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2d28b6384e
Unsafe extern blocks This implements RFC 3484. Tracking issue #123743 and RFC https://github.com/rust-lang/rfcs/pull/3484 This is better reviewed commit by commit.
1865 lines
70 KiB
Rust
1865 lines
70 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 rustc_ast::Recovered;
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use rustc_data_structures::captures::Captures;
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use rustc_data_structures::fx::{FxHashSet, FxIndexMap};
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use rustc_data_structures::unord::UnordMap;
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use rustc_errors::{struct_span_code_err, Applicability, Diag, ErrorGuaranteed, StashKey, E0228};
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use rustc_hir::def::DefKind;
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use rustc_hir::def_id::{DefId, LocalDefId};
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use rustc_hir::intravisit::{self, walk_generics, Visitor};
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use rustc_hir::{self as hir};
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use rustc_hir::{GenericParamKind, Node};
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use rustc_infer::infer::{InferCtxt, TyCtxtInferExt};
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use rustc_infer::traits::ObligationCause;
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use rustc_middle::hir::nested_filter;
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use rustc_middle::query::Providers;
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use rustc_middle::ty::util::{Discr, IntTypeExt};
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use rustc_middle::ty::{self, AdtKind, Const, IsSuggestable, Ty, TyCtxt, Upcast};
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use rustc_middle::{bug, span_bug};
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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::abi::FieldIdx;
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use rustc_target::spec::abi;
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use rustc_trait_selection::infer::InferCtxtExt;
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use rustc_trait_selection::traits::error_reporting::suggestions::NextTypeParamName;
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use rustc_trait_selection::traits::ObligationCtxt;
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use std::cell::Cell;
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use std::iter;
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use std::ops::Bound;
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use crate::check::intrinsic::intrinsic_operation_unsafety;
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use crate::errors;
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use crate::hir_ty_lowering::{HirTyLowerer, RegionInferReason};
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pub use type_of::test_opaque_hidden_types;
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mod generics_of;
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mod item_bounds;
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mod predicates_of;
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mod resolve_bound_vars;
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mod type_of;
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///////////////////////////////////////////////////////////////////////////
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pub fn provide(providers: &mut Providers) {
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resolve_bound_vars::provide(providers);
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*providers = Providers {
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type_of: type_of::type_of,
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type_of_opaque: type_of::type_of_opaque,
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type_alias_is_lazy: type_of::type_alias_is_lazy,
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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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item_super_predicates: item_bounds::item_super_predicates,
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explicit_item_super_predicates: item_bounds::explicit_item_super_predicates,
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item_non_self_assumptions: item_bounds::item_non_self_assumptions,
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generics_of: generics_of::generics_of,
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predicates_of: predicates_of::predicates_of,
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predicates_defined_on,
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explicit_predicates_of: predicates_of::explicit_predicates_of,
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super_predicates_of: predicates_of::super_predicates_of,
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implied_predicates_of: predicates_of::implied_predicates_of,
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super_predicates_that_define_assoc_item:
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predicates_of::super_predicates_that_define_assoc_item,
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trait_explicit_predicates_and_bounds: predicates_of::trait_explicit_predicates_and_bounds,
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type_param_predicates: predicates_of::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_header,
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coroutine_kind,
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coroutine_for_closure,
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is_type_alias_impl_trait,
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find_field,
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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 [`HirTyLowerer`].
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///
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/// # `ItemCtxt` vs `FnCtxt`
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///
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/// `ItemCtxt` is primarily used to type-check item signatures and lower them
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/// from HIR to their [`ty::Ty`] representation, which is exposed using [`HirTyLowerer`].
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/// It's also used for the bodies of items like structs where the body (the fields)
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/// are just signatures.
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///
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/// This is in contrast to `FnCtxt`, which is used to type-check bodies of
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/// functions, closures, and `const`s -- anywhere that expressions and statements show up.
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///
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/// An important thing to note is that `ItemCtxt` does no inference -- it has no [`InferCtxt`] --
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/// while `FnCtxt` does do inference.
