_NODE_ID, span: lo.to(hi), attrs, tokens: None })) } /// Parses the RHS of a local variable declaration (e.g., '= 14;'). @@ -376,6 +408,12 @@ impl<'a> Parser<'a> { None => return Ok(None), }; + let add_semi_token = |tokens: Option<&mut LazyTokenStream>| { + if let Some(tokens) = tokens { + *tokens = tokens.add_trailing_semi(); + } + }; + let mut eat_semi = true; match stmt.kind { // Expression without semicolon. @@ -417,6 +455,7 @@ impl<'a> Parser<'a> { *expr = self.mk_expr_err(sp); } } + StmtKind::Expr(_) | StmtKind::MacCall(_) => {} StmtKind::Local(ref mut local) => { if let Err(e) = self.expect_semi() { // We might be at the `,` in `let x = foo<bar, baz>;`. Try to recover. @@ -430,13 +469,18 @@ impl<'a> Parser<'a> { } } eat_semi = false; + // We just checked that there's a semicolon in the tokenstream, + // so capture it + add_semi_token(local.tokens.as_mut()); } - StmtKind::Empty => eat_semi = false, - _ => {} + StmtKind::Empty | StmtKind::Item(_) | StmtKind::Semi(_) => eat_semi = false, } if eat_semi && self.eat(&token::Semi) { stmt = stmt.add_trailing_semicolon(); + // We just checked that we have a semicolon in the tokenstream, + // so capture it + add_semi_token(stmt.tokens_mut()); } stmt.span = stmt.span.to(self.prev_token.span); Ok(Some(stmt)) @@ -447,7 +491,7 @@ impl<'a> Parser<'a> { } pub(super) fn mk_stmt(&self, span: Span, kind: StmtKind) -> Stmt { - Stmt { id: DUMMY_NODE_ID, kind, span, tokens: None } + Stmt { id: DUMMY_NODE_ID, kind, span } } pub(super) fn mk_stmt_err(&self, span: Span) -> Stmt { diff --git a/compiler/rustc_passes/src/check_attr.rs b/compiler/rustc_passes/src/check_attr.rs index 7679582f881..9c0234953bb 100644 --- a/compiler/rustc_passes/src/check_attr.rs +++ b/compiler/rustc_passes/src/check_attr.rs @@ -89,6 +89,8 @@ impl CheckAttrVisitor<'tcx> { self.check_allow_internal_unstable(&attr, span, target, &attrs) } else if self.tcx.sess.check_name(attr, sym::rustc_allow_const_fn_unstable) { self.check_rustc_allow_const_fn_unstable(hir_id, &attr, span, target) + } else if self.tcx.sess.check_name(attr, sym::naked) { + self.check_naked(attr, span, target) } else { // lint-only checks if self.tcx.sess.check_name(attr, sym::cold) { @@ -162,6 +164,25 @@ impl CheckAttrVisitor<'tcx> { } } + /// Checks if `#[naked]` is applied to a function definition. + fn check_naked(&self, attr: &Attribute, span: &Span, target: Target) -> bool { + match target { + Target::Fn + | Target::Method(MethodKind::Trait { body: true } | MethodKind::Inherent) => true, + _ => { + self.tcx + .sess + .struct_span_err( + attr.span, + "attribute should be applied to a function definition", + ) + .span_label(*span, "not a function definition") + .emit(); + false + } + } + } + /// Checks if a `#[track_caller]` is applied to a non-naked function. Returns `true` if valid. fn check_track_caller( &self, @@ -171,7 +192,7 @@ impl CheckAttrVisitor<'tcx> { target: Target, ) -> bool { match target { - _ if self.tcx.sess.contains_name(attrs, sym::naked) => { + _ if attrs.iter().any(|attr| attr.has_name(sym::naked)) => { struct_span_err!( self.tcx.sess, *attr_span, diff --git a/compiler/rustc_passes/src/dead.rs b/compiler/rustc_passes/src/dead.rs index f567dd83bc1..b87b13cff80 100644 --- a/compiler/rustc_passes/src/dead.rs +++ b/compiler/rustc_passes/src/dead.rs @@ -190,7 +190,7 @@ impl<'tcx> MarkSymbolVisitor<'tcx> { intravisit::walk_item(self, &item); } - hir::ItemKind::ForeignMod(..) => {} + hir::ItemKind::ForeignMod { .. } => {} _ => { intravisit::walk_item(self, &item); } @@ -447,6 +447,8 @@ impl<'v, 'k, 'tcx> ItemLikeVisitor<'v> for LifeSeeder<'k, 'tcx> { fn visit_impl_item(&mut self, _item: &hir::ImplItem<'_>) { // ignore: we are handling this in `visit_item` above } + + fn visit_foreign_item(&mut self, _item: &'v hir::ForeignItem<'v>) {} } fn create_and_seed_worklist<'tcx>( diff --git a/compiler/rustc_passes/src/diagnostic_items.rs b/compiler/rustc_passes/src/diagnostic_items.rs index 5a087c41f58..699c96bc49d 100644 --- a/compiler/rustc_passes/src/diagnostic_items.rs +++ b/compiler/rustc_passes/src/diagnostic_items.rs @@ -37,6 +37,10 @@ impl<'v, 'tcx> ItemLikeVisitor<'v> for DiagnosticItemCollector<'tcx> { fn visit_impl_item(&mut self, impl_item: &hir::ImplItem<'_>) { self.observe_item(&impl_item.attrs, impl_item.hir_id); } + + fn visit_foreign_item(&mut self, foreign_item: &hir::ForeignItem<'_>) { + self.observe_item(foreign_item.attrs, foreign_item.hir_id); + } } impl<'tcx> DiagnosticItemCollector<'tcx> { @@ -100,18 +104,6 @@ fn collect<'tcx>(tcx: TyCtxt<'tcx>) -> FxHashMap<Symbol, DefId> { // Collect diagnostic items in this crate. tcx.hir().krate().visit_all_item_likes(&mut collector); - // FIXME(visit_all_item_likes): Foreign items are not visited - // here, so we have to manually look at them for now. - for (_, foreign_module) in tcx.foreign_modules(LOCAL_CRATE).iter() { - for &foreign_item in foreign_module.foreign_items.iter() { - match tcx.hir().get(tcx.hir().local_def_id_to_hir_id(foreign_item.expect_local())) { - hir::Node::ForeignItem(item) => { - collector.observe_item(item.attrs, item.hir_id); - } - item => bug!("unexpected foreign item {:?}", item), - } - } - } for m in tcx.hir().krate().exported_macros { collector.observe_item(m.attrs, m.hir_id); diff --git a/compiler/rustc_passes/src/entry.rs b/compiler/rustc_passes/src/entry.rs index e87adb378e7..5ff631a2457 100644 --- a/compiler/rustc_passes/src/entry.rs +++ b/compiler/rustc_passes/src/entry.rs @@ -2,7 +2,7 @@ use rustc_ast::entry::EntryPointType; use rustc_errors::struct_span_err; use rustc_hir::def_id::{CrateNum, LocalDefId, CRATE_DEF_INDEX, LOCAL_CRATE}; use rustc_hir::itemlikevisit::ItemLikeVisitor; -use rustc_hir::{HirId, ImplItem, Item, ItemKind, TraitItem}; +use rustc_hir::{ForeignItem, HirId, ImplItem, Item, ItemKind, TraitItem}; use rustc_middle::hir::map::Map; use rustc_middle::ty::query::Providers; use rustc_middle::ty::TyCtxt; @@ -45,6 +45,10 @@ impl<'a, 'tcx> ItemLikeVisitor<'tcx> for EntryContext<'a, 'tcx> { fn visit_impl_item(&mut self, _impl_item: &'tcx ImplItem<'tcx>) { // Entry fn is never a trait item. } + + fn visit_foreign_item(&mut self, _: &'tcx ForeignItem<'tcx>) { + // Entry fn is never a foreign item. + } } fn entry_fn(tcx: TyCtxt<'_>, cnum: CrateNum) -> Option<(LocalDefId, EntryFnType)> { diff --git a/compiler/rustc_passes/src/hir_id_validator.rs b/compiler/rustc_passes/src/hir_id_validator.rs index 6d1a5fcc10b..c7e057927ab 100644 --- a/compiler/rustc_passes/src/hir_id_validator.rs +++ b/compiler/rustc_passes/src/hir_id_validator.rs @@ -68,6 +68,11 @@ impl<'a, 'hir> ItemLikeVisitor<'hir> for OuterVisitor<'a, 'hir> { let mut inner_visitor = self.new_inner_visitor(self.hir_map); inner_visitor.check(i.hir_id, |this| intravisit::walk_impl_item(this, i)); } + + fn visit_foreign_item(&mut self, i: &'hir hir::ForeignItem<'hir>) { + let mut inner_visitor = self.new_inner_visitor(self.hir_map); + inner_visitor.check(i.hir_id, |this| intravisit::walk_foreign_item(this, i)); + } } impl<'a, 'hir> HirIdValidator<'a, 'hir> { diff --git a/compiler/rustc_passes/src/lang_items.rs b/compiler/rustc_passes/src/lang_items.rs index 0ae0c381a11..3132661e5f5 100644 --- a/compiler/rustc_passes/src/lang_items.rs +++ b/compiler/rustc_passes/src/lang_items.rs @@ -54,6 +54,8 @@ impl ItemLikeVisitor<'v> for LanguageItemCollector<'tcx> { impl_item.attrs, ) } + + fn visit_foreign_item(&mut self, _: &hir::ForeignItem<'_>) {} } impl LanguageItemCollector<'tcx> { diff --git a/compiler/rustc_passes/src/layout_test.rs b/compiler/rustc_passes/src/layout_test.rs index 504cbbfcb76..9e83cbd6680 100644 --- a/compiler/rustc_passes/src/layout_test.rs +++ b/compiler/rustc_passes/src/layout_test.rs @@ -40,6 +40,7 @@ impl ItemLikeVisitor<'tcx> for LayoutTest<'tcx> { fn visit_trait_item(&mut self, _: &'tcx hir::TraitItem<'tcx>) {} fn visit_impl_item(&mut self, _: &'tcx hir::ImplItem<'tcx>) {} + fn visit_foreign_item(&mut self, _: &'tcx hir::ForeignItem<'tcx>) {} } impl LayoutTest<'tcx> { diff --git a/compiler/rustc_passes/src/lib.rs b/compiler/rustc_passes/src/lib.rs index c32c9c8eaa6..9759a500e06 100644 --- a/compiler/rustc_passes/src/lib.rs +++ b/compiler/rustc_passes/src/lib.rs @@ -7,6 +7,7 @@ #![doc(html_root_url = "https://doc.rust-lang.org/nightly/nightly-rustc/")] #![feature(const_fn)] #![feature(const_panic)] +#![feature(crate_visibility_modifier)] #![feature(in_band_lifetimes)] #![feature(nll)] #![feature(or_patterns)] @@ -32,6 +33,7 @@ pub mod layout_test; mod lib_features; mod liveness; pub mod loops; +mod naked_functions; mod reachable; mod region; pub mod stability; @@ -46,6 +48,7 @@ pub fn provide(providers: &mut Providers) { lang_items::provide(providers); lib_features::provide(providers); loops::provide(providers); + naked_functions::provide(providers); liveness::provide(providers); intrinsicck::provide(providers); reachable::provide(providers); diff --git a/compiler/rustc_passes/src/naked_functions.rs b/compiler/rustc_passes/src/naked_functions.rs new file mode 100644 index 00000000000..6ef45cdd391 --- /dev/null +++ b/compiler/rustc_passes/src/naked_functions.rs @@ -0,0 +1,113 @@ +use rustc_hir as hir; +use rustc_hir::def_id::LocalDefId; +use rustc_hir::intravisit::{ErasedMap, FnKind, NestedVisitorMap, Visitor}; +use rustc_middle::ty::query::Providers; +use rustc_middle::ty::TyCtxt; +use rustc_span::symbol::sym; +use rustc_span::Span; + +fn check_mod_naked_functions(tcx: TyCtxt<'_>, module_def_id: LocalDefId) { + tcx.hir().visit_item_likes_in_module( + module_def_id, + &mut CheckNakedFunctions { tcx }.as_deep_visitor(), + ); +} + +crate fn provide(providers: &mut Providers) { + *providers = Providers { check_mod_naked_functions, ..*providers }; +} + +struct CheckNakedFunctions<'tcx> { + tcx: TyCtxt<'tcx>, +} + +impl<'tcx> Visitor<'tcx> for CheckNakedFunctions<'tcx> { + type Map = ErasedMap<'tcx>; + + fn nested_visit_map(&mut self) -> NestedVisitorMap<Self::Map> { + NestedVisitorMap::None + } + + fn visit_fn( + &mut self, + fk: FnKind<'v>, + _fd: &'tcx hir::FnDecl<'tcx>, + body_id: hir::BodyId, + _span: Span, + _hir_id: hir::HirId, + ) { + match fk { + // Rejected during attribute check. Do not validate further. + FnKind::Closure(..) => return, + FnKind::ItemFn(..) | FnKind::Method(..) => {} + } + + let naked = fk.attrs().iter().any(|attr| attr.has_name(sym::naked)); + if naked { + let body = self.tcx.hir().body(body_id); + check_params(self.tcx, body); + check_body(self.tcx, body); + } + } +} + +/// Checks that parameters don't use patterns. Mirrors the checks for function declarations. +fn check_params(tcx: TyCtxt<'_>, body: &hir::Body<'_>) { + for param in body.params { + match param.pat.kind { + hir::PatKind::Wild + | hir::PatKind::Binding(hir::BindingAnnotation::Unannotated, _, _, None) => {} + _ => { + tcx.sess + .struct_span_err( + param.pat.span, + "patterns not allowed in naked function parameters", + ) + .emit(); + } + } + } +} + +/// Checks that function parameters aren't referenced in the function body. +fn check_body<'tcx>(tcx: TyCtxt<'tcx>, body: &'tcx hir::Body<'tcx>) { + let mut params = hir::HirIdSet::default(); + for param in body.params { + param.pat.each_binding(|_binding_mode, hir_id, _span, _ident| { + params.insert(hir_id); + }); + } + CheckBody { tcx, params }.visit_body(body); +} + +struct CheckBody<'tcx> { + tcx: TyCtxt<'tcx>, + params: hir::HirIdSet, +} + +impl<'tcx> Visitor<'tcx> for CheckBody<'tcx> { + type Map = ErasedMap<'tcx>; + + fn nested_visit_map(&mut self) -> NestedVisitorMap<Self::Map> { + NestedVisitorMap::None + } + + fn visit_expr(&mut self, expr: &'tcx hir::Expr<'tcx>) { + if let hir::ExprKind::Path(hir::QPath::Resolved( + _, + hir::Path { res: hir::def::Res::Local(var_hir_id), .. }, + )) = expr.kind + { + if self.params.contains(var_hir_id) { + self.tcx + .sess + .struct_span_err( + expr.span, + "use of parameters not allowed inside naked functions", + ) + .emit(); + } + } + hir::intravisit::walk_expr(self, expr); + } +} diff --git a/compiler/rustc_passes/src/reachable.rs b/compiler/rustc_passes/src/reachable.rs index 8d5c980609c..fde83af99a5 100644 --- a/compiler/rustc_passes/src/reachable.rs +++ b/compiler/rustc_passes/src/reachable.rs @@ -262,7 +262,7 @@ impl<'tcx> ReachableContext<'tcx> { | hir::ItemKind::TyAlias(..) | hir::ItemKind::Static(..) | hir::ItemKind::Mod(..) - | hir::ItemKind::ForeignMod(..) + | hir::ItemKind::ForeignMod { .. } | hir::ItemKind::Impl { .. } | hir::ItemKind::Trait(..) | hir::ItemKind::TraitAlias(..) @@ -378,6 +378,10 @@ impl<'a, 'tcx> ItemLikeVisitor<'tcx> for CollectPrivateImplItemsVisitor<'a, 'tcx fn visit_impl_item(&mut self, _impl_item: &hir::ImplItem<'_>) { // processed in visit_item above } + + fn visit_foreign_item(&mut self, _foreign_item: &hir::ForeignItem<'_>) { + // We never export foreign functions as they have no body to export. + } } fn reachable_set<'tcx>(tcx: TyCtxt<'tcx>, crate_num: CrateNum) -> FxHashSet<LocalDefId> { diff --git a/compiler/rustc_passes/src/stability.rs b/compiler/rustc_passes/src/stability.rs index 04b5c65e464..f6bbbd80bf1 100644 --- a/compiler/rustc_passes/src/stability.rs +++ b/compiler/rustc_passes/src/stability.rs @@ -326,7 +326,7 @@ impl<'a, 'tcx> Visitor<'tcx> for Annotator<'a, 'tcx> { // 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::ItemKind::Impl { of_trait: None, .. } | hir::ItemKind::ForeignMod(..) => { + hir::ItemKind::Impl { of_trait: None, .. } | hir::ItemKind::ForeignMod { .. } => { self.in_trait_impl = false; kind = AnnotationKind::Container; } @@ -499,7 +499,7 @@ impl<'tcx> Visitor<'tcx> for MissingStabilityAnnotations<'tcx> { // optional. They inherit stability from their parents when unannotated. if !matches!