2967 lines
115 KiB
Rust
2967 lines
115 KiB
Rust
//! "Collection" is the process of determining the type and other external
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//! details of each item in Rust. Collection is specifically concerned
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//! with *inter-procedural* things -- for example, for a function
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//! definition, collection will figure out the type and signature of the
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//! function, but it will not visit the *body* of the function in any way,
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//! nor examine type annotations on local variables (that's the job of
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//! type *checking*).
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//!
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//! Collecting is ultimately defined by a bundle of queries that
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//! inquire after various facts about the items in the crate (e.g.,
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//! `type_of`, `generics_of`, `predicates_of`, etc). See the `provide` function
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//! for the full set.
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//!
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//! At present, however, we do run collection across all items in the
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//! crate as a kind of pass. This should eventually be factored away.
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use crate::astconv::{AstConv, SizedByDefault};
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use crate::bounds::Bounds;
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use crate::check::intrinsic::intrinsic_operation_unsafety;
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use crate::constrained_generic_params as cgp;
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use crate::errors;
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use crate::middle::resolve_lifetime as rl;
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use rustc_ast as ast;
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use rustc_ast::{MetaItemKind, NestedMetaItem};
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use rustc_attr::{list_contains_name, InlineAttr, InstructionSetAttr, OptimizeAttr};
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use rustc_data_structures::captures::Captures;
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use rustc_data_structures::fx::{FxHashMap, FxHashSet, FxIndexSet};
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use rustc_errors::{struct_span_err, Applicability};
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use rustc_hir as hir;
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use rustc_hir::def::{CtorKind, DefKind, Res};
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use rustc_hir::def_id::{DefId, LocalDefId, LOCAL_CRATE};
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use rustc_hir::intravisit::{self, NestedVisitorMap, Visitor};
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use rustc_hir::weak_lang_items;
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use rustc_hir::{GenericParamKind, HirId, Node};
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use rustc_middle::hir::map::blocks::FnLikeNode;
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use rustc_middle::hir::map::Map;
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use rustc_middle::middle::codegen_fn_attrs::{CodegenFnAttrFlags, CodegenFnAttrs};
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use rustc_middle::mir::mono::Linkage;
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use rustc_middle::ty::query::Providers;
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use rustc_middle::ty::subst::InternalSubsts;
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use rustc_middle::ty::util::Discr;
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use rustc_middle::ty::util::IntTypeExt;
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use rustc_middle::ty::{self, AdtKind, Const, DefIdTree, ToPolyTraitRef, Ty, TyCtxt};
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use rustc_middle::ty::{ReprOptions, ToPredicate, WithConstness};
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use rustc_session::config::SanitizerSet;
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use rustc_session::lint;
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use rustc_session::parse::feature_err;
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use rustc_span::symbol::{kw, sym, Ident, Symbol};
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use rustc_span::{Span, DUMMY_SP};
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use rustc_target::spec::abi;
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use rustc_trait_selection::traits::error_reporting::suggestions::NextTypeParamName;
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use std::ops::ControlFlow;
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mod item_bounds;
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mod type_of;
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struct OnlySelfBounds(bool);
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///////////////////////////////////////////////////////////////////////////
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// Main entry point
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fn collect_mod_item_types(tcx: TyCtxt<'_>, module_def_id: LocalDefId) {
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tcx.hir().visit_item_likes_in_module(
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module_def_id,
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&mut CollectItemTypesVisitor { tcx }.as_deep_visitor(),
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);
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}
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pub fn provide(providers: &mut Providers) {
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*providers = Providers {
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opt_const_param_of: type_of::opt_const_param_of,
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type_of: type_of::type_of,
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item_bounds: item_bounds::item_bounds,
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explicit_item_bounds: item_bounds::explicit_item_bounds,
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generics_of,
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predicates_of,
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predicates_defined_on,
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projection_ty_from_predicates,
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explicit_predicates_of,
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super_predicates_of,
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trait_explicit_predicates_and_bounds,
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type_param_predicates,
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trait_def,
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adt_def,
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fn_sig,
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impl_trait_ref,
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impl_polarity,
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is_foreign_item,
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static_mutability,
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generator_kind,
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codegen_fn_attrs,
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collect_mod_item_types,
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..*providers
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};
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}
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///////////////////////////////////////////////////////////////////////////
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/// Context specific to some particular item. This is what implements
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/// `AstConv`. It has information about the predicates that are defined
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/// on the trait. Unfortunately, this predicate information is
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/// available in various different forms at various points in the
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/// process. So we can't just store a pointer to e.g., the AST or the
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/// parsed ty form, we have to be more flexible. To this end, the
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/// `ItemCtxt` is parameterized by a `DefId` that it uses to satisfy
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/// `get_type_parameter_bounds` requests, drawing the information from
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/// the AST (`hir::Generics`), recursively.
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pub struct ItemCtxt<'tcx> {
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tcx: TyCtxt<'tcx>,
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item_def_id: DefId,
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}
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///////////////////////////////////////////////////////////////////////////
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#[derive(Default)]
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crate struct PlaceholderHirTyCollector(crate Vec<Span>);
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impl<'v> Visitor<'v> for PlaceholderHirTyCollector {
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type Map = intravisit::ErasedMap<'v>;
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fn nested_visit_map(&mut self) -> NestedVisitorMap<Self::Map> {
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NestedVisitorMap::None
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}
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fn visit_ty(&mut self, t: &'v hir::Ty<'v>) {
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if let hir::TyKind::Infer = t.kind {
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self.0.push(t.span);
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}
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intravisit::walk_ty(self, t)
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}
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}
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struct CollectItemTypesVisitor<'tcx> {
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tcx: TyCtxt<'tcx>,
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}
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/// If there are any placeholder types (`_`), emit an error explaining that this is not allowed
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/// and suggest adding type parameters in the appropriate place, taking into consideration any and
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/// all already existing generic type parameters to avoid suggesting a name that is already in use.
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crate fn placeholder_type_error(
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tcx: TyCtxt<'tcx>,
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span: Option<Span>,
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generics: &[hir::GenericParam<'_>],
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placeholder_types: Vec<Span>,
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suggest: bool,
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) {
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if placeholder_types.is_empty() {
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return;
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}
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let type_name = generics.next_type_param_name(None);
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let mut sugg: Vec<_> =
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placeholder_types.iter().map(|sp| (*sp, (*type_name).to_string())).collect();
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if generics.is_empty() {
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if let Some(span) = span {
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sugg.push((span, format!("<{}>", type_name)));
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}
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} else if let Some(arg) = generics
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.iter()
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.find(|arg| matches!(arg.name, hir::ParamName::Plain(Ident { name: kw::Underscore, .. })))
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{
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// Account for `_` already present in cases like `struct S<_>(_);` and suggest
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// `struct S<T>(T);` instead of `struct S<_, T>(T);`.
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sugg.push((arg.span, (*type_name).to_string()));
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} else {
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let last = generics.iter().last().unwrap();
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sugg.push((
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// Account for bounds, we want `fn foo<T: E, K>(_: K)` not `fn foo<T, K: E>(_: K)`.
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last.bounds_span().unwrap_or(last.span).shrink_to_hi(),
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format!(", {}", type_name),
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));
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}
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let mut err = bad_placeholder_type(tcx, placeholder_types);
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if suggest {
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err.multipart_suggestion(
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"use type parameters instead",
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sugg,
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Applicability::HasPlaceholders,
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);
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}
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err.emit();
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}
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fn reject_placeholder_type_signatures_in_item(tcx: TyCtxt<'tcx>, item: &'tcx hir::Item<'tcx>) {
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let (generics, suggest) = match &item.kind {
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hir::ItemKind::Union(_, generics)
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| hir::ItemKind::Enum(_, generics)
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| hir::ItemKind::TraitAlias(generics, _)
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| hir::ItemKind::Trait(_, _, generics, ..)
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| hir::ItemKind::Impl { generics, .. }
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| hir::ItemKind::Struct(_, generics) => (generics, true),
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hir::ItemKind::OpaqueTy(hir::OpaqueTy { generics, .. })
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| hir::ItemKind::TyAlias(_, generics) => (generics, false),
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// `static`, `fn` and `const` are handled elsewhere to suggest appropriate type.
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_ => return,
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};
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let mut visitor = PlaceholderHirTyCollector::default();
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visitor.visit_item(item);
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placeholder_type_error(tcx, Some(generics.span), &generics.params[..], visitor.0, suggest);
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}
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impl Visitor<'tcx> for CollectItemTypesVisitor<'tcx> {
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type Map = Map<'tcx>;
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fn nested_visit_map(&mut self) -> NestedVisitorMap<Self::Map> {
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NestedVisitorMap::OnlyBodies(self.tcx.hir())
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}
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fn visit_item(&mut self, item: &'tcx hir::Item<'tcx>) {
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convert_item(self.tcx, item.hir_id);
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reject_placeholder_type_signatures_in_item(self.tcx, item);
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intravisit::walk_item(self, item);
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}
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fn visit_generics(&mut self, generics: &'tcx hir::Generics<'tcx>) {
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for param in generics.params {
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match param.kind {
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hir::GenericParamKind::Lifetime { .. } => {}
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hir::GenericParamKind::Type { default: Some(_), .. } => {
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let def_id = self.tcx.hir().local_def_id(param.hir_id);
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self.tcx.ensure().type_of(def_id);
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}
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hir::GenericParamKind::Type { .. } => {}
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hir::GenericParamKind::Const { .. } => {
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let def_id = self.tcx.hir().local_def_id(param.hir_id);
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self.tcx.ensure().type_of(def_id);
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// FIXME(const_generics:defaults)
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}
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}
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}
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intravisit::walk_generics(self, generics);
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}
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fn visit_expr(&mut self, expr: &'tcx hir::Expr<'tcx>) {
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if let hir::ExprKind::Closure(..) = expr.kind {
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let def_id = self.tcx.hir().local_def_id(expr.hir_id);
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self.tcx.ensure().generics_of(def_id);
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self.tcx.ensure().type_of(def_id);
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}
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intravisit::walk_expr(self, expr);
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}
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fn visit_trait_item(&mut self, trait_item: &'tcx hir::TraitItem<'tcx>) {
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convert_trait_item(self.tcx, trait_item.hir_id);
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intravisit::walk_trait_item(self, trait_item);
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}
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fn visit_impl_item(&mut self, impl_item: &'tcx hir::ImplItem<'tcx>) {
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convert_impl_item(self.tcx, impl_item.hir_id);
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intravisit::walk_impl_item(self, impl_item);
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}
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}
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///////////////////////////////////////////////////////////////////////////
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// Utility types and common code for the above passes.
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fn bad_placeholder_type(
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tcx: TyCtxt<'tcx>,
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mut spans: Vec<Span>,
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) -> rustc_errors::DiagnosticBuilder<'tcx> {
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spans.sort();
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let mut err = struct_span_err!(
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tcx.sess,
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spans.clone(),
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E0121,
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"the type placeholder `_` is not allowed within types on item signatures",
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);
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for span in spans {
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err.span_label(span, "not allowed in type signatures");
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}
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err
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}
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impl ItemCtxt<'tcx> {
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pub fn new(tcx: TyCtxt<'tcx>, item_def_id: DefId) -> ItemCtxt<'tcx> {
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ItemCtxt { tcx, item_def_id }
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}
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pub fn to_ty(&self, ast_ty: &'tcx hir::Ty<'tcx>) -> Ty<'tcx> {
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AstConv::ast_ty_to_ty(self, ast_ty)
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}
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pub fn hir_id(&self) -> hir::HirId {
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self.tcx.hir().local_def_id_to_hir_id(self.item_def_id.expect_local())
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}
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pub fn node(&self) -> hir::Node<'tcx> {
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self.tcx.hir().get(self.hir_id())
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}
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}
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impl AstConv<'tcx> for ItemCtxt<'tcx> {
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fn tcx(&self) -> TyCtxt<'tcx> {
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self.tcx
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}
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fn item_def_id(&self) -> Option<DefId> {
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Some(self.item_def_id)
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}
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fn default_constness_for_trait_bounds(&self) -> hir::Constness {
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if let Some(fn_like) = FnLikeNode::from_node(self.node()) {
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fn_like.constness()
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} else {
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hir::Constness::NotConst
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}
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}
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fn get_type_parameter_bounds(&self, span: Span, def_id: DefId) -> ty::GenericPredicates<'tcx> {
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self.tcx.at(span).type_param_predicates((self.item_def_id, def_id.expect_local()))
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}
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fn re_infer(&self, _: Option<&ty::GenericParamDef>, _: Span) -> Option<ty::Region<'tcx>> {
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None
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}
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fn allow_ty_infer(&self) -> bool {
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false
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}
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fn ty_infer(&self, _: Option<&ty::GenericParamDef>, span: Span) -> Ty<'tcx> {
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self.tcx().ty_error_with_message(span, "bad_placeholder_type")
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}
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fn ct_infer(
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&self,
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ty: Ty<'tcx>,
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_: Option<&ty::GenericParamDef>,
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span: Span,
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) -> &'tcx Const<'tcx> {
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bad_placeholder_type(self.tcx(), vec![span]).emit();
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self.tcx().const_error(ty)
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}
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fn projected_ty_from_poly_trait_ref(
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&self,
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span: Span,
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item_def_id: DefId,
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item_segment: &hir::PathSegment<'_>,
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poly_trait_ref: ty::PolyTraitRef<'tcx>,
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) -> Ty<'tcx> {
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if let Some(trait_ref) = poly_trait_ref.no_bound_vars() {
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let item_substs = <dyn AstConv<'tcx>>::create_substs_for_associated_item(
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self,
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self.tcx,
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span,
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item_def_id,
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item_segment,
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trait_ref.substs,
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);
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self.tcx().mk_projection(item_def_id, item_substs)
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} else {
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// There are no late-bound regions; we can just ignore the binder.
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let mut err = struct_span_err!(
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self.tcx().sess,
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span,
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E0212,
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"cannot use the associated type of a trait \
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with uninferred generic parameters"
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);
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match self.node() {
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hir::Node::Field(_) | hir::Node::Ctor(_) | hir::Node::Variant(_) => {
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let item =
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self.tcx.hir().expect_item(self.tcx.hir().get_parent_item(self.hir_id()));
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match &item.kind {
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hir::ItemKind::Enum(_, generics)
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|
| hir::ItemKind::Struct(_, generics)
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| hir::ItemKind::Union(_, generics) => {
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let lt_name = get_new_lifetime_name(self.tcx, poly_trait_ref, generics);
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let (lt_sp, sugg) = match &generics.params[..] {
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[] => (generics.span, format!("<{}>", lt_name)),
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|
[bound, ..] => {
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|
(bound.span.shrink_to_lo(), format!("{}, ", lt_name))
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|
}
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|
};
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|
let suggestions = vec![
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(lt_sp, sugg),
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(
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span,
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format!(
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"{}::{}",
|
|
// Replace the existing lifetimes with a new named lifetime.
|
|
self.tcx
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|
.replace_late_bound_regions(poly_trait_ref, |_| {
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|
self.tcx.mk_region(ty::ReEarlyBound(
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|
ty::EarlyBoundRegion {
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|
def_id: item_def_id,
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|
index: 0,
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|
name: Symbol::intern(<_name),
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|
},
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|
))
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|
})
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|
.0,
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|
item_segment.ident
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|
),
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|
),
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|
];
|
|
err.multipart_suggestion(
|
|
"use a fully qualified path with explicit lifetimes",
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|
suggestions,
|
|
Applicability::MaybeIncorrect,
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|
);
|
|
}
|
|
_ => {}
|
|
}
|
|
}
|
|
hir::Node::Item(hir::Item {
|
|
kind:
|
|
hir::ItemKind::Struct(..) | hir::ItemKind::Enum(..) | hir::ItemKind::Union(..),
|
|
..
|
|
}) => {}
|
|
hir::Node::Item(_)
|
|
| hir::Node::ForeignItem(_)
|
|
| hir::Node::TraitItem(_)
|
|
| hir::Node::ImplItem(_) => {
|
|
err.span_suggestion(
|
|
span,
|
|
"use a fully qualified path with inferred lifetimes",
|
|
format!(
|
|
"{}::{}",
|
|
// Erase named lt, we want `<A as B<'_>::C`, not `<A as B<'a>::C`.