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///
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/// [`InferCtxt`]: rustc_infer::infer::InferCtxt
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///
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/// # Trait predicates
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///
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/// `ItemCtxt` 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 HIR 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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/// `probe_ty_param_bounds` requests, drawing the information from
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/// the HIR (`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: LocalDefId,
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tainted_by_errors: Cell<Option<ErrorGuaranteed>>,
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}
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///////////////////////////////////////////////////////////////////////////
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#[derive(Default)]
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pub(crate) struct HirPlaceholderCollector(pub(crate) Vec<Span>);
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impl<'v> Visitor<'v> for HirPlaceholderCollector {
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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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fn visit_generic_arg(&mut self, generic_arg: &'v hir::GenericArg<'v>) {
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match generic_arg {
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hir::GenericArg::Infer(inf) => {
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self.0.push(inf.span);
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intravisit::walk_inf(self, inf);
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}
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hir::GenericArg::Type(t) => self.visit_ty(t),
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_ => {}
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}
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}
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fn visit_array_length(&mut self, length: &'v hir::ArrayLen<'v>) {
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if let hir::ArrayLen::Infer(inf) = length {
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self.0.push(inf.span);
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}
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intravisit::walk_array_len(self, length)
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}
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}
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pub struct CollectItemTypesVisitor<'tcx> {
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pub 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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pub(crate) fn placeholder_type_error<'tcx>(
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tcx: TyCtxt<'tcx>,
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generics: Option<&hir::Generics<'_>>,
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placeholder_types: Vec<Span>,
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suggest: bool,
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hir_ty: Option<&hir::Ty<'_>>,
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kind: &'static str,
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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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placeholder_type_error_diag(tcx, generics, placeholder_types, vec![], suggest, hir_ty, kind)
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.emit();
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}
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pub(crate) fn placeholder_type_error_diag<'tcx>(
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tcx: TyCtxt<'tcx>,
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generics: Option<&hir::Generics<'_>>,
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placeholder_types: Vec<Span>,
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additional_spans: Vec<Span>,
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suggest: bool,
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hir_ty: Option<&hir::Ty<'_>>,
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kind: &'static str,
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) -> Diag<'tcx> {
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if placeholder_types.is_empty() {
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return bad_placeholder(tcx, additional_spans, kind);
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}
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let params = generics.map(|g| g.params).unwrap_or_default();
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let type_name = params.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 let Some(generics) = generics {
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if let Some(arg) = params.iter().find(|arg| {
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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 if let Some(span) = generics.span_for_param_suggestion() {
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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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sugg.push((span, format!(", {type_name}")));
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} else {
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sugg.push((generics.span, format!("<{type_name}>")));
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}
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}
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let mut err =
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bad_placeholder(tcx, placeholder_types.into_iter().chain(additional_spans).collect(), kind);
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// Suggest, but only if it is not a function in const or static
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if suggest {
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let mut is_fn = false;
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let mut is_const_or_static = false;
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if let Some(hir_ty) = hir_ty
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&& let hir::TyKind::BareFn(_) = hir_ty.kind
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{
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is_fn = true;
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// Check if parent is const or static
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is_const_or_static = matches!(
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tcx.parent_hir_node(hir_ty.hir_id),
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Node::Item(&hir::Item {
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kind: hir::ItemKind::Const(..) | hir::ItemKind::Static(..),
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..
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}) | Node::TraitItem(&hir::TraitItem { kind: hir::TraitItemKind::Const(..), .. })
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| Node::ImplItem(&hir::ImplItem { kind: hir::ImplItemKind::Const(..), .. })
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);
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}
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// if function is wrapped around a const or static,
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// then don't show the suggestion
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if !(is_fn && is_const_or_static) {
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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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}
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err
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}
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fn reject_placeholder_type_signatures_in_item<'tcx>(
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tcx: TyCtxt<'tcx>,
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item: &'tcx hir::Item<'tcx>,
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) {
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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(hir::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 = HirPlaceholderCollector::default();
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visitor.visit_item(item);
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placeholder_type_error(tcx, Some(generics), visitor.0, suggest, None, item.kind.descr());
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}
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impl<'tcx> Visitor<'tcx> for CollectItemTypesVisitor<'tcx> {
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type NestedFilter = nested_filter::OnlyBodies;
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fn nested_visit_map(&mut self) -> Self::Map {
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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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lower_item(self.tcx, item.item_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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self.tcx.ensure().type_of(param.def_id);
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}
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hir::GenericParamKind::Type { .. } => {}
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hir::GenericParamKind::Const { default, .. } => {
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self.tcx.ensure().type_of(param.def_id);
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if let Some(default) = default {
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// need to store default and type of default
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self.tcx.ensure().type_of(default.def_id);
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self.tcx.ensure().const_param_default(param.def_id);
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}
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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(closure) = expr.kind {
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self.tcx.ensure().generics_of(closure.def_id);
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self.tcx.ensure().codegen_fn_attrs(closure.def_id);
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// We do not call `type_of` for closures here as that
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// depends on typecheck and would therefore hide
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// any further errors in case one typeck fails.