( i.kind, - hir::ItemKind::Impl { of_trait: None, .. } | hir::ItemKind::ForeignMod(..) + hir::ItemKind::Impl { of_trait: None, .. } | hir::ItemKind::ForeignMod { .. } ) { self.check_missing_stability(i.hir_id, i.span); } diff --git a/compiler/rustc_plugin_impl/src/build.rs b/compiler/rustc_plugin_impl/src/build.rs index d16dd701a12..4796d9a80b6 100644 --- a/compiler/rustc_plugin_impl/src/build.rs +++ b/compiler/rustc_plugin_impl/src/build.rs @@ -25,6 +25,8 @@ impl<'v, 'tcx> ItemLikeVisitor<'v> for RegistrarFinder<'tcx> { fn visit_trait_item(&mut self, _trait_item: &hir::TraitItem<'_>) {} fn visit_impl_item(&mut self, _impl_item: &hir::ImplItem<'_>) {} + + fn visit_foreign_item(&mut self, _foreign_item: &hir::ForeignItem<'_>) {} } /// Finds the function marked with `#[plugin_registrar]`, if any. diff --git a/compiler/rustc_privacy/src/lib.rs b/compiler/rustc_privacy/src/lib.rs index b8fa9081aa3..4414bf57c6b 100644 --- a/compiler/rustc_privacy/src/lib.rs +++ b/compiler/rustc_privacy/src/lib.rs @@ -592,7 +592,7 @@ impl Visitor<'tcx> for EmbargoVisitor<'tcx> { Option::<AccessLevel>::of_impl(item.hir_id, self.tcx, &self.access_levels) } // Foreign modules inherit level from parents. - hir::ItemKind::ForeignMod(..) => self.prev_level, + hir::ItemKind::ForeignMod { .. } => self.prev_level, // Other `pub` items inherit levels from parents. hir::ItemKind::Const(..) | hir::ItemKind::Enum(..) @@ -654,10 +654,10 @@ impl Visitor<'tcx> for EmbargoVisitor<'tcx> { } } } - hir::ItemKind::ForeignMod(ref foreign_mod) => { - for foreign_item in foreign_mod.items { + hir::ItemKind::ForeignMod { items, .. } => { + for foreign_item in items { if foreign_item.vis.node.is_pub() { - self.update(foreign_item.hir_id, item_level); + self.update(foreign_item.id.hir_id, item_level); } } } @@ -770,11 +770,11 @@ impl Visitor<'tcx> for EmbargoVisitor<'tcx> { } } // Visit everything, but foreign items have their own levels. - hir::ItemKind::ForeignMod(ref foreign_mod) => { - for foreign_item in foreign_mod.items { - let foreign_item_level = self.get(foreign_item.hir_id); + hir::ItemKind::ForeignMod { items, .. } => { + for foreign_item in items { + let foreign_item_level = self.get(foreign_item.id.hir_id); if foreign_item_level.is_some() { - self.reach(foreign_item.hir_id, foreign_item_level) + self.reach(foreign_item.id.hir_id, foreign_item_level) .generics() .predicates() .ty(); @@ -1430,7 +1430,7 @@ impl<'a, 'tcx> Visitor<'tcx> for ObsoleteVisiblePrivateTypesVisitor<'a, 'tcx> { // An `extern {}` doesn't introduce a new privacy // namespace (the contents have their own privacies). - hir::ItemKind::ForeignMod(_) => {} + hir::ItemKind::ForeignMod { .. } => {} hir::ItemKind::Trait(.., ref bounds, _) => { if !self.trait_is_public(item.hir_id) { @@ -1948,10 +1948,10 @@ impl<'a, 'tcx> Visitor<'tcx> for PrivateItemsInPublicInterfacesVisitor<'a, 'tcx> } } // Subitems of foreign modules have their own publicity. - hir::ItemKind::ForeignMod(ref foreign_mod) => { - for foreign_item in foreign_mod.items { - let vis = tcx.visibility(tcx.hir().local_def_id(foreign_item.hir_id)); - self.check(foreign_item.hir_id, vis).generics().predicates().ty(); + hir::ItemKind::ForeignMod { items, .. } => { + for foreign_item in items { + let vis = tcx.visibility(tcx.hir().local_def_id(foreign_item.id.hir_id)); + self.check(foreign_item.id.hir_id, vis).generics().predicates().ty(); } } // Subitems of structs and unions have their own publicity. diff --git a/compiler/rustc_resolve/src/diagnostics.rs b/compiler/rustc_resolve/src/diagnostics.rs index a0d5b61e8bd..809de9beff6 100644 --- a/compiler/rustc_resolve/src/diagnostics.rs +++ b/compiler/rustc_resolve/src/diagnostics.rs @@ -1,7 +1,6 @@ use std::cmp::Reverse; use std::ptr; -use rustc_ast::util::lev_distance::find_best_match_for_name; use rustc_ast::{self as ast, Path}; use rustc_ast_pretty::pprust; use rustc_data_structures::fx::FxHashSet; @@ -14,6 +13,7 @@ use rustc_middle::bug; use rustc_middle::ty::{self, DefIdTree}; use rustc_session::Session; use rustc_span::hygiene::MacroKind; +use rustc_span::lev_distance::find_best_match_for_name; use rustc_span::source_map::SourceMap; use rustc_span::symbol::{kw, sym, Ident, Symbol}; use rustc_span::{BytePos, MultiSpan, Span}; @@ -716,7 +716,7 @@ impl<'a> Resolver<'a> { suggestions.sort_by_cached_key(|suggestion| suggestion.candidate.as_str()); match find_best_match_for_name( - suggestions.iter().map(|suggestion| &suggestion.candidate), + &suggestions.iter().map(|suggestion| suggestion.candidate).collect::<Vec<Symbol>>(), ident.name, None, ) { diff --git a/compiler/rustc_resolve/src/imports.rs b/compiler/rustc_resolve/src/imports.rs index 026cf8be738..cb1f0834ce7 100644 --- a/compiler/rustc_resolve/src/imports.rs +++ b/compiler/rustc_resolve/src/imports.rs @@ -10,7 +10,6 @@ use crate::{CrateLint, Module, ModuleOrUniformRoot, ParentScope, PerNS, ScopeSet use crate::{NameBinding, NameBindingKind, PathResult, PrivacyError, ToNameBinding}; use rustc_ast::unwrap_or; -use rustc_ast::util::lev_distance::find_best_match_for_name; use rustc_ast::NodeId; use rustc_ast_lowering::ResolverAstLowering; use rustc_data_structures::fx::FxHashSet; @@ -25,6 +24,7 @@ use rustc_session::lint::builtin::{PUB_USE_OF_PRIVATE_EXTERN_CRATE, UNUSED_IMPOR use rustc_session::lint::BuiltinLintDiagnostics; use rustc_session::DiagnosticMessageId; use rustc_span::hygiene::ExpnId; +use rustc_span::lev_distance::find_best_match_for_name; use rustc_span::symbol::{kw, Ident, Symbol}; use rustc_span::{MultiSpan, Span}; @@ -1096,33 +1096,37 @@ impl<'a, 'b> ImportResolver<'a, 'b> { _ => None, }; let resolutions = resolutions.as_ref().into_iter().flat_map(|r| r.iter()); - let names = resolutions.filter_map(|(BindingKey { ident: i, .. }, resolution)| { - if *i == ident { - return None; - } // Never suggest the same name - match *resolution.borrow() { - NameResolution { binding: Some(name_binding), .. } => { - match name_binding.kind { - NameBindingKind::Import { binding, .. } => { - match binding.kind { - // Never suggest the name that has binding error - // i.e., the name that cannot be previously resolved - NameBindingKind::Res(Res::Err, _) => None, - _ => Some(&i.name), + let names = resolutions + .filter_map(|(BindingKey { ident: i, .. }, resolution)| { + if *i == ident { + return None; + } // Never suggest the same name + match *resolution.borrow() { + NameResolution { binding: Some(name_binding), .. } => { + match name_binding.kind { + NameBindingKind::Import { binding, .. } => { + match binding.kind { + // Never suggest the name that has binding error + // i.e., the name that cannot be previously resolved + NameBindingKind::Res(Res::Err, _) => None, + _ => Some(i.name), + } } + _ => Some(i.name), } - _ => Some(&i.name), } + NameResolution { ref single_imports, .. } + if single_imports.is_empty() => + { + None + } + _ => Some(i.name), } - NameResolution { ref single_imports, .. } if single_imports.is_empty() => { - None - } - _ => Some(&i.name), - } - }); + }) + .collect::<Vec<Symbol>>(); let lev_suggestion = - find_best_match_for_name(names, ident.name, None).map(|suggestion| { + find_best_match_for_name(&names, ident.name, None).map(|suggestion| { ( vec![(ident.span, suggestion.to_string())], String::from("a similar name exists in the module"), diff --git a/compiler/rustc_resolve/src/late/diagnostics.rs b/compiler/rustc_resolve/src/late/diagnostics.rs index 2473436a916..6ce299a9417 100644 --- a/compiler/rustc_resolve/src/late/diagnostics.rs +++ b/compiler/rustc_resolve/src/late/diagnostics.rs @@ -5,7 +5,6 @@ use crate::path_names_to_string; use crate::{CrateLint, Module, ModuleKind, ModuleOrUniformRoot}; use crate::{PathResult, PathSource, Segment}; -use rustc_ast::util::lev_distance::find_best_match_for_name; use rustc_ast::visit::FnKind; use rustc_ast::{self as ast, Expr, ExprKind, Item, ItemKind, NodeId, Path, Ty, TyKind}; use rustc_ast_pretty::pprust::path_segment_to_string; @@ -18,6 +17,7 @@ use rustc_hir::def_id::{DefId, CRATE_DEF_INDEX, LOCAL_CRATE}; use rustc_hir::PrimTy; use rustc_session::parse::feature_err; use rustc_span::hygiene::MacroKind; +use rustc_span::lev_distance::find_best_match_for_name; use rustc_span::symbol::{kw, sym, Ident, Symbol}; use rustc_span::{BytePos, MultiSpan, Span, DUMMY_SP}; @@ -1206,7 +1206,7 @@ impl<'a: 'ast, 'ast> LateResolutionVisitor<'a, '_, 'ast> { names.sort_by_cached_key(|suggestion| suggestion.candidate.as_str()); match find_best_match_for_name( - names.iter().map(|suggestion| &suggestion.candidate), + &names.iter().map(|suggestion| suggestion.candidate).collect::<Vec<Symbol>>(), name, None, ) { @@ -1592,9 +1592,10 @@ impl<'a: 'ast, 'ast> LateResolutionVisitor<'a, '_, 'ast> { .bindings .iter() .filter(|(id, _)| id.span.ctxt() == label.span.ctxt()) - .map(|(id, _)| &id.name); + .map(|(id, _)| id.name) + .collect::<Vec<Symbol>>(); - find_best_match_for_name(names, label.name, None).map(|symbol| { + find_best_match_for_name(&names, label.name, None).map(|symbol| { // Upon finding a similar name, get the ident that it was from - the span // contained within helps make a useful diagnostic. In addition, determine // whether this candidate is within scope. diff --git a/compiler/rustc_resolve/src/late/lifetimes.rs b/compiler/rustc_resolve/src/late/lifetimes.rs index c79d670737e..91edbebc05f 100644 --- a/compiler/rustc_resolve/src/late/lifetimes.rs +++ b/compiler/rustc_resolve/src/late/lifetimes.rs @@ -388,7 +388,7 @@ impl<'a, 'tcx> Visitor<'tcx> for LifetimeContext<'a, 'tcx> { hir::ItemKind::ExternCrate(_) | hir::ItemKind::Use(..) | hir::ItemKind::Mod(..) - | hir::ItemKind::ForeignMod(..) + | hir::ItemKind::ForeignMod { .. } | hir::ItemKind::GlobalAsm(..) => { // These sorts of items have no lifetime parameters at all. intravisit::walk_item(self, item); diff --git a/compiler/rustc_save_analysis/src/sig.rs b/compiler/rustc_save_analysis/src/sig.rs index 2f82d0546ba..ff445d727fa 100644 --- a/compiler/rustc_save_analysis/src/sig.rs +++ b/compiler/rustc_save_analysis/src/sig.rs @@ -550,7 +550,7 @@ impl<'hir> Sig for hir::Item<'hir> { // FIXME where clause } - hir::ItemKind::ForeignMod(_) => Err("extern mod"), + hir::ItemKind::ForeignMod { .. } => Err("extern mod"), hir::ItemKind::GlobalAsm(_) => Err("global asm"), hir::ItemKind::ExternCrate(_) => Err("extern crate"), hir::ItemKind::OpaqueTy(..) => Err("opaque type"), diff --git a/compiler/rustc_session/src/options.rs b/compiler/rustc_session/src/options.rs index 731bbf029fa..b438be0696a 100644 --- a/compiler/rustc_session/src/options.rs +++ b/compiler/rustc_session/src/options.rs @@ -1008,7 +1008,7 @@ options! {DebuggingOptions, DebuggingSetter, basic_debugging_options, "whether to use the PLT when calling into shared libraries; only has effect for PIC code on systems with ELF binaries (default: PLT is disabled if full relro is enabled)"), - polonius: bool = (false, parse_bool, [UNTRACKED], + polonius: bool = (false, parse_bool, [TRACKED], "enable polonius-based borrow-checker (default: no)"), polymorphize: bool = (false, parse_bool, [TRACKED], "perform polymorphization analysis"), diff --git a/compiler/rustc_ast/src/util/lev_distance.rs b/compiler/rustc_span/src/lev_distance.rs index 21c2c925bc4..edc6625a6ea 100644 --- a/compiler/rustc_ast/src/util/lev_distance.rs +++ b/compiler/rustc_span/src/lev_distance.rs @@ -1,6 +1,4 @@ -// FIXME(Centril): Move to rustc_span? - -use rustc_span::symbol::Symbol; +use crate::symbol::Symbol; use std::cmp; #[cfg(test)] @@ -45,17 +43,14 @@ pub fn lev_distance(a: &str, b: &str) -> usize { /// /// Besides Levenshtein, we use case insensitive comparison to improve accuracy on an edge case with /// a lower(upper)case letters mismatch. -pub fn find_best_match_for_name<'a, T>( - iter_names: T, +#[cold] +pub fn find_best_match_for_name( + name_vec: &[Symbol], lookup: Symbol, dist: Option<usize>, -) -> Option<Symbol> -where - T: Iterator<Item = &'a Symbol>, -{ +) -> Option<Symbol> { let lookup = &lookup.as_str(); let max_dist = dist.unwrap_or_else(|| cmp::max(lookup.len(), 3) / 3); - let name_vec: Vec<&Symbol> = iter_names.collect(); let (case_insensitive_match, levenshtein_match) = name_vec .iter() @@ -83,18 +78,18 @@ where // 2. Levenshtein distance match // 3. Sorted word match if let Some(candidate) = case_insensitive_match { - Some(*candidate) + Some(candidate) } else if levenshtein_match.is_some() { - levenshtein_match.map(|(candidate, _)| *candidate) + levenshtein_match.map(|(candidate, _)| candidate) } else { find_match_by_sorted_words(name_vec, lookup) } } -fn find_match_by_sorted_words<'a>(iter_names: Vec<&'a Symbol>, lookup: &str) -> Option<Symbol> { +fn find_match_by_sorted_words(iter_names: &[Symbol], lookup: &str) -> Option<Symbol> { iter_names.iter().fold(None, |result, candidate| { if sort_by_words(&candidate.as_str()) == sort_by_words(lookup) { - Some(**candidate) + Some(*candidate) } else { result } diff --git a/compiler/rustc_ast/src/util/lev_distance/tests.rs b/compiler/rustc_span/src/lev_distance/tests.rs index 7ebedbcb76a..7aa01cb8efe 100644 --- a/compiler/rustc_ast/src/util/lev_distance/tests.rs +++ b/compiler/rustc_span/src/lev_distance/tests.rs @@ -21,38 +21,35 @@ fn test_lev_distance() { #[test] fn test_find_best_match_for_name() { - use rustc_span::with_default_session_globals; + use crate::with_default_session_globals; with_default_session_globals(|| { let input = vec![Symbol::intern("aaab"), Symbol::intern("aaabc")]; assert_eq!( - find_best_match_for_name(input.iter(), Symbol::intern("aaaa"), None), + find_best_match_for_name(&input, Symbol::intern("aaaa"), None), Some(Symbol::intern("aaab")) ); - assert_eq!( - find_best_match_for_name(input.iter(), Symbol::intern("1111111111"), None), - None - ); + assert_eq!(find_best_match_for_name(&input, Symbol::intern("1111111111"), None), None); let input = vec![Symbol::intern("aAAA")]; assert_eq!( - find_best_match_for_name(input.iter(), Symbol::intern("AAAA"), None), + find_best_match_for_name(&input, Symbol::intern("AAAA"), None), Some(Symbol::intern("aAAA")) ); let input = vec![Symbol::intern("AAAA")]; // Returns None because `lev_distance > max_dist / 3` - assert_eq!