|
|
self.tcx.anonymize_late_bound_regions(poly_trait_ref).skip_binder(),
|
|
item_segment.ident
|
|
),
|
|
Applicability::MaybeIncorrect,
|
|
);
|
|
}
|
|
_ => {}
|
|
}
|
|
err.emit();
|
|
self.tcx().ty_error()
|
|
}
|
|
}
|
|
|
|
fn normalize_ty(&self, _span: Span, ty: Ty<'tcx>) -> Ty<'tcx> {
|
|
// Types in item signatures are not normalized to avoid undue dependencies.
|
|
ty
|
|
}
|
|
|
|
fn set_tainted_by_errors(&self) {
|
|
// There's no obvious place to track this, so just let it go.
|
|
}
|
|
|
|
fn record_ty(&self, _hir_id: hir::HirId, _ty: Ty<'tcx>, _span: Span) {
|
|
// There's no place to record types from signatures?
|
|
}
|
|
}
|
|
|
|
/// Synthesize a new lifetime name that doesn't clash with any of the lifetimes already present.
|
|
fn get_new_lifetime_name<'tcx>(
|
|
tcx: TyCtxt<'tcx>,
|
|
poly_trait_ref: ty::PolyTraitRef<'tcx>,
|
|
generics: &hir::Generics<'tcx>,
|
|
) -> String {
|
|
let existing_lifetimes = tcx
|
|
.collect_referenced_late_bound_regions(&poly_trait_ref)
|
|
.into_iter()
|
|
.filter_map(|lt| {
|
|
if let ty::BoundRegionKind::BrNamed(_, name) = lt {
|
|
Some(name.as_str().to_string())
|
|
} else {
|
|
None
|
|
}
|
|
})
|
|
.chain(generics.params.iter().filter_map(|param| {
|
|
if let hir::GenericParamKind::Lifetime { .. } = ¶m.kind {
|
|
Some(param.name.ident().as_str().to_string())
|
|
} else {
|
|
None
|
|
}
|
|
}))
|
|
.collect::<FxHashSet<String>>();
|
|
|
|
let a_to_z_repeat_n = |n| {
|
|
(b'a'..=b'z').map(move |c| {
|
|
let mut s = '\''.to_string();
|
|
s.extend(std::iter::repeat(char::from(c)).take(n));
|
|
s
|
|
})
|
|
};
|
|
|
|
// If all single char lifetime names are present, we wrap around and double the chars.
|
|
(1..).flat_map(a_to_z_repeat_n).find(|lt| !existing_lifetimes.contains(lt.as_str())).unwrap()
|
|
}
|
|
|
|
/// Returns the predicates defined on `item_def_id` of the form
|
|
/// `X: Foo` where `X` is the type parameter `def_id`.
|
|
fn type_param_predicates(
|
|
tcx: TyCtxt<'_>,
|
|
(item_def_id, def_id): (DefId, LocalDefId),
|
|
) -> ty::GenericPredicates<'_> {
|
|
use rustc_hir::*;
|
|
|
|
// In the AST, bounds can derive from two places. Either
|
|
// written inline like `<T: Foo>` or in a where-clause like
|
|
// `where T: Foo`.
|
|
|
|
let param_id = tcx.hir().local_def_id_to_hir_id(def_id);
|
|
let param_owner = tcx.hir().ty_param_owner(param_id);
|
|
let param_owner_def_id = tcx.hir().local_def_id(param_owner);
|
|
let generics = tcx.generics_of(param_owner_def_id);
|
|
let index = generics.param_def_id_to_index[&def_id.to_def_id()];
|
|
let ty = tcx.mk_ty_param(index, tcx.hir().ty_param_name(param_id));
|
|
|
|
// Don't look for bounds where the type parameter isn't in scope.
|
|
let parent = if item_def_id == param_owner_def_id.to_def_id() {
|
|
None
|
|
} else {
|
|
tcx.generics_of(item_def_id).parent
|
|
};
|
|
|
|
let mut result = parent
|
|
.map(|parent| {
|
|
let icx = ItemCtxt::new(tcx, parent);
|
|
icx.get_type_parameter_bounds(DUMMY_SP, def_id.to_def_id())
|
|
})
|
|
.unwrap_or_default();
|
|
let mut extend = None;
|
|
|
|
let item_hir_id = tcx.hir().local_def_id_to_hir_id(item_def_id.expect_local());
|
|
let ast_generics = match tcx.hir().get(item_hir_id) {
|
|
Node::TraitItem(item) => &item.generics,
|
|
|
|
Node::ImplItem(item) => &item.generics,
|
|
|
|
Node::Item(item) => {
|
|
match item.kind {
|
|
ItemKind::Fn(.., ref generics, _)
|
|
| ItemKind::Impl { ref generics, .. }
|
|
| ItemKind::TyAlias(_, ref generics)
|
|
| ItemKind::OpaqueTy(OpaqueTy { ref generics, impl_trait_fn: None, .. })
|
|
| ItemKind::Enum(_, ref generics)
|
|
| ItemKind::Struct(_, ref generics)
|
|
| ItemKind::Union(_, ref generics) => generics,
|
|
ItemKind::Trait(_, _, ref generics, ..) => {
|
|
// Implied `Self: Trait` and supertrait bounds.
|
|
if param_id == item_hir_id {
|
|
let identity_trait_ref = ty::TraitRef::identity(tcx, item_def_id);
|
|
extend =
|
|
Some((identity_trait_ref.without_const().to_predicate(tcx), item.span));
|
|
}
|
|
generics
|
|
}
|
|
_ => return result,
|
|
}
|
|
}
|
|
|
|
Node::ForeignItem(item) => match item.kind {
|
|
ForeignItemKind::Fn(_, _, ref generics) => generics,
|
|
_ => return result,
|
|
},
|
|
|
|
_ => return result,
|
|
};
|
|
|
|
let icx = ItemCtxt::new(tcx, item_def_id);
|
|
let extra_predicates = extend.into_iter().chain(
|
|
icx.type_parameter_bounds_in_generics(ast_generics, param_id, ty, OnlySelfBounds(true))
|
|
.into_iter()
|
|
.filter(|(predicate, _)| match predicate.skip_binders() {
|
|
ty::PredicateAtom::Trait(data, _) => data.self_ty().is_param(index),
|
|
_ => false,
|
|
}),
|
|
);
|
|
result.predicates =
|
|
tcx.arena.alloc_from_iter(result.predicates.iter().copied().chain(extra_predicates));
|
|
result
|
|
}
|
|
|
|
impl ItemCtxt<'tcx> {
|
|
/// Finds bounds from `hir::Generics`. This requires scanning through the
|
|
/// AST. We do this to avoid having to convert *all* the bounds, which
|
|
/// would create artificial cycles. Instead, we can only convert the
|
|
/// bounds for a type parameter `X` if `X::Foo` is used.
|
|
fn type_parameter_bounds_in_generics(
|
|
&self,
|
|
ast_generics: &'tcx hir::Generics<'tcx>,
|
|
param_id: hir::HirId,
|
|
ty: Ty<'tcx>,
|
|
only_self_bounds: OnlySelfBounds,
|
|
) -> Vec<(ty::Predicate<'tcx>, Span)> {
|
|
let constness = self.default_constness_for_trait_bounds();
|
|
let from_ty_params = ast_generics
|
|
.params
|
|
.iter()
|
|
.filter_map(|param| match param.kind {
|
|
GenericParamKind::Type { .. } if param.hir_id == param_id => Some(¶m.bounds),
|
|
_ => None,
|
|
})
|
|
.flat_map(|bounds| bounds.iter())
|
|
.flat_map(|b| predicates_from_bound(self, ty, b, constness));
|
|
|
|
let from_where_clauses = ast_generics
|
|
.where_clause
|
|
.predicates
|
|
.iter()
|
|
.filter_map(|wp| match *wp {
|
|
hir::WherePredicate::BoundPredicate(ref bp) => Some(bp),
|
|
_ => None,
|
|
})
|
|
.flat_map(|bp| {
|
|
let bt = if is_param(self.tcx, &bp.bounded_ty, param_id) {
|
|
Some(ty)
|
|
} else if !only_self_bounds.0 {
|
|
Some(self.to_ty(&bp.bounded_ty))
|
|
} else {
|
|
None
|
|
};
|
|
bp.bounds.iter().filter_map(move |b| bt.map(|bt| (bt, b)))
|
|
})
|
|
.flat_map(|(bt, b)| predicates_from_bound(self, bt, b, constness));
|
|
|
|
from_ty_params.chain(from_where_clauses).collect()
|
|
}
|
|
}
|
|
|
|
/// Tests whether this is the AST for a reference to the type
|
|
/// parameter with ID `param_id`. We use this so as to avoid running
|
|
/// `ast_ty_to_ty`, because we want to avoid triggering an all-out
|
|
/// conversion of the type to avoid inducing unnecessary cycles.
|
|
fn is_param(tcx: TyCtxt<'_>, ast_ty: &hir::Ty<'_>, param_id: hir::HirId) -> bool {
|
|
if let hir::TyKind::Path(hir::QPath::Resolved(None, ref path)) = ast_ty.kind {
|
|
match path.res {
|
|
Res::SelfTy(Some(def_id), None) | Res::Def(DefKind::TyParam, def_id) => {
|
|
def_id == tcx.hir().local_def_id(param_id).to_def_id()
|
|
}
|
|
_ => false,
|
|
}
|
|
} else {
|
|
false
|
|
}
|
|
}
|
|
|
|
fn convert_item(tcx: TyCtxt<'_>, item_id: hir::HirId) {
|
|
let it = tcx.hir().expect_item(item_id);
|
|
debug!("convert: item {} with id {}", it.ident, it.hir_id);
|
|
let def_id = tcx.hir().local_def_id(item_id);
|
|
match it.kind {
|
|
// These don't define types.
|
|
hir::ItemKind::ExternCrate(_)
|
|
| hir::ItemKind::Use(..)
|
|
| hir::ItemKind::Mod(_)
|
|
| hir::ItemKind::GlobalAsm(_) => {}
|
|
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);
|
|
tcx.ensure().predicates_of(def_id);
|
|
if let hir::ForeignItemKind::Fn(..) = item.kind {
|
|
tcx.ensure().fn_sig(def_id);
|
|
}
|
|
}
|
|
}
|
|
hir::ItemKind::Enum(ref enum_definition, _) => {
|
|
tcx.ensure().generics_of(def_id);
|
|
tcx.ensure().type_of(def_id);
|
|
tcx.ensure().predicates_of(def_id);
|
|
convert_enum_variant_types(tcx, def_id.to_def_id(), &enum_definition.variants);
|
|
}
|
|
hir::ItemKind::Impl { .. } => {
|
|
tcx.ensure().generics_of(def_id);
|
|
tcx.ensure().type_of(def_id);
|
|
tcx.ensure().impl_trait_ref(def_id);
|
|
tcx.ensure().predicates_of(def_id);
|
|
}
|
|
hir::ItemKind::Trait(..) => {
|
|
tcx.ensure().generics_of(def_id);
|
|
tcx.ensure().trait_def(def_id);
|
|
tcx.at(it.span).super_predicates_of(def_id);
|
|
tcx.ensure().predicates_of(def_id);
|
|
}
|
|
hir::ItemKind::TraitAlias(..) => {
|
|
tcx.ensure().generics_of(def_id);
|
|
tcx.at(it.span).super_predicates_of(def_id);
|
|
tcx.ensure().predicates_of(def_id);
|
|
}
|
|
hir::ItemKind::Struct(ref struct_def, _) | hir::ItemKind::Union(ref struct_def, _) => {
|
|
tcx.ensure().generics_of(def_id);
|
|
tcx.ensure().type_of(def_id);
|
|
tcx.ensure().predicates_of(def_id);
|
|
|
|
for f in struct_def.fields() {
|
|
let def_id = tcx.hir().local_def_id(f.hir_id);
|
|
tcx.ensure().generics_of(def_id);
|
|
tcx.ensure().type_of(def_id);
|
|
tcx.ensure().predicates_of(def_id);
|
|
}
|
|
|
|
if let Some(ctor_hir_id) = struct_def.ctor_hir_id() {
|
|
convert_variant_ctor(tcx, ctor_hir_id);
|
|
}
|
|
}
|
|
|
|
// Desugared from `impl Trait`, so visited by the function's return type.
|
|
hir::ItemKind::OpaqueTy(hir::OpaqueTy { impl_trait_fn: Some(_), .. }) => {}
|
|
|
|
// Don't call `type_of` on opaque types, since that depends on type
|
|
// checking function bodies. `check_item_type` ensures that it's called
|
|
// instead.
|
|
hir::ItemKind::OpaqueTy(..) => {
|
|
tcx.ensure().generics_of(def_id);
|
|
tcx.ensure().predicates_of(def_id);
|
|
tcx.ensure().explicit_item_bounds(def_id);
|
|
}
|
|
hir::ItemKind::TyAlias(..)
|
|
| hir::ItemKind::Static(..)
|
|
| hir::ItemKind::Const(..)
|
|
| hir::ItemKind::Fn(..) => {
|
|
tcx.ensure().generics_of(def_id);
|
|
tcx.ensure().type_of(def_id);
|
|
tcx.ensure().predicates_of(def_id);
|
|
match it.kind {
|
|
hir::ItemKind::Fn(..) => tcx.ensure().fn_sig(def_id),
|
|
hir::ItemKind::OpaqueTy(..) => tcx.ensure().item_bounds(def_id),
|
|
_ => (),
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
fn convert_trait_item(tcx: TyCtxt<'_>, trait_item_id: hir::HirId) {
|
|
let trait_item = tcx.hir().expect_trait_item(trait_item_id);
|
|
let def_id = tcx.hir().local_def_id(trait_item.hir_id);
|
|
tcx.ensure().generics_of(def_id);
|
|
|
|
match trait_item.kind {
|
|
hir::TraitItemKind::Fn(..) => {
|
|
tcx.ensure().type_of(def_id);
|
|
tcx.ensure().fn_sig(def_id);
|
|
}
|
|
|
|
hir::TraitItemKind::Const(.., Some(_)) => {
|
|
tcx.ensure().type_of(def_id);
|
|
}
|
|
|
|
hir::TraitItemKind::Const(..) => {
|
|
tcx.ensure().type_of(def_id);
|
|
// Account for `const C: _;`.
|
|
let mut visitor = PlaceholderHirTyCollector::default();
|
|
visitor.visit_trait_item(trait_item);
|
|
placeholder_type_error(tcx, None, &[], visitor.0, false);
|
|
}
|
|
|
|
hir::TraitItemKind::Type(_, Some(_)) => {
|
|
tcx.ensure().item_bounds(def_id);
|
|
tcx.ensure().type_of(def_id);
|
|
// Account for `type T = _;`.
|
|
let mut visitor = PlaceholderHirTyCollector::default();
|
|
visitor.visit_trait_item(trait_item);
|
|
placeholder_type_error(tcx, None, &[], visitor.0, false);
|
|
}
|
|
|
|
hir::TraitItemKind::Type(_, None) => {
|
|
tcx.ensure().item_bounds(def_id);
|
|
// #74612: Visit and try to find bad placeholders
|
|
// even if there is no concrete type.