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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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lower_trait_item(self.tcx, trait_item.trait_item_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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lower_impl_item(self.tcx, impl_item.impl_item_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<'tcx>(
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tcx: TyCtxt<'tcx>,
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mut spans: Vec<Span>,
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kind: &'static str,
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) -> Diag<'tcx> {
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let kind = if kind.ends_with('s') { format!("{kind}es") } else { format!("{kind}s") };
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spans.sort();
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tcx.dcx().create_err(errors::PlaceholderNotAllowedItemSignatures { spans, kind })
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}
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impl<'tcx> ItemCtxt<'tcx> {
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pub fn new(tcx: TyCtxt<'tcx>, item_def_id: LocalDefId) -> ItemCtxt<'tcx> {
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ItemCtxt { tcx, item_def_id, tainted_by_errors: Cell::new(None) }
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}
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pub fn lower_ty(&self, hir_ty: &hir::Ty<'tcx>) -> Ty<'tcx> {
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self.lowerer().lower_ty(hir_ty)
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}
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pub fn hir_id(&self) -> hir::HirId {
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self.tcx.local_def_id_to_hir_id(self.item_def_id)
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}
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pub fn node(&self) -> hir::Node<'tcx> {
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self.tcx.hir_node(self.hir_id())
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}
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fn check_tainted_by_errors(&self) -> Result<(), ErrorGuaranteed> {
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match self.tainted_by_errors.get() {
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Some(err) => Err(err),
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None => Ok(()),
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}
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}
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}
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impl<'tcx> HirTyLowerer<'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) -> LocalDefId {
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self.item_def_id
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}
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fn re_infer(&self, span: Span, reason: RegionInferReason<'_>) -> ty::Region<'tcx> {
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if let RegionInferReason::BorrowedObjectLifetimeDefault = reason {
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let e = struct_span_code_err!(
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self.tcx().dcx(),
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span,
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E0228,
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"the lifetime bound for this object type cannot be deduced \
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from context; please supply an explicit bound"
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)
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.emit();
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self.set_tainted_by_errors(e);
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ty::Region::new_error(self.tcx(), e)
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} else {
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// This indicates an illegal lifetime in a non-assoc-trait position
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ty::Region::new_error_with_message(self.tcx(), span, "unelided lifetime in signature")
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}
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}
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fn ty_infer(&self, _: Option<&ty::GenericParamDef>, span: Span) -> Ty<'tcx> {
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Ty::new_error_with_message(self.tcx(), span, "bad placeholder type")
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}
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fn ct_infer(&self, _: Option<&ty::GenericParamDef>, span: Span) -> Const<'tcx> {
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ty::Const::new_error_with_message(self.tcx(), span, "bad placeholder constant")
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}
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|
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|
fn probe_ty_param_bounds(
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&self,
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span: Span,
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def_id: LocalDefId,
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|
assoc_name: Ident,
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) -> ty::GenericPredicates<'tcx> {
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self.tcx.at(span).type_param_predicates((self.item_def_id, def_id, assoc_name))
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}
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|
|
fn lower_assoc_ty(
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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<'tcx>,
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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_args = self.lowerer().lower_generic_args_of_assoc_item(
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span,
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item_def_id,
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item_segment,
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trait_ref.args,
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);
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Ty::new_projection(self.tcx(), item_def_id, item_args)
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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 mpart_sugg, mut inferred_sugg) = (None, None);
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let mut bound = String::new();
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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 = self
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|
.tcx
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|
.hir()
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|
.expect_item(self.tcx.hir().get_parent_item(self.hir_id()).def_id);
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|
match &item.kind {
|
|
hir::ItemKind::Enum(_, generics)
|
|
| hir::ItemKind::Struct(_, generics)
|
|
| hir::ItemKind::Union(_, generics) => {
|
|
let lt_name = get_new_lifetime_name(self.tcx, poly_trait_ref, generics);
|
|
let (lt_sp, sugg) = match generics.params {
|
|
[] => (generics.span, format!("<{lt_name}>")),
|
|
[bound, ..] => (bound.span.shrink_to_lo(), format!("{lt_name}, ")),
|
|
};
|
|
mpart_sugg = Some(errors::AssociatedTypeTraitUninferredGenericParamsMultipartSuggestion {
|
|
fspan: lt_sp,
|
|
first: sugg,
|
|
sspan: span.with_hi(item_segment.ident.span.lo()),
|
|
second: format!(
|
|
"{}::",
|
|
// Replace the existing lifetimes with a new named lifetime.