(find_best_match_for_name(input.iter(), Symbol::intern("aaaa"), None), None); + assert_eq!(find_best_match_for_name(&input, Symbol::intern("aaaa"), None), None); let input = vec![Symbol::intern("AAAA")]; assert_eq!( - find_best_match_for_name(input.iter(), Symbol::intern("aaaa"), Some(4)), + find_best_match_for_name(&input, Symbol::intern("aaaa"), Some(4)), Some(Symbol::intern("AAAA")) ); let input = vec![Symbol::intern("a_longer_variable_name")]; assert_eq!( - find_best_match_for_name(input.iter(), Symbol::intern("a_variable_longer_name"), None), + find_best_match_for_name(&input, Symbol::intern("a_variable_longer_name"), None), Some(Symbol::intern("a_longer_variable_name")) ); }) diff --git a/compiler/rustc_span/src/lib.rs b/compiler/rustc_span/src/lib.rs index 0926561f4c5..11a49d1ab88 100644 --- a/compiler/rustc_span/src/lib.rs +++ b/compiler/rustc_span/src/lib.rs @@ -34,6 +34,7 @@ use hygiene::Transparency; pub use hygiene::{DesugaringKind, ExpnData, ExpnId, ExpnKind, ForLoopLoc, MacroKind}; pub mod def_id; use def_id::{CrateNum, DefId, LOCAL_CRATE}; +pub mod lev_distance; mod span_encoding; pub use span_encoding::{Span, DUMMY_SP}; diff --git a/compiler/rustc_span/src/symbol.rs b/compiler/rustc_span/src/symbol.rs index 338ff005995..d5fccdeb189 100644 --- a/compiler/rustc_span/src/symbol.rs +++ b/compiler/rustc_span/src/symbol.rs @@ -285,6 +285,7 @@ symbols! { attr_literals, attributes, augmented_assignments, + auto_traits, automatically_derived, avx512_target_feature, await_macro, diff --git a/compiler/rustc_symbol_mangling/src/test.rs b/compiler/rustc_symbol_mangling/src/test.rs index a28c8cac728..8c5e438a728 100644 --- a/compiler/rustc_symbol_mangling/src/test.rs +++ b/compiler/rustc_symbol_mangling/src/test.rs @@ -71,4 +71,8 @@ impl hir::itemlikevisit::ItemLikeVisitor<'tcx> for SymbolNamesTest<'tcx> { fn visit_impl_item(&mut self, impl_item: &'tcx hir::ImplItem<'tcx>) { self.process_attrs(impl_item.hir_id); } + + fn visit_foreign_item(&mut self, foreign_item: &'tcx hir::ForeignItem<'tcx>) { + self.process_attrs(foreign_item.hir_id); + } } diff --git a/compiler/rustc_target/src/spec/aarch64_apple_ios_macabi.rs b/compiler/rustc_target/src/spec/aarch64_apple_ios_macabi.rs new file mode 100644 index 00000000000..3a881975236 --- /dev/null +++ b/compiler/rustc_target/src/spec/aarch64_apple_ios_macabi.rs @@ -0,0 +1,31 @@ +use super::apple_sdk_base::{opts, Arch}; +use crate::spec::{Target, TargetOptions}; + +pub fn target() -> Target { + let base = opts("ios", Arch::Arm64_macabi); + Target { + llvm_target: "arm64-apple-ios-macabi".to_string(), + pointer_width: 64, + data_layout: "e-m:o-i64:64-i128:128-n32:64-S128".to_string(), + arch: "aarch64".to_string(), + options: TargetOptions { + features: "+neon,+fp-armv8,+apple-a7".to_string(), + eliminate_frame_pointer: false, + max_atomic_width: Some(128), + unsupported_abis: super::arm_base::unsupported_abis(), + forces_embed_bitcode: true, + // Taken from a clang build on Xcode 11.4.1. + // These arguments are not actually invoked - they just have + // to look right to pass App Store validation. + bitcode_llvm_cmdline: "-triple\0\ + arm64-apple-ios-macabi\0\ + -emit-obj\0\ + -disable-llvm-passes\0\ + -target-abi\0\ + darwinpcs\0\ + -Os\0" + .to_string(), + ..base + }, + } +} diff --git a/compiler/rustc_target/src/spec/apple_sdk_base.rs b/compiler/rustc_target/src/spec/apple_sdk_base.rs index 092401f1146..d894f759937 100644 --- a/compiler/rustc_target/src/spec/apple_sdk_base.rs +++ b/compiler/rustc_target/src/spec/apple_sdk_base.rs @@ -10,6 +10,7 @@ pub enum Arch { I386, X86_64, X86_64_macabi, + Arm64_macabi, } fn target_cpu(arch: Arch) -> String { @@ -20,6 +21,7 @@ fn target_cpu(arch: Arch) -> String { I386 => "yonah", X86_64 => "core2", X86_64_macabi => "core2", + Arm64_macabi => "apple-a12", } .to_string() } @@ -27,7 +29,7 @@ fn target_cpu(arch: Arch) -> String { fn link_env_remove(arch: Arch) -> Vec<String> { match arch { Armv7 | Armv7s | Arm64 | I386 | X86_64 => vec!["MACOSX_DEPLOYMENT_TARGET".to_string()], - X86_64_macabi => vec!["IPHONEOS_DEPLOYMENT_TARGET".to_string()], + X86_64_macabi | Arm64_macabi => vec!["IPHONEOS_DEPLOYMENT_TARGET".to_string()], } } diff --git a/compiler/rustc_target/src/spec/mod.rs b/compiler/rustc_target/src/spec/mod.rs index 1bda33939b8..b4414e53331 100644 --- a/compiler/rustc_target/src/spec/mod.rs +++ b/compiler/rustc_target/src/spec/mod.rs @@ -579,6 +579,7 @@ supported_targets! { ("armv7-apple-ios", armv7_apple_ios), ("armv7s-apple-ios", armv7s_apple_ios), ("x86_64-apple-ios-macabi", x86_64_apple_ios_macabi), + ("aarch64-apple-ios-macabi", aarch64_apple_ios_macabi), ("aarch64-apple-tvos", aarch64_apple_tvos), ("x86_64-apple-tvos", x86_64_apple_tvos), diff --git a/compiler/rustc_ty_utils/src/ty.rs b/compiler/rustc_ty_utils/src/ty.rs index 720ad42da2a..aa1de6d51cb 100644 --- a/compiler/rustc_ty_utils/src/ty.rs +++ b/compiler/rustc_ty_utils/src/ty.rs @@ -309,7 +309,7 @@ fn well_formed_types_in_env<'tcx>( InherentImpl, Fn, Other, - }; + } let node_kind = match node { Node::TraitItem(item) => match item.kind { diff --git a/compiler/rustc_typeck/src/astconv/errors.rs b/compiler/rustc_typeck/src/astconv/errors.rs index 685243f54cb..b04acd9660d 100644 --- a/compiler/rustc_typeck/src/astconv/errors.rs +++ b/compiler/rustc_typeck/src/astconv/errors.rs @@ -1,11 +1,11 @@ use crate::astconv::AstConv; -use rustc_ast::util::lev_distance::find_best_match_for_name; use rustc_data_structures::fx::FxHashMap; use rustc_errors::{pluralize, struct_span_err, Applicability}; use rustc_hir as hir; use rustc_hir::def_id::DefId; use rustc_middle::ty; use rustc_session::parse::feature_err; +use rustc_span::lev_distance::find_best_match_for_name; use rustc_span::symbol::{sym, Ident}; use rustc_span::{Span, DUMMY_SP}; @@ -180,7 +180,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { .collect(); if let (Some(suggested_name), true) = ( - find_best_match_for_name(all_candidate_names.iter(), assoc_name.name, None), + find_best_match_for_name(&all_candidate_names, assoc_name.name, None), assoc_name.span != DUMMY_SP, ) { err.span_suggestion( diff --git a/compiler/rustc_typeck/src/astconv/mod.rs b/compiler/rustc_typeck/src/astconv/mod.rs index b011e26d64b..2f64597a510 100644 --- a/compiler/rustc_typeck/src/astconv/mod.rs +++ b/compiler/rustc_typeck/src/astconv/mod.rs @@ -13,7 +13,6 @@ use crate::errors::{ }; use crate::middle::resolve_lifetime as rl; use crate::require_c_abi_if_c_variadic; -use rustc_ast::util::lev_distance::find_best_match_for_name; use rustc_data_structures::fx::{FxHashMap, FxHashSet}; use rustc_errors::{struct_span_err, Applicability, ErrorReported, FatalError}; use rustc_hir as hir; @@ -26,6 +25,7 @@ use rustc_middle::ty::subst::{self, InternalSubsts, Subst, SubstsRef}; use rustc_middle::ty::GenericParamDefKind; use