|
|
let mut visitor = PlaceholderHirTyCollector::default();
|
|
visitor.visit_trait_item(trait_item);
|
|
placeholder_type_error(tcx, None, &[], visitor.0, false);
|
|
}
|
|
};
|
|
|
|
tcx.ensure().predicates_of(def_id);
|
|
}
|
|
|
|
fn convert_impl_item(tcx: TyCtxt<'_>, impl_item_id: hir::HirId) {
|
|
let def_id = tcx.hir().local_def_id(impl_item_id);
|
|
tcx.ensure().generics_of(def_id);
|
|
tcx.ensure().type_of(def_id);
|
|
tcx.ensure().predicates_of(def_id);
|
|
let impl_item = tcx.hir().expect_impl_item(impl_item_id);
|
|
match impl_item.kind {
|
|
hir::ImplItemKind::Fn(..) => {
|
|
tcx.ensure().fn_sig(def_id);
|
|
}
|
|
hir::ImplItemKind::TyAlias(_) => {
|
|
// Account for `type T = _;`
|
|
let mut visitor = PlaceholderHirTyCollector::default();
|
|
visitor.visit_impl_item(impl_item);
|
|
placeholder_type_error(tcx, None, &[], visitor.0, false);
|
|
}
|
|
hir::ImplItemKind::Const(..) => {}
|
|
}
|
|
}
|
|
|
|
fn convert_variant_ctor(tcx: TyCtxt<'_>, ctor_id: hir::HirId) {
|
|
let def_id = tcx.hir().local_def_id(ctor_id);
|
|
tcx.ensure().generics_of(def_id);
|
|
tcx.ensure().type_of(def_id);
|
|
tcx.ensure().predicates_of(def_id);
|
|
}
|
|
|
|
fn convert_enum_variant_types(tcx: TyCtxt<'_>, def_id: DefId, variants: &[hir::Variant<'_>]) {
|
|
let def = tcx.adt_def(def_id);
|
|
let repr_type = def.repr.discr_type();
|
|
let initial = repr_type.initial_discriminant(tcx);
|
|
let mut prev_discr = None::<Discr<'_>>;
|
|
|
|
// fill the discriminant values and field types
|
|
for variant in variants {
|
|
let wrapped_discr = prev_discr.map_or(initial, |d| d.wrap_incr(tcx));
|
|
prev_discr = Some(
|
|
if let Some(ref e) = variant.disr_expr {
|
|
let expr_did = tcx.hir().local_def_id(e.hir_id);
|
|
def.eval_explicit_discr(tcx, expr_did.to_def_id())
|
|
} else if let Some(discr) = repr_type.disr_incr(tcx, prev_discr) {
|
|
Some(discr)
|
|
} else {
|
|
struct_span_err!(tcx.sess, variant.span, E0370, "enum discriminant overflowed")
|
|
.span_label(
|
|
variant.span,
|
|
format!("overflowed on value after {}", prev_discr.unwrap()),
|
|
)
|
|
.note(&format!(
|
|
"explicitly set `{} = {}` if that is desired outcome",
|
|
variant.ident, wrapped_discr
|
|
))
|
|
.emit();
|
|
None
|
|
}
|
|
.unwrap_or(wrapped_discr),
|
|
);
|
|
|
|
for f in variant.data.fields() {
|
|
let def_id = tcx.hir().local_def_id(f.hir_id);
|
|
tcx.ensure().generics_of(def_id);
|
|
tcx.ensure().type_of(def_id);
|
|
tcx.ensure().predicates_of(def_id);
|
|
}
|
|
|
|
// Convert the ctor, if any. This also registers the variant as
|
|
// an item.
|
|
if let Some(ctor_hir_id) = variant.data.ctor_hir_id() {
|
|
convert_variant_ctor(tcx, ctor_hir_id);
|
|
}
|
|
}
|
|
}
|
|
|
|
fn convert_variant(
|
|
tcx: TyCtxt<'_>,
|
|
variant_did: Option<LocalDefId>,
|
|
ctor_did: Option<LocalDefId>,
|
|
ident: Ident,
|
|
discr: ty::VariantDiscr,
|
|
def: &hir::VariantData<'_>,
|
|
adt_kind: ty::AdtKind,
|
|
parent_did: LocalDefId,
|
|
) -> ty::VariantDef {
|
|
let mut seen_fields: FxHashMap<Ident, Span> = Default::default();
|
|
let fields = def
|
|
.fields()
|
|
.iter()
|
|
.map(|f| {
|
|
let fid = tcx.hir().local_def_id(f.hir_id);
|
|
let dup_span = seen_fields.get(&f.ident.normalize_to_macros_2_0()).cloned();
|
|
if let Some(prev_span) = dup_span {
|
|
tcx.sess.emit_err(errors::FieldAlreadyDeclared {
|
|
field_name: f.ident,
|
|
span: f.span,
|
|
prev_span,
|
|
});
|
|
} else {
|
|
seen_fields.insert(f.ident.normalize_to_macros_2_0(), f.span);
|
|
}
|
|
|
|
ty::FieldDef { did: fid.to_def_id(), ident: f.ident, vis: tcx.visibility(fid) }
|
|
})
|
|
.collect();
|
|
let recovered = match def {
|
|
hir::VariantData::Struct(_, r) => *r,
|
|
_ => false,
|
|
};
|
|
ty::VariantDef::new(
|
|
ident,
|
|
variant_did.map(LocalDefId::to_def_id),
|
|
ctor_did.map(LocalDefId::to_def_id),
|
|
discr,
|
|
fields,
|
|
CtorKind::from_hir(def),
|
|
adt_kind,
|
|
parent_did.to_def_id(),
|
|
recovered,
|
|
adt_kind == AdtKind::Struct && tcx.has_attr(parent_did.to_def_id(), sym::non_exhaustive)
|
|
|| variant_did.map_or(false, |variant_did| {
|
|
tcx.has_attr(variant_did.to_def_id(), sym::non_exhaustive)
|
|
}),
|
|
)
|
|
}
|
|
|
|
fn adt_def(tcx: TyCtxt<'_>, def_id: DefId) -> &ty::AdtDef {
|
|
use rustc_hir::*;
|
|
|
|
let def_id = def_id.expect_local();
|
|
let hir_id = tcx.hir().local_def_id_to_hir_id(def_id);
|
|
let item = match tcx.hir().get(hir_id) {
|
|
Node::Item(item) => item,
|
|
_ => bug!(),
|
|
};
|
|
|
|
let repr = ReprOptions::new(tcx, def_id.to_def_id());
|
|
let (kind, variants) = match item.kind {
|
|
ItemKind::Enum(ref def, _) => {
|
|
let mut distance_from_explicit = 0;
|
|
let variants = def
|
|
.variants
|
|
.iter()
|
|
.map(|v| {
|
|
let variant_did = Some(tcx.hir().local_def_id(v.id));
|
|
let ctor_did =
|
|
v.data.ctor_hir_id().map(|hir_id| tcx.hir().local_def_id(hir_id));
|
|
|
|
let discr = if let Some(ref e) = v.disr_expr {
|
|
distance_from_explicit = 0;
|
|
ty::VariantDiscr::Explicit(tcx.hir().local_def_id(e.hir_id).to_def_id())
|
|
} else {
|
|
ty::VariantDiscr::Relative(distance_from_explicit)
|
|
};
|
|
distance_from_explicit += 1;
|
|
|
|
convert_variant(
|
|
tcx,
|
|
variant_did,
|
|
ctor_did,
|
|
v.ident,
|
|
discr,
|
|
&v.data,
|
|
AdtKind::Enum,
|
|
def_id,
|
|
)
|
|
})
|
|
.collect();
|
|
|
|
(AdtKind::Enum, variants)
|
|
}
|
|
ItemKind::Struct(ref def, _) => {
|
|
let variant_did = None::<LocalDefId>;
|
|
let ctor_did = def.ctor_hir_id().map(|hir_id| tcx.hir().local_def_id(hir_id));
|
|
|
|
let variants = std::iter::once(convert_variant(
|
|
tcx,
|
|
variant_did,
|
|
ctor_did,
|
|
item.ident,
|
|
ty::VariantDiscr::Relative(0),
|
|
def,
|
|
AdtKind::Struct,
|
|
def_id,
|
|
))
|
|
.collect();
|
|
|
|
(AdtKind::Struct, variants)
|
|
}
|
|
ItemKind::Union(ref def, _) => {
|
|
let variant_did = None;
|
|
let ctor_did = def.ctor_hir_id().map(|hir_id| tcx.hir().local_def_id(hir_id));
|
|
|
|
let variants = std::iter::once(convert_variant(
|
|
tcx,
|
|
variant_did,
|
|
ctor_did,
|
|
item.ident,
|
|
ty::VariantDiscr::Relative(0),
|
|
def,
|
|
AdtKind::Union,
|
|
def_id,
|
|
))
|
|
.collect();
|
|
|
|
(AdtKind::Union, variants)
|
|
}
|
|
_ => bug!(),
|
|
};
|
|
tcx.alloc_adt_def(def_id.to_def_id(), kind, variants, repr)
|
|
}
|
|
|
|
/// Ensures that the super-predicates of the trait with a `DefId`
|
|
/// of `trait_def_id` are converted and stored. This also ensures that
|
|
/// the transitive super-predicates are converted.
|
|
fn super_predicates_of(tcx: TyCtxt<'_>, trait_def_id: DefId) -> ty::GenericPredicates<'_> {
|
|
debug!("super_predicates(trait_def_id={:?})", trait_def_id);
|
|
let trait_hir_id = tcx.hir().local_def_id_to_hir_id(trait_def_id.expect_local());
|
|
|
|
let item = match tcx.hir().get(trait_hir_id) {
|
|
Node::Item(item) => item,
|
|
_ => bug!("trait_node_id {} is not an item", trait_hir_id),
|
|
};
|
|
|
|
let (generics, bounds) = match item.kind {
|
|
hir::ItemKind::Trait(.., ref generics, ref supertraits, _) => (generics, supertraits),
|
|
hir::ItemKind::TraitAlias(ref generics, ref supertraits) => (generics, supertraits),
|
|
_ => span_bug!(item.span, "super_predicates invoked on non-trait"),
|
|
};
|
|
|
|
let icx = ItemCtxt::new(tcx, trait_def_id);
|
|
|
|
// Convert the bounds that follow the colon, e.g., `Bar + Zed` in `trait Foo: Bar + Zed`.
|
|
let self_param_ty = tcx.types.self_param;
|
|
let superbounds1 =
|
|
AstConv::compute_bounds(&icx, self_param_ty, bounds, SizedByDefault::No, item.span);
|
|
|
|
let superbounds1 = superbounds1.predicates(tcx, self_param_ty);
|
|
|
|
// Convert any explicit superbounds in the where-clause,
|
|
// e.g., `trait Foo where Self: Bar`.
|
|
// In the case of trait aliases, however, we include all bounds in the where-clause,
|
|
// so e.g., `trait Foo = where u32: PartialEq<Self>` would include `u32: PartialEq<Self>`
|
|
// as one of its "superpredicates".
|
|
let is_trait_alias = tcx.is_trait_alias(trait_def_id);
|
|
let superbounds2 = icx.type_parameter_bounds_in_generics(
|
|
generics,
|
|
item.hir_id,
|
|
self_param_ty,
|
|
OnlySelfBounds(!is_trait_alias),
|
|
);
|
|
|
|
// Combine the two lists to form the complete set of superbounds:
|
|
let superbounds = &*tcx.arena.alloc_from_iter(superbounds1.into_iter().chain(superbounds2));
|
|
|
|
// Now require that immediate supertraits are converted,
|
|
// which will, in turn, reach indirect supertraits.
|
|
for &(pred, span) in superbounds {
|
|
debug!("superbound: {:?}", pred);
|
|
if let ty::PredicateAtom::Trait(bound, _) = pred.skip_binders() {
|
|
tcx.at(span).super_predicates_of(bound.def_id());
|
|
}
|
|
}
|
|
|
|
ty::GenericPredicates { parent: None, predicates: superbounds }
|
|
}
|
|
|
|
fn trait_def(tcx: TyCtxt<'_>, def_id: DefId) -> ty::TraitDef {
|
|
let hir_id = tcx.hir().local_def_id_to_hir_id(def_id.expect_local());
|
|
let item = tcx.hir().expect_item(hir_id);
|
|
|
|
let (is_auto, unsafety) = match item.kind {
|
|
hir::ItemKind::Trait(is_auto, unsafety, ..) => (is_auto == hir::IsAuto::Yes, unsafety),
|
|
hir::ItemKind::TraitAlias(..) => (false, hir::Unsafety::Normal),
|
|
_ => span_bug!(item.span, "trait_def_of_item invoked on non-trait"),
|
|
};
|
|
|
|
let paren_sugar = tcx.has_attr(def_id, sym::rustc_paren_sugar);
|
|
if paren_sugar && !tcx.features().unboxed_closures {
|
|
tcx.sess
|
|
.struct_span_err(
|
|
item.span,
|
|
"the `#[rustc_paren_sugar]` attribute is a temporary means of controlling \
|
|
which traits can use parenthetical notation",
|
|
)
|
|
.help("add `#![feature(unboxed_closures)]` to the crate attributes to use it")
|
|
.emit();
|
|
}
|
|
|
|
let is_marker = tcx.has_attr(def_id, sym::marker);
|
|
let spec_kind = if tcx.has_attr(def_id, sym::rustc_unsafe_specialization_marker) {
|
|
ty::trait_def::TraitSpecializationKind::Marker
|
|
} else if tcx.has_attr(def_id, sym::rustc_specialization_trait) {
|
|
ty::trait_def::TraitSpecializationKind::AlwaysApplicable
|
|
} else {
|
|
ty::trait_def::TraitSpecializationKind::None
|
|
};
|
|
let def_path_hash = tcx.def_path_hash(def_id);
|
|
ty::TraitDef::new(def_id, unsafety, paren_sugar, is_auto, is_marker, spec_kind, def_path_hash)
|
|
}
|
|
|
|
fn has_late_bound_regions<'tcx>(tcx: TyCtxt<'tcx>, node: Node<'tcx>) -> Option<Span> {
|
|
struct LateBoundRegionsDetector<'tcx> {
|
|
tcx: TyCtxt<'tcx>,
|
|
outer_index: ty::DebruijnIndex,
|
|
has_late_bound_regions: Option<Span>,
|
|
}
|
|
|
|
impl Visitor<'tcx> for LateBoundRegionsDetector<'tcx> {
|
|
type Map = intravisit::ErasedMap<'tcx>;
|
|
|
|
fn nested_visit_map(&mut self) -> NestedVisitorMap<Self::Map> {
|
|
NestedVisitorMap::None
|
|
}
|
|
|
|
fn visit_ty(&mut self, ty: &'tcx hir::Ty<'tcx>) {
|
|
if self.has_late_bound_regions.is_some() {
|
|
return;
|
|
}
|
|
match ty.kind {
|
|
hir::TyKind::BareFn(..) => {
|
|
self.outer_index.shift_in(1);
|
|
intravisit::walk_ty(self, ty);
|
|
self.outer_index.shift_out(1);
|
|
}
|
|
_ => intravisit::walk_ty(self, ty),
|
|
}
|
|
}
|
|
|
|
fn visit_poly_trait_ref(
|
|
&mut self,
|
|
tr: &'tcx hir::PolyTraitRef<'tcx>,
|
|
m: hir::TraitBoundModifier,
|
|
) {
|
|
if self.has_late_bound_regions.is_some() {
|
|
return;
|
|
}
|
|
self.outer_index.shift_in(1);
|
|
intravisit::walk_poly_trait_ref(self, tr, m);
|
|
self.outer_index.shift_out(1);
|
|
}
|
|
|
|
fn visit_lifetime(&mut self, lt: &'tcx hir::Lifetime) {
|
|
if self.has_late_bound_regions.is_some() {
|
|
return;
|
|
}
|
|
|
|
match self.tcx.named_region(lt.hir_id) {
|
|
Some(rl::Region::Static | rl::Region::EarlyBound(..)) => {}
|
|
Some(
|
|
rl::Region::LateBound(debruijn, _, _) | rl::Region::LateBoundAnon(debruijn, _),
|
|
) if debruijn < self.outer_index => {}
|
|
Some(
|
|
rl::Region::LateBound(..)
|
|
| rl::Region::LateBoundAnon(..)