|
|
self.tcx.instantiate_bound_regions_uncached(
|
|
poly_trait_ref,
|
|
|_| {
|
|
ty::Region::new_early_param(self.tcx, ty::EarlyParamRegion {
|
|
index: 0,
|
|
name: Symbol::intern(<_name),
|
|
})
|
|
}
|
|
),
|
|
),
|
|
});
|
|
}
|
|
_ => {}
|
|
}
|
|
}
|
|
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(_) => {
|
|
inferred_sugg = Some(span.with_hi(item_segment.ident.span.lo()));
|
|
bound = format!(
|
|
"{}::",
|
|
// Erase named lt, we want `<A as B<'_>::C`, not `<A as B<'a>::C`.
|
|
self.tcx.anonymize_bound_vars(poly_trait_ref).skip_binder(),
|
|
);
|
|
}
|
|
_ => {}
|
|
}
|
|
Ty::new_error(
|
|
self.tcx(),
|
|
self.tcx().dcx().emit_err(errors::AssociatedTypeTraitUninferredGenericParams {
|
|
span,
|
|
inferred_sugg,
|
|
bound,
|
|
mpart_sugg,
|
|
}),
|
|
)
|
|
}
|
|
}
|
|
|
|
fn probe_adt(&self, _span: Span, ty: Ty<'tcx>) -> Option<ty::AdtDef<'tcx>> {
|
|
// FIXME(#103640): Should we handle the case where `ty` is a projection?
|
|
ty.ty_adt_def()
|
|
}
|
|
|
|
fn record_ty(&self, _hir_id: hir::HirId, _ty: Ty<'tcx>, _span: Span) {
|
|
// There's no place to record types from signatures?
|
|
}
|
|
|
|
fn infcx(&self) -> Option<&InferCtxt<'tcx>> {
|
|
None
|
|
}
|
|
|
|
fn set_tainted_by_errors(&self, err: ErrorGuaranteed) {
|
|
self.tainted_by_errors.set(Some(err));
|
|
}
|
|
|
|
fn lower_fn_sig(
|
|
&self,
|
|
decl: &hir::FnDecl<'tcx>,
|
|
generics: Option<&hir::Generics<'_>>,
|
|
hir_id: rustc_hir::HirId,
|
|
hir_ty: Option<&hir::Ty<'_>>,
|
|
) -> (Vec<Ty<'tcx>>, Ty<'tcx>) {
|
|
let tcx = self.tcx();
|
|
// We proactively collect all the inferred type params to emit a single error per fn def.
|
|
let mut visitor = HirPlaceholderCollector::default();
|
|
let mut infer_replacements = vec![];
|
|
|
|
if let Some(generics) = generics {
|
|
walk_generics(&mut visitor, generics);
|
|
}
|
|
|
|
let input_tys = decl
|
|
.inputs
|
|
.iter()
|
|
.enumerate()
|
|
.map(|(i, a)| {
|
|
if let hir::TyKind::Infer = a.kind {
|
|
if let Some(suggested_ty) =
|
|
self.lowerer().suggest_trait_fn_ty_for_impl_fn_infer(hir_id, Some(i))
|
|
{
|
|
infer_replacements.push((a.span, suggested_ty.to_string()));
|
|
return Ty::new_error_with_message(tcx, a.span, suggested_ty.to_string());
|
|
}
|
|
}
|
|
|
|
// Only visit the type looking for `_` if we didn't fix the type above
|
|
visitor.visit_ty(a);
|
|
self.lowerer().lower_arg_ty(a, None)
|
|
})
|
|
.collect();
|
|
|
|
let output_ty = match decl.output {
|
|
hir::FnRetTy::Return(output) => {
|
|
if let hir::TyKind::Infer = output.kind
|
|
&& let Some(suggested_ty) =
|
|
self.lowerer().suggest_trait_fn_ty_for_impl_fn_infer(hir_id, None)
|
|
{
|
|
infer_replacements.push((output.span, suggested_ty.to_string()));
|
|
Ty::new_error_with_message(tcx, output.span, suggested_ty.to_string())
|
|
} else {
|
|
visitor.visit_ty(output);
|
|
self.lower_ty(output)
|
|
}
|
|
}
|
|
hir::FnRetTy::DefaultReturn(..) => tcx.types.unit,
|
|
};
|
|
|
|
if !(visitor.0.is_empty() && infer_replacements.is_empty()) {
|
|
// We check for the presence of
|
|
// `ident_span` to not emit an error twice when we have `fn foo(_: fn() -> _)`.