rustc_middle::ty::{self, Const, DefIdTree, Ty, TyCtxt, TypeFoldable}; use rustc_session::lint::builtin::AMBIGUOUS_ASSOCIATED_ITEMS; +use rustc_span::lev_distance::find_best_match_for_name; use rustc_span::symbol::{Ident, Symbol}; use rustc_span::{Span, DUMMY_SP}; use rustc_target::spec::abi; @@ -337,6 +337,14 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { infer_args, ); + // Skip processing if type has no generic parameters. + // Traits always have `Self` as a generic parameter, which means they will not return early + // here and so associated type bindings will be handled regardless of whether there are any + // non-`Self` generic parameters. + if generic_params.params.len() == 0 { + return (tcx.intern_substs(&[]), vec![], arg_count); + } + let is_object = self_ty.map_or(false, |ty| ty == self.tcx().types.trait_object_dummy_self); struct SubstsForAstPathCtxt<'a, 'tcx> { @@ -1579,7 +1587,11 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o { let adt_def = qself_ty.ty_adt_def().expect("enum is not an ADT"); if let Some(suggested_name) = find_best_match_for_name( - adt_def.variants.iter().map(|variant| &variant.ident.name), + &adt_def + .variants + .iter() + .map(|variant| variant.ident.name) + .collect::<Vec<Symbol>>(), assoc_ident.name, None, ) { diff --git a/compiler/rustc_typeck/src/check/check.rs b/compiler/rustc_typeck/src/check/check.rs index d5518dfc15a..55c815b21ad 100644 --- a/compiler/rustc_typeck/src/check/check.rs +++ b/compiler/rustc_typeck/src/check/check.rs @@ -477,7 +477,7 @@ pub(super) fn check_opaque_for_inheriting_lifetimes( struct ProhibitOpaqueVisitor<'tcx> { opaque_identity_ty: Ty<'tcx>, generics: &'tcx ty::Generics, - }; + } impl<'tcx> ty::fold::TypeVisitor<'tcx> for ProhibitOpaqueVisitor<'tcx> { type BreakTy = Option<Ty<'tcx>>; @@ -746,20 +746,22 @@ pub fn check_item_type<'tcx>(tcx: TyCtxt<'tcx>, it: &'tcx hir::Item<'tcx>) { let generics = tcx.generics_of(def_id); check_type_params_are_used(tcx, &generics, pty_ty); } - hir::ItemKind::ForeignMod(ref m) => { - check_abi(tcx, it.span, m.abi); + hir::ItemKind::ForeignMod { abi, items } => { + check_abi(tcx, it.span, abi); - if m.abi == Abi::RustIntrinsic { - for item in m.items { + if abi == Abi::RustIntrinsic { + for item in items { + let item = tcx.hir().foreign_item(item.id); intrinsic::check_intrinsic_type(tcx, item); } - } else if m.abi == Abi::PlatformIntrinsic { - for item in m.items { + } else if abi == Abi::PlatformIntrinsic { + for item in items { + let item = tcx.hir().foreign_item(item.id); intrinsic::check_platform_intrinsic_type(tcx, item); } } else { - for item in m.items { - let def_id = tcx.hir().local_def_id(item.hir_id); + for item in items { + let def_id = tcx.hir().local_def_id(item.id.hir_id); let generics = tcx.generics_of(def_id); let own_counts = generics.own_counts(); if generics.params.len() - own_counts.lifetimes != 0 { @@ -791,9 +793,10 @@ pub fn check_item_type<'tcx>(tcx: TyCtxt<'tcx>, it: &'tcx hir::Item<'tcx>) { .emit(); } + let item = tcx.hir().foreign_item(item.id); match item.kind { hir::ForeignItemKind::Fn(ref fn_decl, _, _) => { - require_c_abi_if_c_variadic(tcx, fn_decl, m.abi, item.span); + require_c_abi_if_c_variadic(tcx, fn_decl, abi, item.span); } hir::ForeignItemKind::Static(..) => { check_static_inhabited(tcx, def_id, item.span); diff --git a/compiler/rustc_typeck/src/check/expr.rs b/compiler/rustc_typeck/src/check/expr.rs index f7f9e607a74..26962d2222d 100644 --- a/compiler/rustc_typeck/src/check/expr.rs +++ b/compiler/rustc_typeck/src/check/expr.rs @@ -22,7 +22,6 @@ use crate::type_error_struct; use crate::errors::{AddressOfTemporaryTaken, ReturnStmtOutsideOfFnBody, StructExprNonExhaustive}; use rustc_ast as ast; -use rustc_ast::util::lev_distance::find_best_match_for_name; use rustc_data_structures::fx::FxHashMap; use rustc_data_structures::stack::ensure_sufficient_stack; use rustc_errors::ErrorReported; @@ -40,6 +39,7 @@ use rustc_middle::ty::Ty; use rustc_middle::ty::TypeFoldable; use rustc_middle::ty::{AdtKind, Visibility}; use rustc_span::hygiene::DesugaringKind; +use rustc_span::lev_distance::find_best_match_for_name; use rustc_span::source_map::Span; use rustc_span::symbol::{kw, sym, Ident, Symbol}; use rustc_trait_selection::traits::{self, ObligationCauseCode}; @@ -1441,18 +1441,22 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { field: Symbol, skip: Vec<Symbol>, ) -> Option<Symbol> { - let names = variant.fields.iter().filter_map(|field| { - // ignore already set fields and private fields from non-local crates - if skip.iter().any(|&x| x == field.ident.name) - || (!variant.def_id.is_local() && field.vis != Visibility::Public) - { - None - } else { - Some(&field.ident.name) - } - }); + let names = variant + .fields + .iter() + .filter_map(|field| { + // ignore already set fields and private fields from non-local crates + if skip.iter().any(|&x| x == field.ident.name) + || (!variant.def_id.is_local() && field.vis != Visibility::Public) + { + None + } else { + Some(field.ident.name) + } + }) + .collect::<Vec<Symbol>>(); - find_best_match_for_name(names, field, None) + find_best_match_for_name(&names, field, None) } fn available_field_names(&self, variant: &'tcx ty::VariantDef) -> Vec<Symbol> { diff --git a/compiler/rustc_typeck/src/check/method/probe.rs b/compiler/rustc_typeck/src/check/method/probe.rs index 478f8a16169..39a79893b64 100644 --- a/compiler/rustc_typeck/src/check/method/probe.rs +++ b/compiler/rustc_typeck/src/check/method/probe.rs @@ -9,7 +9,6 @@ use crate::hir::def::DefKind; use crate::hir::def_id::DefId; use rustc_ast as ast; -use rustc_ast::util::lev_distance::{find_best_match_for_name, lev_distance}; use rustc_data_structures::fx::FxHashSet; use rustc_data_structures::sync::Lrc; use rustc_hir as hir; @@ -27,6 +26,7 @@ use rustc_middle::ty::{ }; use rustc_session::lint; use rustc_span::def_id::LocalDefId; +use rustc_span::lev_distance::{find_best_match_for_name, lev_distance}; use rustc_span::{symbol::Ident, Span, Symbol, DUMMY_SP}; use rustc_trait_selection::autoderef::{self, Autoderef}; use rustc_trait_selection::traits::query::evaluate_obligation::InferCtxtExt; @@ -1538,8 +1538,11 @@ impl<'a, 'tcx> ProbeContext<'a, 'tcx> { Ok(None) } else { let best_name = { - let names = applicable_close_candidates.iter().map(|cand| &cand.ident.name); - find_best_match_for_name(names, self.method_name.unwrap().name, None) + let names = applicable_close_candidates + .iter() + .map(|cand| cand.ident.name) + .collect::<Vec<Symbol>>(); + find_best_match_for_name(&names, self.method_name.unwrap().name, None) } .unwrap(); Ok(applicable_close_candidates diff --git a/compiler/rustc_typeck/src/check/method/suggest.rs b/compiler/rustc_typeck/src/check/method/suggest.rs index 3d5ce57a491..7ed2933c08b 100644 --- a/compiler/rustc_typeck/src/check/method/suggest.rs +++ b/compiler/rustc_typeck/src/check/method/suggest.rs @@ -2,7 +2,6 @@ //! found or is otherwise invalid. use crate::check::FnCtxt; -use