|
|
| rl::Region::Free(..),
|
|
)
|
|
| None => {
|
|
self.has_late_bound_regions = Some(lt.span);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
fn has_late_bound_regions<'tcx>(
|
|
tcx: TyCtxt<'tcx>,
|
|
generics: &'tcx hir::Generics<'tcx>,
|
|
decl: &'tcx hir::FnDecl<'tcx>,
|
|
) -> Option<Span> {
|
|
let mut visitor = LateBoundRegionsDetector {
|
|
tcx,
|
|
outer_index: ty::INNERMOST,
|
|
has_late_bound_regions: None,
|
|
};
|
|
for param in generics.params {
|
|
if let GenericParamKind::Lifetime { .. } = param.kind {
|
|
if tcx.is_late_bound(param.hir_id) {
|
|
return Some(param.span);
|
|
}
|
|
}
|
|
}
|
|
visitor.visit_fn_decl(decl);
|
|
visitor.has_late_bound_regions
|
|
}
|
|
|
|
match node {
|
|
Node::TraitItem(item) => match item.kind {
|
|
hir::TraitItemKind::Fn(ref sig, _) => {
|
|
has_late_bound_regions(tcx, &item.generics, &sig.decl)
|
|
}
|
|
_ => None,
|
|
},
|
|
Node::ImplItem(item) => match item.kind {
|
|
hir::ImplItemKind::Fn(ref sig, _) => {
|
|
has_late_bound_regions(tcx, &item.generics, &sig.decl)
|
|
}
|
|
_ => None,
|
|
},
|
|
Node::ForeignItem(item) => match item.kind {
|
|
hir::ForeignItemKind::Fn(ref fn_decl, _, ref generics) => {
|
|
has_late_bound_regions(tcx, generics, fn_decl)
|
|
}
|
|
_ => None,
|
|
},
|
|
Node::Item(item) => match item.kind {
|
|
hir::ItemKind::Fn(ref sig, .., ref generics, _) => {
|
|
has_late_bound_regions(tcx, generics, &sig.decl)
|
|
}
|
|
_ => None,
|
|
},
|
|
_ => None,
|
|
}
|
|
}
|
|
|
|
struct AnonConstInParamListDetector {
|
|
in_param_list: bool,
|
|
found_anon_const_in_list: bool,
|
|
ct: HirId,
|
|
}
|
|
|
|
impl<'v> Visitor<'v> for AnonConstInParamListDetector {
|
|
type Map = intravisit::ErasedMap<'v>;
|
|
|
|
fn nested_visit_map(&mut self) -> NestedVisitorMap<Self::Map> {
|
|
NestedVisitorMap::None
|
|
}
|
|
|
|
fn visit_generic_param(&mut self, p: &'v hir::GenericParam<'v>) {
|
|
let prev = self.in_param_list;
|
|
self.in_param_list = true;
|
|
intravisit::walk_generic_param(self, p);
|
|
self.in_param_list = prev;
|
|
}
|
|
|
|
fn visit_anon_const(&mut self, c: &'v hir::AnonConst) {
|
|
if self.in_param_list && self.ct == c.hir_id {
|
|
self.found_anon_const_in_list = true;
|
|
} else {
|
|
intravisit::walk_anon_const(self, c)
|
|
}
|
|
}
|
|
}
|
|
|
|
fn generics_of(tcx: TyCtxt<'_>, def_id: DefId) -> ty::Generics {
|
|
use rustc_hir::*;
|
|
|
|
let hir_id = tcx.hir().local_def_id_to_hir_id(def_id.expect_local());
|
|
|
|
let node = tcx.hir().get(hir_id);
|
|
let parent_def_id = match node {
|
|
Node::ImplItem(_)
|
|
| Node::TraitItem(_)
|
|
| Node::Variant(_)
|
|
| Node::Ctor(..)
|
|
| Node::Field(_) => {
|
|
let parent_id = tcx.hir().get_parent_item(hir_id);
|
|
Some(tcx.hir().local_def_id(parent_id).to_def_id())
|
|
}
|
|
// FIXME(#43408) always enable this once `lazy_normalization` is
|
|
// stable enough and does not need a feature gate anymore.
|
|
Node::AnonConst(_) => {
|
|
let parent_id = tcx.hir().get_parent_item(hir_id);
|
|
let parent_def_id = tcx.hir().local_def_id(parent_id);
|
|
|
|
let mut in_param_list = false;
|
|
for (_parent, node) in tcx.hir().parent_iter(hir_id) {
|
|
if let Some(generics) = node.generics() {
|
|
let mut visitor = AnonConstInParamListDetector {
|
|
in_param_list: false,
|
|
found_anon_const_in_list: false,
|
|
ct: hir_id,
|
|
};
|
|
|
|
visitor.visit_generics(generics);
|
|
in_param_list = visitor.found_anon_const_in_list;
|
|
break;
|
|
}
|
|
}
|
|
|
|
if in_param_list {
|
|
// We do not allow generic parameters in anon consts if we are inside
|
|
// of a param list.
|
|
//
|
|
// This affects both default type bindings, e.g. `struct<T, U = [u8; std::mem::size_of::<T>()]>(T, U)`,
|
|
// and the types of const parameters, e.g. `struct V<const N: usize, const M: [u8; N]>();`.
|
|
None
|
|
} else if tcx.lazy_normalization() {
|
|
// HACK(eddyb) this provides the correct generics when
|
|
// `feature(const_generics)` is enabled, so that const expressions
|
|
// used with const generics, e.g. `Foo<{N+1}>`, can work at all.
|
|
//
|
|
// Note that we do not supply the parent generics when using
|
|
// `min_const_generics`.
|
|
Some(parent_def_id.to_def_id())
|
|
} else {
|
|
let parent_node = tcx.hir().get(tcx.hir().get_parent_node(hir_id));
|
|
match parent_node {
|
|
// HACK(eddyb) this provides the correct generics for repeat
|
|
// expressions' count (i.e. `N` in `[x; N]`), and explicit
|
|
// `enum` discriminants (i.e. `D` in `enum Foo { Bar = D }`),
|
|
// as they shouldn't be able to cause query cycle errors.
|
|
Node::Expr(&Expr { kind: ExprKind::Repeat(_, ref constant), .. })
|
|
| Node::Variant(Variant { disr_expr: Some(ref constant), .. })
|
|
if constant.hir_id == hir_id =>
|
|
{
|
|
Some(parent_def_id.to_def_id())
|
|
}
|
|
|
|
_ => None,
|
|
}
|
|
}
|
|
}
|
|
Node::Expr(&hir::Expr { kind: hir::ExprKind::Closure(..), .. }) => {
|
|
Some(tcx.closure_base_def_id(def_id))
|
|
}
|
|
Node::Item(item) => match item.kind {
|
|
ItemKind::OpaqueTy(hir::OpaqueTy { impl_trait_fn, .. }) => {
|
|
impl_trait_fn.or_else(|| {
|
|
let parent_id = tcx.hir().get_parent_item(hir_id);
|
|
assert!(parent_id != hir_id && parent_id != CRATE_HIR_ID);
|
|
debug!("generics_of: parent of opaque ty {:?} is {:?}", def_id, parent_id);
|
|
// Opaque types are always nested within another item, and
|
|
// inherit the generics of the item.
|
|
Some(tcx.hir().local_def_id(parent_id).to_def_id())
|
|
})
|
|
}
|
|
_ => None,
|
|
},
|
|
_ => None,
|
|
};
|
|
|
|
let mut opt_self = None;
|
|
let mut allow_defaults = false;
|
|
|
|
let no_generics = hir::Generics::empty();
|
|
let ast_generics = match node {
|
|
Node::TraitItem(item) => &item.generics,
|
|
|
|
Node::ImplItem(item) => &item.generics,
|
|
|
|
Node::Item(item) => {
|
|
match item.kind {
|
|
ItemKind::Fn(.., ref generics, _) | ItemKind::Impl { ref generics, .. } => generics,
|
|
|
|
ItemKind::TyAlias(_, ref generics)
|
|
| ItemKind::Enum(_, ref generics)
|
|
| ItemKind::Struct(_, ref generics)
|
|
| ItemKind::OpaqueTy(hir::OpaqueTy { ref generics, .. })
|
|
| ItemKind::Union(_, ref generics) => {
|
|
allow_defaults = true;
|
|
generics
|
|
}
|
|
|
|
ItemKind::Trait(_, _, ref generics, ..)
|
|
| ItemKind::TraitAlias(ref generics, ..) => {
|
|
// Add in the self type parameter.
|
|
//
|
|
// Something of a hack: use the node id for the trait, also as
|
|
// the node id for the Self type parameter.
|
|
let param_id = item.hir_id;
|
|
|
|
opt_self = Some(ty::GenericParamDef {
|
|
index: 0,
|
|
name: kw::SelfUpper,
|
|
def_id: tcx.hir().local_def_id(param_id).to_def_id(),
|
|
pure_wrt_drop: false,
|
|
kind: ty::GenericParamDefKind::Type {
|
|
has_default: false,
|
|
object_lifetime_default: rl::Set1::Empty,
|
|
synthetic: None,
|
|
},
|
|
});
|
|
|
|
allow_defaults = true;
|
|
generics
|
|
}
|
|
|
|
_ => &no_generics,
|
|
}
|
|
}
|
|
|
|
Node::ForeignItem(item) => match item.kind {
|
|
ForeignItemKind::Static(..) => &no_generics,
|
|
ForeignItemKind::Fn(_, _, ref generics) => generics,
|
|
ForeignItemKind::Type => &no_generics,
|
|
},
|
|
|
|
_ => &no_generics,
|
|
};
|
|
|
|
let has_self = opt_self.is_some();
|
|
let mut parent_has_self = false;
|
|
let mut own_start = has_self as u32;
|
|
let parent_count = parent_def_id.map_or(0, |def_id| {
|
|
let generics = tcx.generics_of(def_id);
|
|
assert_eq!(has_self, false);
|
|
parent_has_self = generics.has_self;
|
|
own_start = generics.count() as u32;
|
|
generics.parent_count + generics.params.len()
|
|
});
|
|
|
|
let mut params: Vec<_> = Vec::with_capacity(ast_generics.params.len() + has_self as usize);
|
|
|
|
if let Some(opt_self) = opt_self {
|
|
params.push(opt_self);
|
|
}
|
|
|
|
let early_lifetimes = early_bound_lifetimes_from_generics(tcx, ast_generics);
|
|
params.extend(early_lifetimes.enumerate().map(|(i, param)| ty::GenericParamDef {
|
|
name: param.name.ident().name,
|
|
index: own_start + i as u32,
|
|
def_id: tcx.hir().local_def_id(param.hir_id).to_def_id(),
|
|
pure_wrt_drop: param.pure_wrt_drop,
|
|
kind: ty::GenericParamDefKind::Lifetime,
|
|
}));
|
|
|
|
let object_lifetime_defaults = tcx.object_lifetime_defaults(hir_id);
|
|
|
|
// Now create the real type and const parameters.
|
|
let type_start = own_start - has_self as u32 + params.len() as u32;
|
|
let mut i = 0;
|
|
|
|
params.extend(ast_generics.params.iter().filter_map(|param| match param.kind {
|
|
GenericParamKind::Lifetime { .. } => None,
|
|
GenericParamKind::Type { ref default, synthetic, .. } => {
|
|
if !allow_defaults && default.is_some() {
|
|
if !tcx.features().default_type_parameter_fallback {
|
|
tcx.struct_span_lint_hir(
|
|
lint::builtin::INVALID_TYPE_PARAM_DEFAULT,
|
|
param.hir_id,
|
|
param.span,
|
|
|lint| {
|
|
lint.build(
|
|
"defaults for type parameters are only allowed in \
|
|
`struct`, `enum`, `type`, or `trait` definitions.",
|
|
)
|
|
.emit();
|
|
},
|
|
);
|
|
}
|
|
}
|
|
|
|
let kind = ty::GenericParamDefKind::Type {
|
|
has_default: default.is_some(),
|
|
object_lifetime_default: object_lifetime_defaults
|
|
.as_ref()
|
|
.map_or(rl::Set1::Empty, |o| o[i]),
|
|
synthetic,
|
|
};
|
|
|
|
let param_def = ty::GenericParamDef {
|
|
index: type_start + i as u32,
|
|
name: param.name.ident().name,
|
|
def_id: tcx.hir().local_def_id(param.hir_id).to_def_id(),
|
|
pure_wrt_drop: param.pure_wrt_drop,
|
|
kind,
|
|
};
|
|
i += 1;
|
|
Some(param_def)
|
|
}
|
|
GenericParamKind::Const { .. } => {
|
|
let param_def = ty::GenericParamDef {
|
|
index: type_start + i as u32,
|
|
name: param.name.ident().name,
|
|
def_id: tcx.hir().local_def_id(param.hir_id).to_def_id(),
|
|
pure_wrt_drop: param.pure_wrt_drop,
|
|
kind: ty::GenericParamDefKind::Const,
|
|
};
|
|
i += 1;
|
|
Some(param_def)
|
|
}
|
|
}));
|
|
|
|
// provide junk type parameter defs - the only place that
|
|
// cares about anything but the length is instantiation,
|
|
// and we don't do that for closures.
|
|
if let Node::Expr(&hir::Expr { kind: hir::ExprKind::Closure(.., gen), .. }) = node {
|
|
let dummy_args = if gen.is_some() {
|
|
&["<resume_ty>", "<yield_ty>", "<return_ty>", "<witness>", "<upvars>"][..]
|
|
} else {
|
|
&["<closure_kind>", "<closure_signature>", "<upvars>"][..]
|
|
};
|
|
|
|
params.extend(dummy_args.iter().enumerate().map(|(i, &arg)| ty::GenericParamDef {
|
|
index: type_start + i as u32,
|
|
name: Symbol::intern(arg),
|
|
def_id,
|
|
pure_wrt_drop: false,
|
|
kind: ty::GenericParamDefKind::Type {
|
|
has_default: false,
|
|
object_lifetime_default: rl::Set1::Empty,
|
|
synthetic: None,
|
|
},
|
|
}));
|
|
}
|
|
|
|
let param_def_id_to_index = params.iter().map(|param| (param.def_id, param.index)).collect();
|
|
|
|
ty::Generics {
|
|
parent: parent_def_id,
|
|
parent_count,
|
|
params,
|
|
param_def_id_to_index,
|
|
has_self: has_self || parent_has_self,
|
|
has_late_bound_regions: has_late_bound_regions(tcx, node),
|
|
}
|
|
}
|
|
|
|
fn are_suggestable_generic_args(generic_args: &[hir::GenericArg<'_>]) -> bool {
|
|
generic_args
|
|
.iter()
|
|
.filter_map(|arg| match arg {
|
|
hir::GenericArg::Type(ty) => Some(ty),
|
|
_ => None,
|
|
})
|
|
.any(is_suggestable_infer_ty)
|
|
}
|
|
|
|
/// Whether `ty` is a type with `_` placeholders that can be inferred. Used in diagnostics only to
|
|
/// use inference to provide suggestions for the appropriate type if possible.
|
|
fn is_suggestable_infer_ty(ty: &hir::Ty<'_>) -> bool {
|
|
use hir::TyKind::*;
|
|
match &ty.kind {
|
|
Infer => true,
|
|
Slice(ty) | Array(ty, _) => is_suggestable_infer_ty(ty),
|
|
Tup(tys) => tys.iter().any(is_suggestable_infer_ty),
|
|
Ptr(mut_ty) | Rptr(_, mut_ty) => is_suggestable_infer_ty(mut_ty.ty),
|
|
OpaqueDef(_, generic_args) => are_suggestable_generic_args(generic_args),
|
|
Path(hir::QPath::TypeRelative(ty, segment)) => {
|
|
is_suggestable_infer_ty(ty) || are_suggestable_generic_args(segment.generic_args().args)
|
|
}
|
|
Path(hir::QPath::Resolved(ty_opt, hir::Path { segments, .. })) => {
|
|
ty_opt.map_or(false, is_suggestable_infer_ty)
|
|
|| segments
|
|
.iter()
|
|
.any(|segment| are_suggestable_generic_args(segment.generic_args().args))
|
|
}
|
|
_ => false,
|
|
}
|
|
}
|
|
|
|
pub fn get_infer_ret_ty(output: &'hir hir::FnRetTy<'hir>) -> Option<&'hir hir::Ty<'hir>> {
|
|
if let hir::FnRetTy::Return(ref ty) = output {
|
|
if is_suggestable_infer_ty(ty) {
|
|
return Some(&**ty);
|
|
}
|
|
}
|
|
None
|
|
}
|
|
|
|
fn fn_sig(tcx: TyCtxt<'_>, def_id: DefId) -> ty::PolyFnSig<'_> {
|
|
use rustc_hir::Node::*;
|
|
use rustc_hir::*;
|
|
|
|
let def_id = def_id.expect_local();
|
|
let hir_id = tcx.hir().local_def_id_to_hir_id(def_id);
|
|
|
|
let icx = ItemCtxt::new(tcx, def_id.to_def_id());
|
|
|
|
match tcx.hir().get(hir_id) {
|
|
TraitItem(hir::TraitItem {
|
|
kind: TraitItemKind::Fn(sig, TraitFn::Provided(_)),
|
|
ident,
|
|
generics,
|
|
..