|
|
|
|
let mut diag = crate::collect::placeholder_type_error_diag(
|
|
tcx,
|
|
generics,
|
|
visitor.0,
|
|
infer_replacements.iter().map(|(s, _)| *s).collect(),
|
|
true,
|
|
hir_ty,
|
|
"function",
|
|
);
|
|
|
|
if !infer_replacements.is_empty() {
|
|
diag.multipart_suggestion(
|
|
format!(
|
|
"try replacing `_` with the type{} in the corresponding trait method signature",
|
|
rustc_errors::pluralize!(infer_replacements.len()),
|
|
),
|
|
infer_replacements,
|
|
Applicability::MachineApplicable,
|
|
);
|
|
}
|
|
|
|
self.set_tainted_by_errors(diag.emit());
|
|
}
|
|
|
|
(input_tys, output_ty)
|
|
}
|
|
}
|
|
|
|
/// 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()
|
|
}
|
|
|
|
#[instrument(level = "debug", skip_all)]
|
|
fn lower_item(tcx: TyCtxt<'_>, item_id: hir::ItemId) {
|
|
let it = tcx.hir().item(item_id);
|
|
debug!(item = %it.ident, id = %it.hir_id());
|
|
let def_id = item_id.owner_id.def_id;
|
|
|
|
match &it.kind {
|
|
// These don't define types.
|
|
hir::ItemKind::ExternCrate(_)
|
|
| hir::ItemKind::Use(..)
|
|
| hir::ItemKind::Macro(..)
|
|
| hir::ItemKind::Mod(_)
|
|
| hir::ItemKind::GlobalAsm(_) => {}
|
|
hir::ItemKind::ForeignMod { items, .. } => {
|
|
for item in *items {
|
|
let item = tcx.hir().foreign_item(item.id);
|
|
tcx.ensure().generics_of(item.owner_id);
|
|
tcx.ensure().type_of(item.owner_id);
|
|
tcx.ensure().predicates_of(item.owner_id);
|
|
match item.kind {
|
|
hir::ForeignItemKind::Fn(..) => {
|
|
tcx.ensure().codegen_fn_attrs(item.owner_id);
|
|
tcx.ensure().fn_sig(item.owner_id)
|
|
}
|
|
hir::ForeignItemKind::Static(..) => {
|
|
tcx.ensure().codegen_fn_attrs(item.owner_id);
|
|
let mut visitor = HirPlaceholderCollector::default();
|
|
visitor.visit_foreign_item(item);
|
|
placeholder_type_error(
|
|
tcx,
|
|
None,
|
|
visitor.0,
|
|
false,
|
|
None,
|
|
"static variable",
|
|
);
|
|
}
|
|
_ => (),
|
|
}
|
|
}
|
|
}
|
|
hir::ItemKind::Enum(..) => {
|
|
tcx.ensure().generics_of(def_id);
|
|
tcx.ensure().type_of(def_id);
|
|
tcx.ensure().predicates_of(def_id);
|
|
lower_enum_variant_types(tcx, def_id.to_def_id());
|
|
}
|
|
hir::ItemKind::Impl { .. } => {
|
|
tcx.ensure().generics_of(def_id);
|
|
tcx.ensure().type_of(def_id);
|
|
tcx.ensure().impl_trait_header(def_id);
|
|
tcx.ensure().predicates_of(def_id);
|
|
tcx.ensure().associated_items(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);
|
|
tcx.ensure().associated_items(def_id);
|
|
}
|
|
hir::ItemKind::TraitAlias(..) => {
|
|
tcx.ensure().generics_of(def_id);
|
|
tcx.at(it.span).implied_predicates_of(def_id);
|
|
tcx.at(it.span).super_predicates_of(def_id);
|
|
tcx.ensure().predicates_of(def_id);
|
|
}
|
|
hir::ItemKind::Struct(struct_def, _) | hir::ItemKind::Union(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() {