rustc_ast::util::lev_distance; use rustc_data_structures::fx::{FxHashMap, FxHashSet}; use rustc_errors::{pluralize, struct_span_err, Applicability, DiagnosticBuilder}; use rustc_hir as hir; @@ -17,6 +16,7 @@ use rustc_middle::ty::print::with_crate_prefix; use rustc_middle::ty::{ self, ToPolyTraitRef, ToPredicate, Ty, TyCtxt, TypeFoldable, WithConstness, }; +use rustc_span::lev_distance; use rustc_span::symbol::{kw, sym, Ident}; use rustc_span::{source_map, FileName, Span}; use rustc_trait_selection::traits::query::evaluate_obligation::InferCtxtExt; @@ -744,7 +744,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { if actual.is_enum() { let adt_def = actual.ty_adt_def().expect("enum is not an ADT"); if let Some(suggestion) = lev_distance::find_best_match_for_name( - adt_def.variants.iter().map(|s| &s.ident.name), + &adt_def.variants.iter().map(|s| s.ident.name).collect::<Vec<_>>(), item_name.name, None, ) { @@ -1308,6 +1308,8 @@ fn compute_all_traits(tcx: TyCtxt<'_>) -> Vec<DefId> { fn visit_trait_item(&mut self, _trait_item: &hir::TraitItem<'_>) {} fn visit_impl_item(&mut self, _impl_item: &hir::ImplItem<'_>) {} + + fn visit_foreign_item(&mut self, _foreign_item: &hir::ForeignItem<'_>) {} } tcx.hir().krate().visit_all_item_likes(&mut Visitor { map: &tcx.hir(), traits: &mut traits }); diff --git a/compiler/rustc_typeck/src/check/mod.rs b/compiler/rustc_typeck/src/check/mod.rs index 1479eadf1b0..d27a68ccf1b 100644 --- a/compiler/rustc_typeck/src/check/mod.rs +++ b/compiler/rustc_typeck/src/check/mod.rs @@ -1134,6 +1134,7 @@ impl ItemLikeVisitor<'tcx> for CheckItemTypesVisitor<'tcx> { } fn visit_trait_item(&mut self, _: &'tcx hir::TraitItem<'tcx>) {} fn visit_impl_item(&mut self, _: &'tcx hir::ImplItem<'tcx>) {} + fn visit_foreign_item(&mut self, _: &'tcx hir::ForeignItem<'tcx>) {} } fn typeck_item_bodies(tcx: TyCtxt<'_>, crate_num: CrateNum) { diff --git a/compiler/rustc_typeck/src/check/pat.rs b/compiler/rustc_typeck/src/check/pat.rs index a729912126e..bcb73e1b4e7 100644 --- a/compiler/rustc_typeck/src/check/pat.rs +++ b/compiler/rustc_typeck/src/check/pat.rs @@ -1,7 +1,6 @@ use crate::check::FnCtxt; use rustc_ast as ast; -use rustc_ast::util::lev_distance::find_best_match_for_name; use rustc_data_structures::fx::FxHashMap; use rustc_errors::{pluralize, struct_span_err, Applicability, DiagnosticBuilder}; use rustc_hir as hir; @@ -13,6 +12,7 @@ use rustc_infer::infer::type_variable::{TypeVariableOrigin, TypeVariableOriginKi use rustc_middle::ty::subst::GenericArg; use rustc_middle::ty::{self, Adt, BindingMode, Ty, TypeFoldable}; use rustc_span::hygiene::DesugaringKind; +use rustc_span::lev_distance::find_best_match_for_name; use rustc_span::source_map::{Span, Spanned}; use rustc_span::symbol::Ident; use rustc_trait_selection::traits::{ObligationCause, Pattern}; @@ -1302,8 +1302,9 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { ), ); if plural == "" { - let input = unmentioned_fields.iter().map(|(_, field)| &field.name); - let suggested_name = find_best_match_for_name(input, ident.name, None); + let input = + unmentioned_fields.iter().map(|(_, field)| field.name).collect::<Vec<_>>(); + let suggested_name = find_best_match_for_name(&input, ident.name, None); if let Some(suggested_name) = suggested_name { err.span_suggestion( ident.span, diff --git a/compiler/rustc_typeck/src/check/wfcheck.rs b/compiler/rustc_typeck/src/check/wfcheck.rs index aeca801a4ee..c09f8cce5b4 100644 --- a/compiler/rustc_typeck/src/check/wfcheck.rs +++ b/compiler/rustc_typeck/src/check/wfcheck.rs @@ -156,8 +156,9 @@ pub fn check_item_well_formed(tcx: TyCtxt<'_>, def_id: LocalDefId) { hir::ItemKind::Const(ref ty, ..) => { check_item_type(tcx, item.hir_id, ty.span, false); } - hir::ItemKind::ForeignMod(ref module) => { - for it in module.items.iter() { + hir::ItemKind::ForeignMod { items, .. } => { + for it in items.iter() { + let it = tcx.hir().foreign_item(it.id); match it.kind { hir::ForeignItemKind::Fn(ref decl, ..) => { check_item_fn(tcx, it.hir_id, it.ident, it.span, decl) @@ -1345,6 +1346,10 @@ impl ParItemLikeVisitor<'tcx> for CheckTypeWellFormedVisitor<'tcx> { fn visit_impl_item(&self, impl_item: &'tcx hir::ImplItem<'tcx>) { Visitor::visit_impl_item(&mut self.clone(), impl_item); } + + fn visit_foreign_item(&self, foreign_item: &'tcx hir::ForeignItem<'tcx>) { + Visitor::visit_foreign_item(&mut self.clone(), foreign_item) + } } impl Visitor<'tcx> for CheckTypeWellFormedVisitor<'tcx> { diff --git a/compiler/rustc_typeck/src/check/writeback.rs b/compiler/rustc_typeck/src/check/writeback.rs index 335f2cc2716..d1ada123c0d 100644 --- a/compiler/rustc_typeck/src/check/writeback.rs +++ b/compiler/rustc_typeck/src/check/writeback.rs @@ -194,7 +194,9 @@ impl<'cx, 'tcx> WritebackCx<'cx, 'tcx> { let mut typeck_results = self.fcx.typeck_results.borrow_mut(); // All valid indexing looks like this; might encounter non-valid indexes at this point. - let base_ty = typeck_results.expr_ty_adjusted_opt(&base).map(|t| t.kind()); + let base_ty = typeck_results + .expr_ty_adjusted_opt(&base) + .map(|t| self.fcx.resolve_vars_if_possible(t).kind()); if base_ty.is_none() { // When encountering `return [0][0]` outside of a `fn` body we can encounter a base // that isn't in the type table. We assume more relevant errors have already been diff --git a/compiler/rustc_typeck/src/check_unused.rs b/compiler/rustc_typeck/src/check_unused.rs index 4fda8932e21..31121ece898 100644 --- a/compiler/rustc_typeck/src/check_unused.rs +++ b/compiler/rustc_typeck/src/check_unused.rs @@ -35,6 +35,8 @@ impl ItemLikeVisitor<'v> for CheckVisitor<'tcx> { fn visit_trait_item(&mut self, _trait_item: &hir::TraitItem<'_>) {} fn visit_impl_item(&mut self, _impl_item: &hir::ImplItem<'_>) {} + + fn visit_foreign_item(&mut self, _foreign_item: &hir::ForeignItem<'_>) {} } struct CheckVisitor<'tcx> { @@ -225,4 +227,6 @@ impl<'a, 'tcx, 'v> ItemLikeVisitor<'v> for CollectExternCrateVisitor<'a, 'tcx> { fn visit_trait_item(&mut self, _trait_item: &hir::TraitItem<'_>) {} fn visit_impl_item(&mut self, _impl_item: &hir::ImplItem<'_>) {} + + fn visit_foreign_item(&mut self, _foreign_item: &hir::ForeignItem<'_>) {} } diff --git a/compiler/rustc_typeck/src/coherence/inherent_impls.rs b/compiler/rustc_typeck/src/coherence/inherent_impls.rs index 373acb95c9e..483ab2f58f2 100644 --- a/compiler/rustc_typeck/src/coherence/inherent_impls.rs +++ b/compiler/rustc_typeck/src/coherence/inherent_impls.rs @@ -334,6 +334,8 @@ impl ItemLikeVisitor<'v> for InherentCollect<'tcx> { fn visit_trait_item(&mut self, _trait_item: &hir::TraitItem<'_>) {} fn visit_impl_item(&mut self, _impl_item: &hir::ImplItem<'_>) {} + + fn visit_foreign_item(&mut self, _foreign_item: &hir::ForeignItem<'_>) {} } impl InherentCollect<'tcx> { diff --git a/compiler/rustc_typeck/src/coherence/inherent_impls_overlap.rs b/compiler/rustc_typeck/src/coherence/inherent_impls_overlap.rs index ce157f809ef..dd90724e93f 