|
|
})
|
|
| ImplItem(hir::ImplItem { kind: ImplItemKind::Fn(sig, _), ident, generics, .. })
|
|
| Item(hir::Item { kind: ItemKind::Fn(sig, generics, _), ident, .. }) => {
|
|
match get_infer_ret_ty(&sig.decl.output) {
|
|
Some(ty) => {
|
|
let fn_sig = tcx.typeck(def_id).liberated_fn_sigs()[hir_id];
|
|
let mut visitor = PlaceholderHirTyCollector::default();
|
|
visitor.visit_ty(ty);
|
|
let mut diag = bad_placeholder_type(tcx, visitor.0);
|
|
let ret_ty = fn_sig.output();
|
|
if ret_ty != tcx.ty_error() {
|
|
if !ret_ty.is_closure() {
|
|
let ret_ty_str = match ret_ty.kind() {
|
|
// Suggest a function pointer return type instead of a unique function definition
|
|
// (e.g. `fn() -> i32` instead of `fn() -> i32 { f }`, the latter of which is invalid
|
|
// syntax)
|
|
ty::FnDef(..) => ret_ty.fn_sig(tcx).to_string(),
|
|
_ => ret_ty.to_string(),
|
|
};
|
|
diag.span_suggestion(
|
|
ty.span,
|
|
"replace with the correct return type",
|
|
ret_ty_str,
|
|
Applicability::MaybeIncorrect,
|
|
);
|
|
} else {
|
|
// We're dealing with a closure, so we should suggest using `impl Fn` or trait bounds
|
|
// to prevent the user from getting a papercut while trying to use the unique closure
|
|
// syntax (e.g. `[closure@src/lib.rs:2:5: 2:9]`).
|
|
diag.help("consider using an `Fn`, `FnMut`, or `FnOnce` trait bound");
|
|
diag.note("for more information on `Fn` traits and closure types, see https://doc.rust-lang.org/book/ch13-01-closures.html");
|
|
}
|
|
}
|
|
diag.emit();
|
|
ty::Binder::bind(fn_sig)
|
|
}
|
|
None => AstConv::ty_of_fn(
|
|
&icx,
|
|
sig.header.unsafety,
|
|
sig.header.abi,
|
|
&sig.decl,
|
|
&generics,
|
|
Some(ident.span),
|
|
),
|
|
}
|
|
}
|
|
|
|
TraitItem(hir::TraitItem {
|
|
kind: TraitItemKind::Fn(FnSig { header, decl, span: _ }, _),
|
|
ident,
|
|
generics,
|
|
..
|
|
}) => {
|
|
AstConv::ty_of_fn(&icx, header.unsafety, header.abi, decl, &generics, Some(ident.span))
|
|
}
|
|
|
|
ForeignItem(&hir::ForeignItem {
|
|
kind: ForeignItemKind::Fn(ref fn_decl, _, _),
|
|
ident,
|
|
..
|
|
}) => {
|
|
let abi = tcx.hir().get_foreign_abi(hir_id);
|
|
compute_sig_of_foreign_fn_decl(tcx, def_id.to_def_id(), fn_decl, abi, ident)
|
|
}
|
|
|
|
Ctor(data) | Variant(hir::Variant { data, .. }) if data.ctor_hir_id().is_some() => {
|
|
let ty = tcx.type_of(tcx.hir().get_parent_did(hir_id).to_def_id());
|
|
let inputs =
|
|
data.fields().iter().map(|f| tcx.type_of(tcx.hir().local_def_id(f.hir_id)));
|
|
ty::Binder::bind(tcx.mk_fn_sig(
|
|
inputs,
|
|
ty,
|
|
false,
|
|
hir::Unsafety::Normal,
|
|
abi::Abi::Rust,
|
|
))
|
|
}
|
|
|
|
Expr(&hir::Expr { kind: hir::ExprKind::Closure(..), .. }) => {
|
|
// Closure signatures are not like other function
|
|
// signatures and cannot be accessed through `fn_sig`. For
|
|
// example, a closure signature excludes the `self`
|
|
// argument. In any case they are embedded within the
|
|
// closure type as part of the `ClosureSubsts`.
|
|
//
|
|
// To get the signature of a closure, you should use the
|
|
// `sig` method on the `ClosureSubsts`:
|
|
//
|
|
// substs.as_closure().sig(def_id, tcx)
|
|
bug!(
|
|
"to get the signature of a closure, use `substs.as_closure().sig()` not `fn_sig()`",
|
|
);
|
|
}
|
|
|
|
x => {
|
|
bug!("unexpected sort of node in fn_sig(): {:?}", x);
|
|
}
|
|
}
|
|
}
|
|
|
|
fn impl_trait_ref(tcx: TyCtxt<'_>, def_id: DefId) -> Option<ty::TraitRef<'_>> {
|
|
let icx = ItemCtxt::new(tcx, def_id);
|
|
|
|
let hir_id = tcx.hir().local_def_id_to_hir_id(def_id.expect_local());
|
|
match tcx.hir().expect_item(hir_id).kind {
|
|
hir::ItemKind::Impl { ref of_trait, .. } => of_trait.as_ref().map(|ast_trait_ref| {
|
|
let selfty = tcx.type_of(def_id);
|
|
AstConv::instantiate_mono_trait_ref(&icx, ast_trait_ref, selfty)
|
|
}),
|
|
_ => bug!(),
|
|
}
|
|
}
|
|
|
|
fn impl_polarity(tcx: TyCtxt<'_>, def_id: DefId) -> ty::ImplPolarity {
|
|
let hir_id = tcx.hir().local_def_id_to_hir_id(def_id.expect_local());
|
|
let is_rustc_reservation = tcx.has_attr(def_id, sym::rustc_reservation_impl);
|
|
let item = tcx.hir().expect_item(hir_id);
|
|
match &item.kind {
|
|
hir::ItemKind::Impl { polarity: hir::ImplPolarity::Negative(span), of_trait, .. } => {
|
|
if is_rustc_reservation {
|
|
let span = span.to(of_trait.as_ref().map(|t| t.path.span).unwrap_or(*span));
|
|
tcx.sess.span_err(span, "reservation impls can't be negative");
|
|
}
|
|
ty::ImplPolarity::Negative
|
|
}
|
|
hir::ItemKind::Impl { polarity: hir::ImplPolarity::Positive, of_trait: None, .. } => {
|
|
if is_rustc_reservation {
|
|
tcx.sess.span_err(item.span, "reservation impls can't be inherent");
|
|
}
|
|
ty::ImplPolarity::Positive
|
|
}
|
|
hir::ItemKind::Impl {
|
|
polarity: hir::ImplPolarity::Positive, of_trait: Some(_), ..
|
|
} => {
|
|
if is_rustc_reservation {
|
|
ty::ImplPolarity::Reservation
|
|
} else {
|
|
ty::ImplPolarity::Positive
|
|
}
|
|
}
|
|
ref item => bug!("impl_polarity: {:?} not an impl", item),
|
|
}
|
|
}
|
|
|
|
/// Returns the early-bound lifetimes declared in this generics
|
|
/// listing. For anything other than fns/methods, this is just all
|
|
/// the lifetimes that are declared. For fns or methods, we have to
|
|
/// screen out those that do not appear in any where-clauses etc using
|
|
/// `resolve_lifetime::early_bound_lifetimes`.
|
|
fn early_bound_lifetimes_from_generics<'a, 'tcx: 'a>(
|
|
tcx: TyCtxt<'tcx>,
|
|
generics: &'a hir::Generics<'a>,
|
|
) -> impl Iterator<Item = &'a hir::GenericParam<'a>> + Captures<'tcx> {
|
|
generics.params.iter().filter(move |param| match param.kind {
|
|
GenericParamKind::Lifetime { .. } => !tcx.is_late_bound(param.hir_id),
|
|
_ => false,
|
|
})
|
|
}
|
|
|
|
/// Returns a list of type predicates for the definition with ID `def_id`, including inferred
|
|
/// lifetime constraints. This includes all predicates returned by `explicit_predicates_of`, plus
|
|
/// inferred constraints concerning which regions outlive other regions.
|
|
fn predicates_defined_on(tcx: TyCtxt<'_>, def_id: DefId) -> ty::GenericPredicates<'_> {
|
|
debug!("predicates_defined_on({:?})", def_id);
|
|
let mut result = tcx.explicit_predicates_of(def_id);
|
|
debug!("predicates_defined_on: explicit_predicates_of({:?}) = {:?}", def_id, result,);
|
|
let inferred_outlives = tcx.inferred_outlives_of(def_id);
|
|
if !inferred_outlives.is_empty() {
|
|
debug!(
|
|
"predicates_defined_on: inferred_outlives_of({:?}) = {:?}",
|
|
def_id, inferred_outlives,
|
|
);
|
|
if result.predicates.is_empty() {
|
|
result.predicates = inferred_outlives;
|
|
} else {
|
|
result.predicates = tcx
|
|
.arena
|
|
.alloc_from_iter(result.predicates.iter().chain(inferred_outlives).copied());
|
|
}
|
|
}
|
|
|
|
debug!("predicates_defined_on({:?}) = {:?}", def_id, result);
|
|
result
|
|
}
|
|
|
|
/// Returns a list of all type predicates (explicit and implicit) for the definition with
|
|
/// ID `def_id`. This includes all predicates returned by `predicates_defined_on`, plus
|
|
/// `Self: Trait` predicates for traits.
|
|
fn predicates_of(tcx: TyCtxt<'_>, def_id: DefId) -> ty::GenericPredicates<'_> {
|
|
let mut result = tcx.predicates_defined_on(def_id);
|
|
|
|
if tcx.is_trait(def_id) {
|
|
// For traits, add `Self: Trait` predicate. This is
|
|
// not part of the predicates that a user writes, but it
|
|
// is something that one must prove in order to invoke a
|
|
// method or project an associated type.
|
|
//
|
|
// In the chalk setup, this predicate is not part of the
|
|
// "predicates" for a trait item. But it is useful in
|
|
// rustc because if you directly (e.g.) invoke a trait
|
|
// method like `Trait::method(...)`, you must naturally
|
|
// prove that the trait applies to the types that were
|
|
// used, and adding the predicate into this list ensures
|
|
// that this is done.
|
|
let span = tcx.sess.source_map().guess_head_span(tcx.def_span(def_id));
|
|
result.predicates =
|
|
tcx.arena.alloc_from_iter(result.predicates.iter().copied().chain(std::iter::once((
|
|
ty::TraitRef::identity(tcx, def_id).without_const().to_predicate(tcx),
|
|
span,
|
|
))));
|
|
}
|
|
debug!("predicates_of(def_id={:?}) = {:?}", def_id, result);
|
|
result
|
|
}
|
|
|
|
/// Returns a list of user-specified type predicates for the definition with ID `def_id`.
|
|
/// N.B., this does not include any implied/inferred constraints.
|
|
fn gather_explicit_predicates_of(tcx: TyCtxt<'_>, def_id: DefId) -> ty::GenericPredicates<'_> {
|
|
use rustc_hir::*;
|
|
|
|
debug!("explicit_predicates_of(def_id={:?})", def_id);
|
|
|
|
let hir_id = tcx.hir().local_def_id_to_hir_id(def_id.expect_local());
|
|
let node = tcx.hir().get(hir_id);
|
|
|
|
let mut is_trait = None;
|
|
let mut is_default_impl_trait = None;
|
|
|
|
let icx = ItemCtxt::new(tcx, def_id);
|
|
let constness = icx.default_constness_for_trait_bounds();
|
|
|
|
const NO_GENERICS: &hir::Generics<'_> = &hir::Generics::empty();
|
|
|
|
// We use an `IndexSet` to preserves order of insertion.
|
|
// Preserving the order of insertion is important here so as not to break UI tests.
|
|
let mut predicates: FxIndexSet<(ty::Predicate<'_>, Span)> = FxIndexSet::default();
|
|
|
|
let ast_generics = match node {
|
|
Node::TraitItem(item) => &item.generics,
|
|
|
|
Node::ImplItem(item) => &item.generics,
|
|
|
|
Node::Item(item) => {
|
|
match item.kind {
|
|
ItemKind::Impl { defaultness, ref generics, .. } => {
|
|
if defaultness.is_default() {
|
|
is_default_impl_trait = tcx.impl_trait_ref(def_id);
|
|
}
|
|
generics
|
|
}
|
|
ItemKind::Fn(.., ref generics, _)
|
|
| ItemKind::TyAlias(_, ref generics)
|
|
| ItemKind::Enum(_, ref generics)
|
|
| ItemKind::Struct(_, ref generics)
|
|
| ItemKind::Union(_, ref generics) => generics,
|
|
|
|
ItemKind::Trait(_, _, ref generics, ..) => {
|
|
is_trait = Some(ty::TraitRef::identity(tcx, def_id));
|
|
generics
|
|
}
|
|
ItemKind::TraitAlias(ref generics, _) => {
|
|
is_trait = Some(ty::TraitRef::identity(tcx, def_id));
|
|
generics
|
|
}
|
|
ItemKind::OpaqueTy(OpaqueTy {
|
|
bounds: _,
|
|
impl_trait_fn,
|
|
ref generics,
|
|
origin: _,
|
|
}) => {
|
|
if impl_trait_fn.is_some() {
|
|
// return-position impl trait
|
|
//
|
|
// We don't inherit predicates from the parent here:
|
|
// If we have, say `fn f<'a, T: 'a>() -> impl Sized {}`
|
|
// then the return type is `f::<'static, T>::{{opaque}}`.
|
|
//
|
|
// If we inherited the predicates of `f` then we would
|
|
// require that `T: 'static` to show that the return
|
|
// type is well-formed.
|
|
//
|
|
// The only way to have something with this opaque type
|
|
// is from the return type of the containing function,
|
|
// which will ensure that the function's predicates
|
|
// hold.
|
|
return ty::GenericPredicates { parent: None, predicates: &[] };
|
|
} else {
|
|
// type-alias impl trait
|
|
generics
|
|
}
|
|
}
|
|
|
|
_ => NO_GENERICS,
|
|
}
|
|
}
|
|
|
|
Node::ForeignItem(item) => match item.kind {
|
|
ForeignItemKind::Static(..) => NO_GENERICS,
|
|
ForeignItemKind::Fn(_, _, ref generics) => generics,
|
|
ForeignItemKind::Type => NO_GENERICS,
|
|
},
|
|
|
|
_ => NO_GENERICS,
|
|
};
|
|
|
|
let generics = tcx.generics_of(def_id);
|
|
let parent_count = generics.parent_count as u32;
|
|
let has_own_self = generics.has_self && parent_count == 0;
|
|
|
|
// Below we'll consider the bounds on the type parameters (including `Self`)
|
|
// and the explicit where-clauses, but to get the full set of predicates
|
|
// on a trait we need to add in the supertrait bounds and bounds found on
|
|
// associated types.
|
|
if let Some(_trait_ref) = is_trait {
|
|
predicates.extend(tcx.super_predicates_of(def_id).predicates.iter().cloned());
|
|
}
|
|
|
|
// In default impls, we can assume that the self type implements
|
|
// the trait. So in:
|
|
//
|
|
// default impl Foo for Bar { .. }
|
|
//
|
|
// we add a default where clause `Foo: Bar`. We do a similar thing for traits
|
|
// (see below). Recall that a default impl is not itself an impl, but rather a
|
|
// set of defaults that can be incorporated into another impl.
|
|
if let Some(trait_ref) = is_default_impl_trait {
|
|
predicates.insert((
|
|
trait_ref.to_poly_trait_ref().without_const().to_predicate(tcx),
|
|
tcx.def_span(def_id),
|
|
));
|
|
}
|
|
|
|
// Collect the region predicates that were declared inline as
|
|
// well. In the case of parameters declared on a fn or method, we
|
|
// have to be careful to only iterate over early-bound regions.