|
|
tcx.ensure().generics_of(f.def_id);
|
|
tcx.ensure().type_of(f.def_id);
|
|
tcx.ensure().predicates_of(f.def_id);
|
|
}
|
|
|
|
if let Some(ctor_def_id) = struct_def.ctor_def_id() {
|
|
lower_variant_ctor(tcx, ctor_def_id);
|
|
}
|
|
}
|
|
|
|
// 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);
|
|
tcx.ensure().explicit_item_super_predicates(def_id);
|
|
tcx.ensure().item_bounds(def_id);
|
|
tcx.ensure().item_super_predicates(def_id);
|
|
}
|
|
|
|
hir::ItemKind::TyAlias(..) => {
|
|
tcx.ensure().generics_of(def_id);
|
|
tcx.ensure().type_of(def_id);
|
|
tcx.ensure().predicates_of(def_id);
|
|
}
|
|
|
|
hir::ItemKind::Static(ty, ..) | hir::ItemKind::Const(ty, ..) => {
|
|
tcx.ensure().generics_of(def_id);
|
|
tcx.ensure().type_of(def_id);
|
|
tcx.ensure().predicates_of(def_id);
|
|
if !ty.is_suggestable_infer_ty() {
|
|
let mut visitor = HirPlaceholderCollector::default();
|
|
visitor.visit_item(it);
|
|
placeholder_type_error(tcx, None, visitor.0, false, None, it.kind.descr());
|
|
}
|
|
}
|
|
|
|
hir::ItemKind::Fn(..) => {
|
|
tcx.ensure().generics_of(def_id);
|
|
tcx.ensure().type_of(def_id);
|
|
tcx.ensure().predicates_of(def_id);
|
|
tcx.ensure().fn_sig(def_id);
|
|
tcx.ensure().codegen_fn_attrs(def_id);
|
|
}
|
|
}
|
|
}
|
|
|
|
fn lower_trait_item(tcx: TyCtxt<'_>, trait_item_id: hir::TraitItemId) {
|
|
let trait_item = tcx.hir().trait_item(trait_item_id);
|
|
let def_id = trait_item_id.owner_id;
|
|
tcx.ensure().generics_of(def_id);
|
|
|
|
match trait_item.kind {
|
|
hir::TraitItemKind::Fn(..) => {
|
|
tcx.ensure().codegen_fn_attrs(def_id);
|
|
tcx.ensure().type_of(def_id);
|
|
tcx.ensure().fn_sig(def_id);
|
|
}
|
|
|
|
hir::TraitItemKind::Const(ty, body_id) => {
|
|
tcx.ensure().type_of(def_id);
|
|
if !tcx.dcx().has_stashed_diagnostic(ty.span, StashKey::ItemNoType)
|
|
&& !(ty.is_suggestable_infer_ty() && body_id.is_some())
|
|
{
|
|
// Account for `const C: _;`.
|
|
let mut visitor = HirPlaceholderCollector::default();
|
|
visitor.visit_trait_item(trait_item);
|
|
placeholder_type_error(tcx, None, visitor.0, false, None, "associated constant");
|
|
}
|
|
}
|
|
|
|
hir::TraitItemKind::Type(_, Some(_)) => {
|
|
tcx.ensure().item_bounds(def_id);
|
|
tcx.ensure().item_super_predicates(def_id);
|
|
tcx.ensure().type_of(def_id);
|
|
// Account for `type T = _;`.
|
|
let mut visitor = HirPlaceholderCollector::default();
|
|
visitor.visit_trait_item(trait_item);
|
|
placeholder_type_error(tcx, None, visitor.0, false, None, "associated type");
|
|
}
|
|
|
|
hir::TraitItemKind::Type(_, None) => {
|
|
tcx.ensure().item_bounds(def_id);
|
|
tcx.ensure().item_super_predicates(def_id);
|
|
// #74612: Visit and try to find bad placeholders
|
|
// even if there is no concrete type.