100644 --- a/compiler/rustc_typeck/src/coherence/inherent_impls_overlap.rs +++ b/compiler/rustc_typeck/src/coherence/inherent_impls_overlap.rs @@ -149,4 +149,6 @@ impl ItemLikeVisitor<'v> for InherentOverlapChecker<'tcx> { fn visit_trait_item(&mut self, _trait_item: &hir::TraitItem<'v>) {} fn visit_impl_item(&mut self, _impl_item: &hir::ImplItem<'v>) {} + + fn visit_foreign_item(&mut self, _foreign_item: &hir::ForeignItem<'v>) {} } diff --git a/compiler/rustc_typeck/src/coherence/orphan.rs b/compiler/rustc_typeck/src/coherence/orphan.rs index b2009962aba..253dcf06e01 100644 --- a/compiler/rustc_typeck/src/coherence/orphan.rs +++ b/compiler/rustc_typeck/src/coherence/orphan.rs @@ -244,4 +244,6 @@ impl ItemLikeVisitor<'v> for OrphanChecker<'tcx> { fn visit_trait_item(&mut self, _trait_item: &hir::TraitItem<'_>) {} fn visit_impl_item(&mut self, _impl_item: &hir::ImplItem<'_>) {} + + fn visit_foreign_item(&mut self, _foreign_item: &hir::ForeignItem<'_>) {} } diff --git a/compiler/rustc_typeck/src/coherence/unsafety.rs b/compiler/rustc_typeck/src/coherence/unsafety.rs index b281092ea63..2d9128e7dc0 100644 --- a/compiler/rustc_typeck/src/coherence/unsafety.rs +++ b/compiler/rustc_typeck/src/coherence/unsafety.rs @@ -94,4 +94,6 @@ impl ItemLikeVisitor<'v> for UnsafetyChecker<'tcx> { fn visit_trait_item(&mut self, _trait_item: &hir::TraitItem<'_>) {} fn visit_impl_item(&mut self, _impl_item: &hir::ImplItem<'_>) {} + + fn visit_foreign_item(&mut self, _foreign_item: &hir::ForeignItem<'_>) {} } diff --git a/compiler/rustc_typeck/src/collect.rs b/compiler/rustc_typeck/src/collect.rs index dee0e6c2ebb..0ff10abb60a 100644 --- a/compiler/rustc_typeck/src/collect.rs +++ b/compiler/rustc_typeck/src/collect.rs @@ -646,8 +646,9 @@ fn convert_item(tcx: TyCtxt<'_>, item_id: hir::HirId) { | hir::ItemKind::Use(..) | hir::ItemKind::Mod(_) | hir::ItemKind::GlobalAsm(_) => {} - hir::ItemKind::ForeignMod(ref foreign_mod) => { - for item in foreign_mod.items { + hir::ItemKind::ForeignMod { items, .. } => { + for item in items { + let item = tcx.hir().foreign_item(item.id); let def_id = tcx.hir().local_def_id(item.hir_id); tcx.ensure().generics_of(def_id); tcx.ensure().type_of(def_id); diff --git a/compiler/rustc_typeck/src/collect/type_of.rs b/compiler/rustc_typeck/src/collect/type_of.rs index c4f4c8bc76b..88ba5788b05 100644 --- a/compiler/rustc_typeck/src/collect/type_of.rs +++ b/compiler/rustc_typeck/src/collect/type_of.rs @@ -259,7 +259,7 @@ pub(super) fn type_of(tcx: TyCtxt<'_>, def_id: DefId) -> Ty<'_> { ItemKind::Trait(..) | ItemKind::TraitAlias(..) | ItemKind::Mod(..) - | ItemKind::ForeignMod(..) + | ItemKind::ForeignMod { .. } | ItemKind::GlobalAsm(..) | ItemKind::ExternCrate(..) | ItemKind::Use(..) => { diff --git a/compiler/rustc_typeck/src/impl_wf_check.rs b/compiler/rustc_typeck/src/impl_wf_check.rs index 4901d6041d6..14daa97c2c5 100644 --- a/compiler/rustc_typeck/src/impl_wf_check.rs +++ b/compiler/rustc_typeck/src/impl_wf_check.rs @@ -93,6 +93,8 @@ impl ItemLikeVisitor<'tcx> for ImplWfCheck<'tcx> { fn visit_trait_item(&mut self, _trait_item: &'tcx hir::TraitItem<'tcx>) {} fn visit_impl_item(&mut self, _impl_item: &'tcx hir::ImplItem<'tcx>) {} + + fn visit_foreign_item(&mut self, _foreign_item: &'tcx hir::ForeignItem<'tcx>) {} } fn enforce_impl_params_are_constrained( diff --git a/compiler/rustc_typeck/src/outlives/implicit_infer.rs b/compiler/rustc_typeck/src/outlives/implicit_infer.rs index e7a9e078a73..3d0635e3fe4 100644 --- a/compiler/rustc_typeck/src/outlives/implicit_infer.rs +++ b/compiler/rustc_typeck/src/outlives/implicit_infer.rs @@ -109,6 +109,8 @@ impl<'cx, 'tcx> ItemLikeVisitor<'tcx> for InferVisitor<'cx, 'tcx> { fn visit_trait_item(&mut self, _trait_item: &'tcx hir::TraitItem<'tcx>) {} fn visit_impl_item(&mut self, _impl_item: &'tcx hir::ImplItem<'tcx>) {} + + fn visit_foreign_item(&mut self, _foreign_item: &'tcx hir::ForeignItem<'tcx>) {} } fn insert_required_predicates_to_be_wf<'tcx>( diff --git a/compiler/rustc_typeck/src/outlives/test.rs b/compiler/rustc_typeck/src/outlives/test.rs index abe9319d71c..56d42f756c4 100644 --- a/compiler/rustc_typeck/src/outlives/test.rs +++ b/compiler/rustc_typeck/src/outlives/test.rs @@ -26,4 +26,5 @@ impl ItemLikeVisitor<'tcx> for OutlivesTest<'tcx> { fn visit_trait_item(&mut self, _: &'tcx hir::TraitItem<'tcx>) {} fn visit_impl_item(&mut self, _: &'tcx hir::ImplItem<'tcx>) {} + fn visit_foreign_item(&mut self, _: &'tcx hir::ForeignItem<'tcx>) {} } diff --git a/compiler/rustc_typeck/src/variance/constraints.rs b/compiler/rustc_typeck/src/variance/constraints.rs index b2b062e4095..a8fbdfb7c65 100644 --- a/compiler/rustc_typeck/src/variance/constraints.rs +++ b/compiler/rustc_typeck/src/variance/constraints.rs @@ -92,14 +92,6 @@ impl<'a, 'tcx, 'v> ItemLikeVisitor<'v> for ConstraintContext<'a, 'tcx> { self.visit_node_helper(item.hir_id); } - hir::ItemKind::ForeignMod(ref foreign_mod) => { - for foreign_item in foreign_mod.items { - if let hir::ForeignItemKind::Fn(..) = foreign_item.kind { - self.visit_node_helper(foreign_item.hir_id); - } - } - } - _ => {} } } @@ -115,6 +107,12 @@ impl<'a, 'tcx, 'v> ItemLikeVisitor<'v> for ConstraintContext<'a, 'tcx> { self.visit_node_helper(impl_item.hir_id); } } + + fn visit_foreign_item(&mut self, foreign_item: &hir::ForeignItem<'_>) { + if let hir::ForeignItemKind::Fn(..) = foreign_item.kind { + self.visit_node_helper(foreign_item.hir_id); + } + } } impl<'a, 'tcx> ConstraintContext<'a, 'tcx> { diff --git a/compiler/rustc_typeck/src/variance/terms.rs b/compiler/rustc_typeck/src/variance/terms.rs index 81c858c53cb..3b2a1c24ddd 100644 --- a/compiler/rustc_typeck/src/variance/terms.rs +++ b/compiler/rustc_typeck/src/variance/terms.rs @@ -153,14 +153,6 @@ impl<'a, 'tcx, 'v> ItemLikeVisitor<'v> for TermsContext<'a, 'tcx> { self.add_inferreds_for_item(item.hir_id); } - hir::ItemKind::ForeignMod(ref foreign_mod) => { - for foreign_item in foreign_mod.items { - if let hir::ForeignItemKind::Fn(..) = foreign_item.kind { - self.add_inferreds_for_item(foreign_item.hir_id); - } - } - } - _ => {} } } @@ -176,4 +168,10 @@ impl<'a, 'tcx, 'v> ItemLikeVisitor<'v> for TermsContext<'a, 'tcx> { self.add_inferreds_for_item(impl_item.hir_id); } } + + fn visit_foreign_item(&mut self, foreign_item: &hir::ForeignItem<'_>) { + if let hir::ForeignItemKind::Fn(..) = foreign_item.kind { + self.add_inferreds_for_item(foreign_item.hir_id); + } + } } diff --git a/compiler/rustc_typeck/src/variance/test.rs b/compiler/rustc_typeck/src/variance/test.rs index 1aab89310c6..d6e43b6d669 100644 --- a/compiler/rustc_typeck/src/variance/test.rs +++ b/compiler/rustc_typeck/src/variance/test.rs @@ -26,4 +26,5 @@ impl ItemLikeVisitor<'tcx> for VarianceTest<'tcx> { fn visit_trait_item(&mut self, _: &'tcx hir::TraitItem<'tcx>) {} fn visit_impl_item(&mut self, _: &'tcx hir::ImplItem<'tcx>) {} + fn visit_foreign_item(&mut self, _: &'tcx hir::ForeignItem<'tcx>) {} } |