|
|
let mut index = parent_count + has_own_self as u32;
|
|
for param in early_bound_lifetimes_from_generics(tcx, ast_generics) {
|
|
let region = tcx.mk_region(ty::ReEarlyBound(ty::EarlyBoundRegion {
|
|
def_id: tcx.hir().local_def_id(param.hir_id).to_def_id(),
|
|
index,
|
|
name: param.name.ident().name,
|
|
}));
|
|
index += 1;
|
|
|
|
match param.kind {
|
|
GenericParamKind::Lifetime { .. } => {
|
|
param.bounds.iter().for_each(|bound| match bound {
|
|
hir::GenericBound::Outlives(lt) => {
|
|
let bound = AstConv::ast_region_to_region(&icx, <, None);
|
|
let outlives = ty::Binder::bind(ty::OutlivesPredicate(region, bound));
|
|
predicates.insert((outlives.to_predicate(tcx), lt.span));
|
|
}
|
|
_ => bug!(),
|
|
});
|
|
}
|
|
_ => bug!(),
|
|
}
|
|
}
|
|
|
|
// Collect the predicates that were written inline by the user on each
|
|
// type parameter (e.g., `<T: Foo>`).
|
|
for param in ast_generics.params {
|
|
match param.kind {
|
|
// We already dealt with early bound lifetimes above.
|
|
GenericParamKind::Lifetime { .. } => (),
|
|
GenericParamKind::Type { .. } => {
|
|
let name = param.name.ident().name;
|
|
let param_ty = ty::ParamTy::new(index, name).to_ty(tcx);
|
|
index += 1;
|
|
|
|
let sized = SizedByDefault::Yes;
|
|
let bounds =
|
|
AstConv::compute_bounds(&icx, param_ty, ¶m.bounds, sized, param.span);
|
|
predicates.extend(bounds.predicates(tcx, param_ty));
|
|
}
|
|
GenericParamKind::Const { .. } => {
|
|
// Bounds on const parameters are currently not possible.
|
|
debug_assert!(param.bounds.is_empty());
|
|
index += 1;
|
|
}
|
|
}
|
|
}
|
|
|
|
// Add in the bounds that appear in the where-clause.
|
|
let where_clause = &ast_generics.where_clause;
|
|
for predicate in where_clause.predicates {
|
|
match predicate {
|
|
&hir::WherePredicate::BoundPredicate(ref bound_pred) => {
|
|
let ty = icx.to_ty(&bound_pred.bounded_ty);
|
|
|
|
// Keep the type around in a dummy predicate, in case of no bounds.
|
|
// That way, `where Ty:` is not a complete noop (see #53696) and `Ty`
|
|
// is still checked for WF.
|
|
if bound_pred.bounds.is_empty() {
|
|
if let ty::Param(_) = ty.kind() {
|
|
// This is a `where T:`, which can be in the HIR from the
|
|
// transformation that moves `?Sized` to `T`'s declaration.
|
|
// We can skip the predicate because type parameters are
|
|
// trivially WF, but also we *should*, to avoid exposing
|
|
// users who never wrote `where Type:,` themselves, to
|
|
// compiler/tooling bugs from not handling WF predicates.
|
|
} else {
|
|
let span = bound_pred.bounded_ty.span;
|
|
let re_root_empty = tcx.lifetimes.re_root_empty;
|
|
let predicate = ty::Binder::bind(ty::PredicateAtom::TypeOutlives(
|
|
ty::OutlivesPredicate(ty, re_root_empty),
|
|
));
|
|
predicates.insert((
|
|
predicate.potentially_quantified(tcx, ty::PredicateKind::ForAll),
|
|
span,
|
|
));
|
|
}
|
|
}
|
|
|
|
for bound in bound_pred.bounds.iter() {
|
|
match bound {
|
|
&hir::GenericBound::Trait(ref poly_trait_ref, modifier) => {
|
|
let constness = match modifier {
|
|
hir::TraitBoundModifier::MaybeConst => hir::Constness::NotConst,
|
|
hir::TraitBoundModifier::None => constness,
|
|
hir::TraitBoundModifier::Maybe => bug!("this wasn't handled"),
|
|
};
|
|
|
|
let mut bounds = Bounds::default();
|
|
let _ = AstConv::instantiate_poly_trait_ref(
|
|
&icx,
|
|
poly_trait_ref,
|
|
constness,
|
|
ty,
|
|
&mut bounds,
|
|
);
|
|
predicates.extend(bounds.predicates(tcx, ty));
|
|
}
|
|
|
|
&hir::GenericBound::LangItemTrait(lang_item, span, hir_id, args) => {
|
|
let mut bounds = Bounds::default();
|
|
AstConv::instantiate_lang_item_trait_ref(
|
|
&icx,
|
|
lang_item,
|
|
span,
|
|
hir_id,
|
|
args,
|
|
ty,
|
|
&mut bounds,
|
|
);
|
|
predicates.extend(bounds.predicates(tcx, ty));
|
|
}
|
|
|
|
&hir::GenericBound::Outlives(ref lifetime) => {
|
|
let region = AstConv::ast_region_to_region(&icx, lifetime, None);
|
|
predicates.insert((
|
|
ty::Binder::bind(ty::PredicateAtom::TypeOutlives(
|
|
ty::OutlivesPredicate(ty, region),
|
|
))
|
|
.potentially_quantified(tcx, ty::PredicateKind::ForAll),
|
|
lifetime.span,
|
|
));
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
&hir::WherePredicate::RegionPredicate(ref region_pred) => {
|
|
let r1 = AstConv::ast_region_to_region(&icx, ®ion_pred.lifetime, None);
|
|
predicates.extend(region_pred.bounds.iter().map(|bound| {
|
|
let (r2, span) = match bound {
|
|
hir::GenericBound::Outlives(lt) => {
|
|
(AstConv::ast_region_to_region(&icx, lt, None), lt.span)
|
|
}
|
|
_ => bug!(),
|
|
};
|
|
let pred = ty::PredicateAtom::RegionOutlives(ty::OutlivesPredicate(r1, r2))
|
|
.to_predicate(icx.tcx);
|
|
|
|
(pred, span)
|
|
}))
|
|
}
|
|
|
|
&hir::WherePredicate::EqPredicate(..) => {
|
|
// FIXME(#20041)
|
|
}
|
|
}
|
|
}
|
|
|
|
if tcx.features().const_evaluatable_checked {
|
|
predicates.extend(const_evaluatable_predicates_of(tcx, def_id.expect_local()));
|
|
}
|
|
|
|
let mut predicates: Vec<_> = predicates.into_iter().collect();
|
|
|
|
// Subtle: before we store the predicates into the tcx, we
|
|
// sort them so that predicates like `T: Foo<Item=U>` come
|
|
// before uses of `U`. This avoids false ambiguity errors
|
|
// in trait checking. See `setup_constraining_predicates`
|
|
// for details.
|
|
if let Node::Item(&Item { kind: ItemKind::Impl { .. }, .. }) = node {
|
|
let self_ty = tcx.type_of(def_id);
|
|
let trait_ref = tcx.impl_trait_ref(def_id);
|
|
cgp::setup_constraining_predicates(
|
|
tcx,
|
|
&mut predicates,
|
|
trait_ref,
|
|
&mut cgp::parameters_for_impl(self_ty, trait_ref),
|
|
);
|
|
}
|
|
|
|
let result = ty::GenericPredicates {
|
|
parent: generics.parent,
|
|
predicates: tcx.arena.alloc_from_iter(predicates),
|
|
};
|
|
debug!("explicit_predicates_of(def_id={:?}) = {:?}", def_id, result);
|
|
result
|
|
}
|
|
|
|
fn const_evaluatable_predicates_of<'tcx>(
|
|
tcx: TyCtxt<'tcx>,
|
|
def_id: LocalDefId,
|
|
) -> FxIndexSet<(ty::Predicate<'tcx>, Span)> {
|
|
struct ConstCollector<'tcx> {
|
|
tcx: TyCtxt<'tcx>,
|
|
preds: FxIndexSet<(ty::Predicate<'tcx>, Span)>,
|
|
}
|
|
|
|
impl<'tcx> intravisit::Visitor<'tcx> for ConstCollector<'tcx> {
|
|
type Map = Map<'tcx>;
|
|
|
|
fn nested_visit_map(&mut self) -> intravisit::NestedVisitorMap<Self::Map> {
|
|
intravisit::NestedVisitorMap::None
|
|
}
|
|
|
|
fn visit_anon_const(&mut self, c: &'tcx hir::AnonConst) {
|
|
let def_id = self.tcx.hir().local_def_id(c.hir_id);
|
|
let ct = ty::Const::from_anon_const(self.tcx, def_id);
|
|
if let ty::ConstKind::Unevaluated(def, substs, None) = ct.val {
|
|
let span = self.tcx.hir().span(c.hir_id);
|
|
self.preds.insert((
|
|
ty::PredicateAtom::ConstEvaluatable(def, substs).to_predicate(self.tcx),
|
|
span,
|
|
));
|
|
}
|
|
}
|
|
|
|
// Look into `TyAlias`.
|
|
fn visit_ty(&mut self, ty: &'tcx hir::Ty<'tcx>) {
|
|
use ty::fold::{TypeFoldable, TypeVisitor};
|
|
struct TyAliasVisitor<'a, 'tcx> {
|
|
tcx: TyCtxt<'tcx>,
|
|
preds: &'a mut FxIndexSet<(ty::Predicate<'tcx>, Span)>,
|
|
span: Span,
|
|
}
|
|
|
|
impl<'a, 'tcx> TypeVisitor<'tcx> for TyAliasVisitor<'a, 'tcx> {
|
|
fn visit_const(&mut self, ct: &'tcx Const<'tcx>) -> ControlFlow<Self::BreakTy> {
|
|
if let ty::ConstKind::Unevaluated(def, substs, None) = ct.val {
|
|
self.preds.insert((
|
|
ty::PredicateAtom::ConstEvaluatable(def, substs).to_predicate(self.tcx),
|
|
self.span,
|
|
));
|
|
}
|
|
ControlFlow::CONTINUE
|
|
}
|
|
}
|
|
|
|
if let hir::TyKind::Path(hir::QPath::Resolved(None, path)) = ty.kind {
|
|
if let Res::Def(DefKind::TyAlias, def_id) = path.res {
|
|
let mut visitor =
|
|
TyAliasVisitor { tcx: self.tcx, preds: &mut self.preds, span: path.span };
|
|
self.tcx.type_of(def_id).visit_with(&mut visitor);
|
|
}
|
|
}
|
|
|
|
intravisit::walk_ty(self, ty)
|
|
}
|
|
}
|
|
|
|
let hir_id = tcx.hir().local_def_id_to_hir_id(def_id);
|
|
let node = tcx.hir().get(hir_id);
|
|
|
|
let mut collector = ConstCollector { tcx, preds: FxIndexSet::default() };
|
|
if let hir::Node::Item(item) = node {
|
|
if let hir::ItemKind::Impl { ref of_trait, ref self_ty, .. } = item.kind {
|
|
if let Some(of_trait) = of_trait {
|
|
debug!("const_evaluatable_predicates_of({:?}): visit impl trait_ref", def_id);
|
|
collector.visit_trait_ref(of_trait);
|
|
}
|
|
|
|
debug!("const_evaluatable_predicates_of({:?}): visit_self_ty", def_id);
|
|
collector.visit_ty(self_ty);
|
|
}
|
|
}
|
|
|
|
if let Some(generics) = node.generics() {
|
|
debug!("const_evaluatable_predicates_of({:?}): visit_generics", def_id);
|
|
collector.visit_generics(generics);
|
|
}
|
|
|
|
if let Some(fn_sig) = tcx.hir().fn_sig_by_hir_id(hir_id) {
|
|
debug!("const_evaluatable_predicates_of({:?}): visit_fn_decl", def_id);
|
|
collector.visit_fn_decl(fn_sig.decl);
|
|
}
|
|
debug!("const_evaluatable_predicates_of({:?}) = {:?}", def_id, collector.preds);
|
|
|
|
collector.preds
|
|
}
|
|
|
|
fn trait_explicit_predicates_and_bounds(
|
|
tcx: TyCtxt<'_>,
|
|
def_id: LocalDefId,
|
|
) -> ty::GenericPredicates<'_> {
|
|
assert_eq!(tcx.def_kind(def_id), DefKind::Trait);
|
|
gather_explicit_predicates_of(tcx, def_id.to_def_id())
|
|
}
|
|
|
|
fn explicit_predicates_of(tcx: TyCtxt<'_>, def_id: DefId) -> ty::GenericPredicates<'_> {
|
|
if let DefKind::Trait = tcx.def_kind(def_id) {
|
|
// Remove bounds on associated types from the predicates, they will be
|
|
// returned by `explicit_item_bounds`.
|
|
let predicates_and_bounds = tcx.trait_explicit_predicates_and_bounds(def_id.expect_local());
|
|
let trait_identity_substs = InternalSubsts::identity_for_item(tcx, def_id);
|
|
|
|
let is_assoc_item_ty = |ty: Ty<'_>| {
|
|
// For a predicate from a where clause to become a bound on an
|
|
// associated type:
|
|
// * It must use the identity substs of the item.
|
|
// * Since any generic parameters on the item are not in scope,
|
|
// this means that the item is not a GAT, and its identity
|
|
// substs are the same as the trait's.
|
|
// * It must be an associated type for this trait (*not* a
|
|
// supertrait).
|
|
if let ty::Projection(projection) = ty.kind() {
|
|
projection.substs == trait_identity_substs
|
|
&& tcx.associated_item(projection.item_def_id).container.id() == def_id
|
|
} else {
|
|
false
|
|
}
|
|
};
|
|
|
|
let predicates: Vec<_> = predicates_and_bounds
|
|
.predicates
|
|
.iter()
|
|
.copied()
|
|
.filter(|(pred, _)| match pred.skip_binders() {
|
|
ty::PredicateAtom::Trait(tr, _) => !is_assoc_item_ty(tr.self_ty()),
|
|
ty::PredicateAtom::Projection(proj) => {
|
|
!is_assoc_item_ty(proj.projection_ty.self_ty())
|
|
}
|
|
ty::PredicateAtom::TypeOutlives(outlives) => !is_assoc_item_ty(outlives.0),
|
|
_ => true,
|
|
})
|
|
.collect();
|
|
if predicates.len() == predicates_and_bounds.predicates.len() {
|
|
predicates_and_bounds
|
|
} else {
|
|
ty::GenericPredicates {
|
|
parent: predicates_and_bounds.parent,
|
|
predicates: tcx.arena.alloc_slice(&predicates),
|
|
}
|
|
}
|
|
} else {
|
|
gather_explicit_predicates_of(tcx, def_id)
|
|
}
|
|
}
|
|
|
|
fn projection_ty_from_predicates(
|
|
tcx: TyCtxt<'tcx>,
|
|
key: (
|
|
// ty_def_id
|
|
DefId,
|
|
// def_id of `N` in `<T as Trait>::N`
|
|
DefId,
|
|
),
|
|
) -> Option<ty::ProjectionTy<'tcx>> {
|
|
let (ty_def_id, item_def_id) = key;
|
|
let mut projection_ty = None;
|
|
for (predicate, _) in tcx.predicates_of(ty_def_id).predicates {
|
|
if let ty::PredicateAtom::Projection(projection_predicate) = predicate.skip_binders() {
|
|
if item_def_id == projection_predicate.projection_ty.item_def_id {
|
|
projection_ty = Some(projection_predicate.projection_ty);
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
projection_ty
|
|
}
|
|
|
|
/// Converts a specific `GenericBound` from the AST into a set of
|
|
/// predicates that apply to the self type. A vector is returned
|
|
/// because this can be anywhere from zero predicates (`T: ?Sized` adds no
|
|
/// predicates) to one (`T: Foo`) to many (`T: Bar<X = i32>` adds `T: Bar`
|
|
/// and `<T as Bar>::X == i32`).