|
|
let mut visitor = HirPlaceholderCollector::default();
|
|
visitor.visit_trait_item(trait_item);
|
|
|
|
placeholder_type_error(tcx, None, visitor.0, false, None, "associated type");
|
|
}
|
|
};
|
|
|
|
tcx.ensure().predicates_of(def_id);
|
|
}
|
|
|
|
fn lower_impl_item(tcx: TyCtxt<'_>, impl_item_id: hir::ImplItemId) {
|
|
let def_id = impl_item_id.owner_id;
|
|
tcx.ensure().generics_of(def_id);
|
|
tcx.ensure().type_of(def_id);
|
|
tcx.ensure().predicates_of(def_id);
|
|
let impl_item = tcx.hir().impl_item(impl_item_id);
|
|
match impl_item.kind {
|
|
hir::ImplItemKind::Fn(..) => {
|
|
tcx.ensure().codegen_fn_attrs(def_id);
|
|
tcx.ensure().fn_sig(def_id);
|
|
}
|
|
hir::ImplItemKind::Type(_) => {
|
|
// Account for `type T = _;`
|
|
let mut visitor = HirPlaceholderCollector::default();
|
|
visitor.visit_impl_item(impl_item);
|
|
|
|
placeholder_type_error(tcx, None, visitor.0, false, None, "associated type");
|
|
}
|
|
hir::ImplItemKind::Const(ty, _) => {
|
|
// Account for `const T: _ = ..;`
|
|
if !ty.is_suggestable_infer_ty() {
|
|
let mut visitor = HirPlaceholderCollector::default();
|
|
visitor.visit_impl_item(impl_item);
|
|
placeholder_type_error(tcx, None, visitor.0, false, None, "associated constant");
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
fn lower_variant_ctor(tcx: TyCtxt<'_>, def_id: LocalDefId) {
|
|
tcx.ensure().generics_of(def_id);
|
|
tcx.ensure().type_of(def_id);
|
|
tcx.ensure().predicates_of(def_id);
|
|
}
|
|
|
|
fn lower_enum_variant_types(tcx: TyCtxt<'_>, def_id: DefId) {
|
|
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 def.variants() {
|
|
let wrapped_discr = prev_discr.map_or(initial, |d| d.wrap_incr(tcx));
|
|
prev_discr = Some(
|
|
if let ty::VariantDiscr::Explicit(const_def_id) = variant.discr {
|
|
def.eval_explicit_discr(tcx, const_def_id).ok()
|
|
} else if let Some(discr) = repr_type.disr_incr(tcx, prev_discr) {
|
|
Some(discr)
|
|
} else {
|
|
let span = tcx.def_span(variant.def_id);
|
|
tcx.dcx().emit_err(errors::EnumDiscriminantOverflowed {
|
|
span,
|
|
discr: prev_discr.unwrap().to_string(),
|
|
item_name: tcx.item_name(variant.def_id),
|
|
wrapped_discr: wrapped_discr.to_string(),
|
|
});
|
|
None
|
|
}
|
|
.unwrap_or(wrapped_discr),
|
|
);
|
|
|
|
for f in &variant.fields {
|
|
tcx.ensure().generics_of(f.did);
|
|
tcx.ensure().type_of(f.did);
|
|
tcx.ensure().predicates_of(f.did);
|
|
}
|
|
|
|
// Lower the ctor, if any. This also registers the variant as an item.
|
|
if let Some(ctor_def_id) = variant.ctor_def_id() {
|
|
lower_variant_ctor(tcx, ctor_def_id.expect_local());
|
|
}
|
|
}
|
|
}
|
|
|
|
fn find_field(tcx: TyCtxt<'_>, (def_id, ident): (DefId, Ident)) -> Option<FieldIdx> {
|
|
let adt = tcx.adt_def(def_id);
|
|
if adt.is_enum() {
|
|
return None;
|
|
}
|
|
|
|
adt.non_enum_variant().fields.iter_enumerated().find_map(|(idx, field)| {
|
|
if field.is_unnamed() {
|
|
let field_ty = tcx.type_of(field.did).instantiate_identity();
|
|
let adt_def = field_ty.ty_adt_def().expect("expect Adt for unnamed field");
|
|
tcx.find_field((adt_def.did(), ident)).map(|_| idx)
|
|
} else {
|
|
(field.ident(tcx).normalize_to_macros_2_0() == ident).then_some(idx)
|
|
}
|
|
})
|
|
}
|
|
|
|
#[derive(Clone, Copy)]
|
|
struct NestedSpan {
|
|
span: Span,
|
|
nested_field_span: Span,
|
|
}
|
|
|
|
impl NestedSpan {
|
|
fn to_field_already_declared_nested_help(&self) -> errors::FieldAlreadyDeclaredNestedHelp {
|
|
errors::FieldAlreadyDeclaredNestedHelp { span: self.span }
|
|
}
|
|
}
|
|
|
|
#[derive(Clone, Copy)]
|
|
enum FieldDeclSpan {
|
|
NotNested(Span),
|
|
Nested(NestedSpan),
|
|
}
|
|
|
|
impl From<Span> for FieldDeclSpan {
|
|
fn from(span: Span) -> Self {
|
|
Self::NotNested(span)
|
|
}
|
|
}
|
|
|
|
impl From<NestedSpan> for FieldDeclSpan {
|
|
fn from(span: NestedSpan) -> Self {
|
|
Self::Nested(span)
|
|
}
|
|
}
|
|
|
|
struct FieldUniquenessCheckContext<'tcx> {
|
|
tcx: TyCtxt<'tcx>,
|
|
seen_fields: FxIndexMap<Ident, FieldDeclSpan>,
|
|
}
|
|
|
|
impl<'tcx> FieldUniquenessCheckContext<'tcx> {
|
|
fn new(tcx: TyCtxt<'tcx>) -> Self {
|
|
Self { tcx, seen_fields: FxIndexMap::default() }
|
|
}
|
|
|
|
/// Check if a given field `ident` declared at `field_decl` has been declared elsewhere before.