|
|
fn predicates_from_bound<'tcx>(
|
|
astconv: &dyn AstConv<'tcx>,
|
|
param_ty: Ty<'tcx>,
|
|
bound: &'tcx hir::GenericBound<'tcx>,
|
|
constness: hir::Constness,
|
|
) -> Vec<(ty::Predicate<'tcx>, Span)> {
|
|
match *bound {
|
|
hir::GenericBound::Trait(ref tr, modifier) => {
|
|
let constness = match modifier {
|
|
hir::TraitBoundModifier::Maybe => return vec![],
|
|
hir::TraitBoundModifier::MaybeConst => hir::Constness::NotConst,
|
|
hir::TraitBoundModifier::None => constness,
|
|
};
|
|
|
|
let mut bounds = Bounds::default();
|
|
let _ = astconv.instantiate_poly_trait_ref(tr, constness, param_ty, &mut bounds);
|
|
bounds.predicates(astconv.tcx(), param_ty)
|
|
}
|
|
hir::GenericBound::LangItemTrait(lang_item, span, hir_id, args) => {
|
|
let mut bounds = Bounds::default();
|
|
astconv.instantiate_lang_item_trait_ref(
|
|
lang_item,
|
|
span,
|
|
hir_id,
|
|
args,
|
|
param_ty,
|
|
&mut bounds,
|
|
);
|
|
bounds.predicates(astconv.tcx(), param_ty)
|
|
}
|
|
hir::GenericBound::Outlives(ref lifetime) => {
|
|
let region = astconv.ast_region_to_region(lifetime, None);
|
|
let pred = ty::PredicateAtom::TypeOutlives(ty::OutlivesPredicate(param_ty, region))
|
|
.to_predicate(astconv.tcx());
|
|
vec![(pred, lifetime.span)]
|
|
}
|
|
}
|
|
}
|
|
|
|
fn compute_sig_of_foreign_fn_decl<'tcx>(
|
|
tcx: TyCtxt<'tcx>,
|
|
def_id: DefId,
|
|
decl: &'tcx hir::FnDecl<'tcx>,
|
|
abi: abi::Abi,
|
|
ident: Ident,
|
|
) -> ty::PolyFnSig<'tcx> {
|
|
let unsafety = if abi == abi::Abi::RustIntrinsic {
|
|
intrinsic_operation_unsafety(tcx.item_name(def_id))
|
|
} else {
|
|
hir::Unsafety::Unsafe
|
|
};
|
|
let fty = AstConv::ty_of_fn(
|
|
&ItemCtxt::new(tcx, def_id),
|
|
unsafety,
|
|
abi,
|
|
decl,
|
|
&hir::Generics::empty(),
|
|
Some(ident.span),
|
|
);
|
|
|
|
// Feature gate SIMD types in FFI, since I am not sure that the
|
|
// ABIs are handled at all correctly. -huonw
|
|
if abi != abi::Abi::RustIntrinsic
|
|
&& abi != abi::Abi::PlatformIntrinsic
|
|
&& !tcx.features().simd_ffi
|
|
{
|
|
let check = |ast_ty: &hir::Ty<'_>, ty: Ty<'_>| {
|
|
if ty.is_simd() {
|
|
let snip = tcx
|
|
.sess
|
|
.source_map()
|
|
.span_to_snippet(ast_ty.span)
|
|
.map_or(String::new(), |s| format!(" `{}`", s));
|
|
tcx.sess
|
|
.struct_span_err(
|
|
ast_ty.span,
|
|
&format!(
|
|
"use of SIMD type{} in FFI is highly experimental and \
|
|
may result in invalid code",
|
|
snip
|
|
),
|
|
)
|
|
.help("add `#![feature(simd_ffi)]` to the crate attributes to enable")
|
|
.emit();
|
|
}
|
|
};
|
|
for (input, ty) in decl.inputs.iter().zip(fty.inputs().skip_binder()) {
|
|
check(&input, ty)
|
|
}
|
|
if let hir::FnRetTy::Return(ref ty) = decl.output {
|
|
check(&ty, fty.output().skip_binder())
|
|
}
|
|
}
|
|
|
|
fty
|
|
}
|
|
|
|
fn is_foreign_item(tcx: TyCtxt<'_>, def_id: DefId) -> bool {
|
|
match tcx.hir().get_if_local(def_id) {
|
|
Some(Node::ForeignItem(..)) => true,
|
|
Some(_) => false,
|
|
_ => bug!("is_foreign_item applied to non-local def-id {:?}", def_id),
|
|
}
|
|
}
|
|
|
|
fn static_mutability(tcx: TyCtxt<'_>, def_id: DefId) -> Option<hir::Mutability> {
|
|
match tcx.hir().get_if_local(def_id) {
|
|
Some(
|
|
Node::Item(&hir::Item { kind: hir::ItemKind::Static(_, mutbl, _), .. })
|
|
| Node::ForeignItem(&hir::ForeignItem {
|
|
kind: hir::ForeignItemKind::Static(_, mutbl),
|
|
..
|
|
}),
|
|
) => Some(mutbl),
|
|
Some(_) => None,
|
|
_ => bug!("static_mutability applied to non-local def-id {:?}", def_id),
|
|
}
|
|
}
|
|
|
|
fn generator_kind(tcx: TyCtxt<'_>, def_id: DefId) -> Option<hir::GeneratorKind> {
|
|
match tcx.hir().get_if_local(def_id) {
|
|
Some(Node::Expr(&rustc_hir::Expr {
|
|
kind: rustc_hir::ExprKind::Closure(_, _, body_id, _, _),
|
|
..
|
|
})) => tcx.hir().body(body_id).generator_kind(),
|
|
Some(_) => None,
|
|
_ => bug!("generator_kind applied to non-local def-id {:?}", def_id),
|
|
}
|
|
}
|
|
|
|
fn from_target_feature(
|
|
tcx: TyCtxt<'_>,
|
|
id: DefId,
|
|
attr: &ast::Attribute,
|
|
supported_target_features: &FxHashMap<String, Option<Symbol>>,
|
|
target_features: &mut Vec<Symbol>,
|
|
) {
|
|
let list = match attr.meta_item_list() {
|
|
Some(list) => list,
|
|
None => return,
|
|
};
|
|
let bad_item = |span| {
|
|
let msg = "malformed `target_feature` attribute input";
|
|
let code = "enable = \"..\"".to_owned();
|
|
tcx.sess
|
|
.struct_span_err(span, &msg)
|
|
.span_suggestion(span, "must be of the form", code, Applicability::HasPlaceholders)
|
|
.emit();
|
|
};
|
|
let rust_features = tcx.features();
|
|
for item in list {
|
|
// Only `enable = ...` is accepted in the meta-item list.
|
|
if !item.has_name(sym::enable) {
|
|
bad_item(item.span());
|
|
continue;
|
|
}
|
|
|
|
// Must be of the form `enable = "..."` (a string).
|
|
let value = match item.value_str() {
|
|
Some(value) => value,
|
|
None => {
|
|
bad_item(item.span());
|
|
continue;
|
|
}
|
|
};
|
|
|
|
// We allow comma separation to enable multiple features.
|
|
target_features.extend(value.as_str().split(',').filter_map(|feature| {
|
|
let feature_gate = match supported_target_features.get(feature) {
|
|
Some(g) => g,
|
|
None => {
|
|
let msg =
|
|
format!("the feature named `{}` is not valid for this target", feature);
|
|
let mut err = tcx.sess.struct_span_err(item.span(), &msg);
|
|
err.span_label(
|
|
item.span(),
|
|
format!("`{}` is not valid for this target", feature),
|
|
);
|
|
if let Some(stripped) = feature.strip_prefix('+') {
|
|
let valid = supported_target_features.contains_key(stripped);
|
|
if valid {
|
|
err.help("consider removing the leading `+` in the feature name");
|
|
}
|
|
}
|
|
err.emit();
|
|
return None;
|
|
}
|
|
};
|
|
|
|
// Only allow features whose feature gates have been enabled.
|
|
let allowed = match feature_gate.as_ref().copied() {
|
|
Some(sym::arm_target_feature) => rust_features.arm_target_feature,
|
|
Some(sym::aarch64_target_feature) => rust_features.aarch64_target_feature,
|
|
Some(sym::hexagon_target_feature) => rust_features.hexagon_target_feature,
|
|
Some(sym::powerpc_target_feature) => rust_features.powerpc_target_feature,
|
|
Some(sym::mips_target_feature) => rust_features.mips_target_feature,
|
|
Some(sym::riscv_target_feature) => rust_features.riscv_target_feature,
|
|
Some(sym::avx512_target_feature) => rust_features.avx512_target_feature,
|
|
Some(sym::sse4a_target_feature) => rust_features.sse4a_target_feature,
|
|
Some(sym::tbm_target_feature) => rust_features.tbm_target_feature,
|
|
Some(sym::wasm_target_feature) => rust_features.wasm_target_feature,
|
|
Some(sym::cmpxchg16b_target_feature) => rust_features.cmpxchg16b_target_feature,
|
|
Some(sym::adx_target_feature) => rust_features.adx_target_feature,
|
|
Some(sym::movbe_target_feature) => rust_features.movbe_target_feature,
|
|
Some(sym::rtm_target_feature) => rust_features.rtm_target_feature,
|
|
Some(sym::f16c_target_feature) => rust_features.f16c_target_feature,
|
|
Some(sym::ermsb_target_feature) => rust_features.ermsb_target_feature,
|
|
Some(name) => bug!("unknown target feature gate {}", name),
|
|
None => true,
|
|
};
|
|
if !allowed && id.is_local() {
|
|
feature_err(
|
|
&tcx.sess.parse_sess,
|
|
feature_gate.unwrap(),
|
|
item.span(),
|
|
&format!("the target feature `{}` is currently unstable", feature),
|
|
)
|
|
.emit();
|
|
}
|
|
Some(Symbol::intern(feature))
|
|
}));
|
|
}
|
|
}
|
|
|
|
fn linkage_by_name(tcx: TyCtxt<'_>, def_id: DefId, name: &str) -> Linkage {
|
|
use rustc_middle::mir::mono::Linkage::*;
|
|
|
|
// Use the names from src/llvm/docs/LangRef.rst here. Most types are only
|
|
// applicable to variable declarations and may not really make sense for
|
|
// Rust code in the first place but allow them anyway and trust that the
|
|
// user knows what s/he's doing. Who knows, unanticipated use cases may pop
|
|
// up in the future.
|
|
//
|
|
// ghost, dllimport, dllexport and linkonce_odr_autohide are not supported
|
|
// and don't have to be, LLVM treats them as no-ops.
|
|
match name {
|
|
"appending" => Appending,
|
|
"available_externally" => AvailableExternally,
|
|
"common" => Common,
|
|
"extern_weak" => ExternalWeak,
|
|
"external" => External,
|
|
"internal" => Internal,
|
|
"linkonce" => LinkOnceAny,
|
|
"linkonce_odr" => LinkOnceODR,
|
|
"private" => Private,
|
|
"weak" => WeakAny,
|
|
"weak_odr" => WeakODR,
|
|
_ => {
|
|
let span = tcx.hir().span_if_local(def_id);
|
|
if let Some(span) = span {
|
|
tcx.sess.span_fatal(span, "invalid linkage specified")
|
|
} else {
|
|
tcx.sess.fatal(&format!("invalid linkage specified: {}", name))
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
fn codegen_fn_attrs(tcx: TyCtxt<'_>, id: DefId) -> CodegenFnAttrs {
|
|
let attrs = tcx.get_attrs(id);
|
|
|
|
let mut codegen_fn_attrs = CodegenFnAttrs::new();
|
|
if should_inherit_track_caller(tcx, id) {
|
|
codegen_fn_attrs.flags |= CodegenFnAttrFlags::TRACK_CALLER;
|
|
}
|
|
|
|
let supported_target_features = tcx.supported_target_features(LOCAL_CRATE);
|
|
|
|
let mut inline_span = None;
|
|
let mut link_ordinal_span = None;
|
|
let mut no_sanitize_span = None;
|
|
for attr in attrs.iter() {
|
|
if tcx.sess.check_name(attr, sym::cold) {
|
|
codegen_fn_attrs.flags |= CodegenFnAttrFlags::COLD;
|
|
} else if tcx.sess.check_name(attr, sym::rustc_allocator) {
|
|
codegen_fn_attrs.flags |= CodegenFnAttrFlags::ALLOCATOR;
|
|
} else if tcx.sess.check_name(attr, sym::unwind) {
|
|
codegen_fn_attrs.flags |= CodegenFnAttrFlags::UNWIND;
|
|
} else if tcx.sess.check_name(attr, sym::ffi_returns_twice) {
|
|
if tcx.is_foreign_item(id) {
|
|
codegen_fn_attrs.flags |= CodegenFnAttrFlags::FFI_RETURNS_TWICE;
|
|
} else {
|
|
// `#[ffi_returns_twice]` is only allowed `extern fn`s.
|
|
struct_span_err!(
|
|
tcx.sess,
|
|
attr.span,
|
|
E0724,
|
|
"`#[ffi_returns_twice]` may only be used on foreign functions"
|
|
)
|
|
.emit();
|
|
}
|
|
} else if tcx.sess.check_name(attr, sym::ffi_pure) {
|
|
if tcx.is_foreign_item(id) {
|
|
if attrs.iter().any(|a| tcx.sess.check_name(a, sym::ffi_const)) {
|
|
// `#[ffi_const]` functions cannot be `#[ffi_pure]`
|
|
struct_span_err!(
|
|
tcx.sess,
|
|
attr.span,
|
|
E0757,
|
|
"`#[ffi_const]` function cannot be `#[ffi_pure]`"
|
|
)
|
|
.emit();
|
|
} else {
|
|
codegen_fn_attrs.flags |= CodegenFnAttrFlags::FFI_PURE;
|
|
}
|
|
} else {
|
|
// `#[ffi_pure]` is only allowed on foreign functions
|
|
struct_span_err!(
|
|
tcx.sess,
|
|
attr.span,
|
|
E0755,
|
|
"`#[ffi_pure]` may only be used on foreign functions"
|
|
)
|
|
.emit();
|
|
}
|
|
} else if tcx.sess.check_name(attr, sym::ffi_const) {
|
|
if tcx.is_foreign_item(id) {
|
|
codegen_fn_attrs.flags |= CodegenFnAttrFlags::FFI_CONST;
|
|
} else {
|
|
// `#[ffi_const]` is only allowed on foreign functions
|
|
struct_span_err!(
|
|
tcx.sess,
|
|
attr.span,
|
|
E0756,
|
|
"`#[ffi_const]` may only be used on foreign functions"
|
|
)
|
|
.emit();
|
|
}
|
|
} else if tcx.sess.check_name(attr, sym::rustc_allocator_nounwind) {
|
|
codegen_fn_attrs.flags |= CodegenFnAttrFlags::RUSTC_ALLOCATOR_NOUNWIND;
|
|
} else if tcx.sess.check_name(attr, sym::naked) {
|
|
codegen_fn_attrs.flags |= CodegenFnAttrFlags::NAKED;
|
|
} else if tcx.sess.check_name(attr, sym::no_mangle) {
|
|
codegen_fn_attrs.flags |= CodegenFnAttrFlags::NO_MANGLE;
|
|
} else if tcx.sess.check_name(attr, sym::rustc_std_internal_symbol) {
|
|
codegen_fn_attrs.flags |= CodegenFnAttrFlags::RUSTC_STD_INTERNAL_SYMBOL;
|
|
} else if tcx.sess.check_name(attr, sym::used) {
|
|
codegen_fn_attrs.flags |= CodegenFnAttrFlags::USED;
|
|
} else if tcx.sess.check_name(attr, sym::cmse_nonsecure_entry) {
|
|
if tcx.fn_sig(id).abi() != abi::Abi::C {
|
|
struct_span_err!(
|
|
tcx.sess,
|
|
attr.span,
|
|
E0776,
|
|
"`#[cmse_nonsecure_entry]` requires C ABI"
|
|
)
|
|
.emit();
|
|
}
|
|
if !tcx.sess.target.llvm_target.contains("thumbv8m") {
|
|
struct_span_err!(tcx.sess, attr.span, E0775, "`#[cmse_nonsecure_entry]` is only valid for targets with the TrustZone-M extension")
|
|
.emit();
|
|
}
|
|
codegen_fn_attrs.flags |= CodegenFnAttrFlags::CMSE_NONSECURE_ENTRY;
|
|
} else if tcx.sess.check_name(attr, sym::thread_local) {
|
|
codegen_fn_attrs.flags |= CodegenFnAttrFlags::THREAD_LOCAL;
|
|
} else if tcx.sess.check_name(attr, sym::track_caller) {
|
|
if tcx.is_closure(id) || tcx.fn_sig(id).abi() != abi::Abi::Rust {
|
|
struct_span_err!(tcx.sess, attr.span, E0737, "`#[track_caller]` requires Rust ABI")
|
|
.emit();
|
|
}
|
|
codegen_fn_attrs.flags |= CodegenFnAttrFlags::TRACK_CALLER;
|
|
} else if tcx.sess.check_name(attr, sym::export_name) {
|
|
if let Some(s) = attr.value_str() {
|
|
if s.as_str().contains('\0') {
|
|
// `#[export_name = ...]` will be converted to a null-terminated string,
|
|
// so it may not contain any null characters.
|
|
struct_span_err!(
|
|
tcx.sess,
|
|
attr.span,
|
|
E0648,
|
|
"`export_name` may not contain null characters"
|
|
)
|
|
.emit();
|
|
}
|
|
codegen_fn_attrs.export_name = Some(s);
|
|
}
|
|
} else if tcx.sess.check_name(attr, sym::target_feature) {
|
|
if !tcx.is_closure(id) && tcx.fn_sig(id).unsafety() == hir::Unsafety::Normal {
|
|
if !tcx.features().target_feature_11 {
|
|
let mut err = feature_err(
|
|
&tcx.sess.parse_sess,
|
|
sym::target_feature_11,
|
|
attr.span,
|
|
"`#[target_feature(..)]` can only be applied to `unsafe` functions",
|
|
);
|
|
err.span_label(tcx.def_span(id), "not an `unsafe` function");
|
|
err.emit();
|
|
} else if let Some(local_id) = id.as_local() {
|
|
check_target_feature_trait_unsafe(tcx, local_id, attr.span);
|
|
}
|
|
}
|
|
from_target_feature(
|
|
tcx,
|
|
id,
|
|
attr,
|
|
&supported_target_features,
|
|
&mut codegen_fn_attrs.target_features,
|
|
);
|
|
} else if tcx.sess.check_name(attr, sym::linkage) {
|
|
if let Some(val) = attr.value_str() {
|
|
codegen_fn_attrs.linkage = Some(linkage_by_name(tcx, id, &val.as_str()));
|
|
}
|
|
} else if tcx.sess.check_name(attr, sym::link_section) {
|
|
if let Some(val) = attr.value_str() {
|
|
if val.as_str().bytes().any(|b| b == 0) {
|
|
let msg = format!(
|
|
"illegal null byte in link_section \
|
|
value: `{}`",
|
|
&val
|
|
);
|
|
tcx.sess.span_err(attr.span, &msg);
|
|
} else {
|
|
codegen_fn_attrs.link_section = Some(val);
|
|
}
|
|
}
|
|
} else if tcx.sess.check_name(attr, sym::link_name) {
|
|
codegen_fn_attrs.link_name = attr.value_str();
|
|
} else if tcx.sess.check_name(attr, sym::link_ordinal) {
|
|
link_ordinal_span = Some(attr.span);
|
|
if let ordinal @ Some(_) = check_link_ordinal(tcx, attr) {
|
|
codegen_fn_attrs.link_ordinal = ordinal;
|
|
}
|
|
} else if tcx.sess.check_name(attr, sym::no_sanitize) {
|
|
no_sanitize_span = Some(attr.span);
|
|
if let Some(list) = attr.meta_item_list() {
|
|
for item in list.iter() {
|
|
if item.has_name(sym::address) {
|
|
codegen_fn_attrs.no_sanitize |= SanitizerSet::ADDRESS;
|
|
} else if item.has_name(sym::memory) {
|
|
codegen_fn_attrs.no_sanitize |= SanitizerSet::MEMORY;
|
|
} else if item.has_name(sym::thread) {
|
|
codegen_fn_attrs.no_sanitize |= SanitizerSet::THREAD;
|
|
} else {
|
|
tcx.sess
|
|
.struct_span_err(item.span(), "invalid argument for `no_sanitize`")
|
|
.note("expected one of: `address`, `memory` or `thread`")
|
|
.emit();
|
|
}
|
|
}
|
|
}
|
|
} else if tcx.sess.check_name(attr, sym::instruction_set) {
|
|
codegen_fn_attrs.instruction_set = match attr.meta().map(|i| i.kind) {
|
|
Some(MetaItemKind::List(ref items)) => match items.as_slice() {
|
|
[NestedMetaItem::MetaItem(set)] => {
|
|
let segments =
|
|
set.path.segments.iter().map(|x| x.ident.name).collect::<Vec<_>>();
|
|
match segments.as_slice() {
|
|
[sym::arm, sym::a32] | [sym::arm, sym::t32] => {
|
|
if !tcx.sess.target.has_thumb_interworking {
|
|
struct_span_err!(
|
|
tcx.sess.diagnostic(),
|
|
attr.span,
|
|
E0779,
|
|
"target does not support `#[instruction_set]`"
|
|
)
|
|
.emit();
|
|
None
|
|
} else if segments[1] == sym::a32 {
|
|
Some(InstructionSetAttr::ArmA32)
|
|
} else if segments[1] == sym::t32 {
|
|
Some(InstructionSetAttr::ArmT32)
|
|
} else {
|
|
unreachable!()
|
|
}
|
|
}
|
|
_ => {
|
|
struct_span_err!(
|
|
tcx.sess.diagnostic(),
|
|
attr.span,
|
|
E0779,
|
|
"invalid instruction set specified",
|
|
)
|
|
.emit();
|
|
None
|
|
}
|
|
}
|
|
}
|
|
[] => {
|
|
struct_span_err!(
|
|
tcx.sess.diagnostic(),
|
|
attr.span,
|
|
E0778,
|
|
"`#[instruction_set]` requires an argument"
|
|
)
|
|
.emit();
|
|
None
|
|
}
|
|
_ => {
|
|
struct_span_err!(
|
|
tcx.sess.diagnostic(),
|
|
attr.span,
|
|
E0779,
|
|
"cannot specify more than one instruction set"
|
|
)
|
|
.emit();
|
|
None
|
|
}
|
|
},
|
|
_ => {
|
|
struct_span_err!(
|
|
tcx.sess.diagnostic(),
|
|
attr.span,
|
|
E0778,
|
|
"must specify an instruction set"
|
|
)
|
|
.emit();
|
|
None
|
|
}
|
|
};
|
|
}
|
|
}
|
|
|
|
codegen_fn_attrs.inline = attrs.iter().fold(InlineAttr::None, |ia, attr| {
|
|
if !attr.has_name(sym::inline) {
|
|
return ia;
|
|
}
|
|
match attr.meta().map(|i| i.kind) {
|
|
Some(MetaItemKind::Word) => {
|
|
tcx.sess.mark_attr_used(attr);
|
|
InlineAttr::Hint
|
|
}
|
|
Some(MetaItemKind::List(ref items)) => {
|
|
tcx.sess.mark_attr_used(attr);
|
|
inline_span = Some(attr.span);
|
|
if items.len() != 1 {
|
|
struct_span_err!(
|
|
tcx.sess.diagnostic(),
|
|
attr.span,
|
|
E0534,
|
|
"expected one argument"
|
|
)
|
|
.emit();
|
|
InlineAttr::None
|
|
} else if list_contains_name(&items[..], sym::always) {
|
|
InlineAttr::Always
|
|
} else if list_contains_name(&items[..], sym::never) {
|
|
InlineAttr::Never
|
|
} else {
|
|
struct_span_err!(
|
|
tcx.sess.diagnostic(),
|
|
items[0].span(),
|
|
E0535,
|
|
"invalid argument"
|
|
)
|
|
.emit();
|
|
|
|
InlineAttr::None
|
|
}
|
|
}
|
|
Some(MetaItemKind::NameValue(_)) => ia,
|
|
None => ia,
|
|
}
|
|
});
|
|
|
|
codegen_fn_attrs.optimize = attrs.iter().fold(OptimizeAttr::None, |ia, attr| {
|
|
if !attr.has_name(sym::optimize) {
|
|
return ia;
|
|
}
|
|
let err = |sp, s| struct_span_err!(tcx.sess.diagnostic(), sp, E0722, "{}", s).emit();
|
|
match attr.meta().map(|i| i.kind) {
|
|
Some(MetaItemKind::Word) => {
|
|
err(attr.span, "expected one argument");
|
|
ia
|
|
}
|
|
Some(MetaItemKind::List(ref items)) => {
|
|
tcx.sess.mark_attr_used(attr);
|
|
inline_span = Some(attr.span);
|
|
if items.len() != 1 {
|
|
err(attr.span, "expected one argument");
|
|
OptimizeAttr::None
|
|
} else if list_contains_name(&items[..], sym::size) {
|
|
OptimizeAttr::Size
|
|
} else if list_contains_name(&items[..], sym::speed) {
|
|
OptimizeAttr::Speed
|
|
} else {
|
|
err(items[0].span(), "invalid argument");
|
|
OptimizeAttr::None
|
|
}
|
|
}
|
|
Some(MetaItemKind::NameValue(_)) => ia,
|
|
None => ia,
|
|
}
|
|
});
|
|
|
|
// #73631: closures inherit `#[target_feature]` annotations
|
|
if tcx.features().target_feature_11 && tcx.is_closure(id) {
|
|
let owner_id = tcx.parent(id).expect("closure should have a parent");
|
|
codegen_fn_attrs
|
|
.target_features
|
|
.extend(tcx.codegen_fn_attrs(owner_id).target_features.iter().copied())
|
|
}
|
|
|
|
// If a function uses #[target_feature] it can't be inlined into general
|
|
// purpose functions as they wouldn't have the right target features
|
|
// enabled. For that reason we also forbid #[inline(always)] as it can't be
|
|
// respected.
|
|
if !codegen_fn_attrs.target_features.is_empty() {
|
|
if codegen_fn_attrs.inline == InlineAttr::Always {
|
|
if let Some(span) = inline_span {
|
|
tcx.sess.span_err(
|
|
span,
|
|
"cannot use `#[inline(always)]` with \
|
|
`#[target_feature]`",
|
|
);
|
|
}
|
|
}
|
|
}
|
|
|
|
if !codegen_fn_attrs.no_sanitize.is_empty() {
|
|
if codegen_fn_attrs.inline == InlineAttr::Always {
|
|
if let (Some(no_sanitize_span), Some(inline_span)) = (no_sanitize_span, inline_span) {
|
|
let hir_id = tcx.hir().local_def_id_to_hir_id(id.expect_local());
|
|
tcx.struct_span_lint_hir(
|
|
lint::builtin::INLINE_NO_SANITIZE,
|
|
hir_id,
|
|
no_sanitize_span,
|
|
|lint| {
|
|
lint.build("`no_sanitize` will have no effect after inlining")
|
|
.span_note(inline_span, "inlining requested here")
|
|
.emit();
|
|
},
|
|
)
|
|
}
|
|
}
|
|
}
|
|
|
|
// Weak lang items have the same semantics as "std internal" symbols in the
|
|
// sense that they're preserved through all our LTO passes and only
|
|
// strippable by the linker.
|
|
//
|
|
// Additionally weak lang items have predetermined symbol names.
|
|
if tcx.is_weak_lang_item(id) {
|
|
codegen_fn_attrs.flags |= CodegenFnAttrFlags::RUSTC_STD_INTERNAL_SYMBOL;
|
|
}
|
|
let check_name = |attr, sym| tcx.sess.check_name(attr, sym);
|
|
if let Some(name) = weak_lang_items::link_name(check_name, &attrs) {
|
|
codegen_fn_attrs.export_name = Some(name);
|
|
codegen_fn_attrs.link_name = Some(name);
|
|
}
|
|
check_link_name_xor_ordinal(tcx, &codegen_fn_attrs, link_ordinal_span);
|
|
|
|
// Internal symbols to the standard library all have no_mangle semantics in
|
|
// that they have defined symbol names present in the function name. This
|
|
// also applies to weak symbols where they all have known symbol names.
|
|
if codegen_fn_attrs.flags.contains(CodegenFnAttrFlags::RUSTC_STD_INTERNAL_SYMBOL) {
|
|
codegen_fn_attrs.flags |= CodegenFnAttrFlags::NO_MANGLE;
|
|
}
|
|
|
|
codegen_fn_attrs
|
|
}
|
|
|
|
/// Checks if the provided DefId is a method in a trait impl for a trait which has track_caller
|
|
/// applied to the method prototype.
|
|
fn should_inherit_track_caller(tcx: TyCtxt<'_>, def_id: DefId) -> bool {
|
|
if let Some(impl_item) = tcx.opt_associated_item(def_id) {
|
|
if let ty::AssocItemContainer::ImplContainer(impl_def_id) = impl_item.container {
|
|
if let Some(trait_def_id) = tcx.trait_id_of_impl(impl_def_id) {
|
|
if let Some(trait_item) = tcx
|
|
.associated_items(trait_def_id)
|
|
.filter_by_name_unhygienic(impl_item.ident.name)
|
|
.find(move |trait_item| {
|
|
trait_item.kind == ty::AssocKind::Fn
|
|
&& tcx.hygienic_eq(impl_item.ident, trait_item.ident, trait_def_id)
|
|
})
|
|
{
|
|
return tcx
|
|
.codegen_fn_attrs(trait_item.def_id)
|
|
.flags
|
|
.intersects(CodegenFnAttrFlags::TRACK_CALLER);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
false
|
|
}
|
|
|
|
fn check_link_ordinal(tcx: TyCtxt<'_>, attr: &ast::Attribute) -> Option<usize> {
|
|
use rustc_ast::{Lit, LitIntType, LitKind};
|
|
let meta_item_list = attr.meta_item_list();
|
|
let meta_item_list: Option<&[ast::NestedMetaItem]> = meta_item_list.as_ref().map(Vec::as_ref);
|
|
let sole_meta_list = match meta_item_list {
|
|
Some([item]) => item.literal(),
|
|
_ => None,
|
|
};
|
|
if let Some(Lit { kind: LitKind::Int(ordinal, LitIntType::Unsuffixed), .. }) = sole_meta_list {
|
|
if *ordinal <= usize::MAX as u128 {
|
|
Some(*ordinal as usize)
|
|
} else {
|
|
let msg = format!("ordinal value in `link_ordinal` is too large: `{}`", &ordinal);
|
|
tcx.sess
|
|
.struct_span_err(attr.span, &msg)
|
|
.note("the value may not exceed `usize::MAX`")
|
|
.emit();
|
|
None
|
|
}
|
|
} else {
|
|
tcx.sess
|
|
.struct_span_err(attr.span, "illegal ordinal format in `link_ordinal`")
|
|
.note("an unsuffixed integer value, e.g., `1`, is expected")
|
|
.emit();
|
|
None
|
|
}
|
|
}
|
|
|
|
fn check_link_name_xor_ordinal(
|
|
tcx: TyCtxt<'_>,
|
|
codegen_fn_attrs: &CodegenFnAttrs,
|
|
inline_span: Option<Span>,
|
|
) {
|
|
if codegen_fn_attrs.link_name.is_none() || codegen_fn_attrs.link_ordinal.is_none() {
|
|
return;
|
|
}
|
|
let msg = "cannot use `#[link_name]` with `#[link_ordinal]`";
|
|
if let Some(span) = inline_span {
|
|
tcx.sess.span_err(span, msg);
|
|
} else {
|
|
tcx.sess.err(msg);
|
|
}
|
|
}
|
|
|
|
/// Checks the function annotated with `#[target_feature]` is not a safe
|
|
/// trait method implementation, reporting an error if it is.
|
|
fn check_target_feature_trait_unsafe(tcx: TyCtxt<'_>, id: LocalDefId, attr_span: Span) {
|
|
let hir_id = tcx.hir().local_def_id_to_hir_id(id);
|
|
let node = tcx.hir().get(hir_id);
|
|
if let Node::ImplItem(hir::ImplItem { kind: hir::ImplItemKind::Fn(..), .. }) = node {
|
|
let parent_id = tcx.hir().get_parent_item(hir_id);
|
|
let parent_item = tcx.hir().expect_item(parent_id);
|
|
if let hir::ItemKind::Impl { of_trait: Some(_), .. } = parent_item.kind {
|
|
tcx.sess
|
|
.struct_span_err(
|
|
attr_span,
|
|
"`#[target_feature(..)]` cannot be applied to safe trait method",
|
|
)
|
|
.span_label(attr_span, "cannot be applied to safe trait method")
|
|
.span_label(tcx.def_span(id), "not an `unsafe` function")
|
|
.emit();
|
|
}
|
|
}
|
|
}
|