|
|
fn check_field_decl(&mut self, ident: Ident, field_decl: FieldDeclSpan) {
|
|
use FieldDeclSpan::*;
|
|
let field_name = ident.name;
|
|
let ident = ident.normalize_to_macros_2_0();
|
|
match (field_decl, self.seen_fields.get(&ident).copied()) {
|
|
(NotNested(span), Some(NotNested(prev_span))) => {
|
|
self.tcx.dcx().emit_err(errors::FieldAlreadyDeclared::NotNested {
|
|
field_name,
|
|
span,
|
|
prev_span,
|
|
});
|
|
}
|
|
(NotNested(span), Some(Nested(prev))) => {
|
|
self.tcx.dcx().emit_err(errors::FieldAlreadyDeclared::PreviousNested {
|
|
field_name,
|
|
span,
|
|
prev_span: prev.span,
|
|
prev_nested_field_span: prev.nested_field_span,
|
|
prev_help: prev.to_field_already_declared_nested_help(),
|
|
});
|
|
}
|
|
(
|
|
Nested(current @ NestedSpan { span, nested_field_span, .. }),
|
|
Some(NotNested(prev_span)),
|
|
) => {
|
|
self.tcx.dcx().emit_err(errors::FieldAlreadyDeclared::CurrentNested {
|
|
field_name,
|
|
span,
|
|
nested_field_span,
|
|
help: current.to_field_already_declared_nested_help(),
|
|
prev_span,
|
|
});
|
|
}
|
|
(Nested(current @ NestedSpan { span, nested_field_span }), Some(Nested(prev))) => {
|
|
self.tcx.dcx().emit_err(errors::FieldAlreadyDeclared::BothNested {
|
|
field_name,
|
|
span,
|
|
nested_field_span,
|
|
help: current.to_field_already_declared_nested_help(),
|
|
prev_span: prev.span,
|
|
prev_nested_field_span: prev.nested_field_span,
|
|
prev_help: prev.to_field_already_declared_nested_help(),
|
|
});
|
|
}
|
|
(field_decl, None) => {
|
|
self.seen_fields.insert(ident, field_decl);
|
|
}
|
|
}
|
|
}
|
|
|
|
/// Check the uniqueness of fields across adt where there are
|
|
/// nested fields imported from an unnamed field.
|
|
fn check_field_in_nested_adt(&mut self, adt_def: ty::AdtDef<'_>, unnamed_field_span: Span) {
|
|
for field in adt_def.all_fields() {
|
|
if field.is_unnamed() {
|
|
// Here we don't care about the generic parameters, so `instantiate_identity` is enough.
|
|
match self.tcx.type_of(field.did).instantiate_identity().kind() {
|
|
ty::Adt(adt_def, _) => {
|
|
self.check_field_in_nested_adt(*adt_def, unnamed_field_span);
|
|
}
|
|
ty_kind => span_bug!(
|
|
self.tcx.def_span(field.did),
|
|
"Unexpected TyKind in FieldUniquenessCheckContext::check_field_in_nested_adt(): {ty_kind:?}"
|
|
),
|
|
}
|
|
} else {
|
|
self.check_field_decl(
|
|
field.ident(self.tcx),
|
|
NestedSpan {
|
|
span: unnamed_field_span,
|
|
nested_field_span: self.tcx.def_span(field.did),
|
|
}
|
|
.into(),
|
|
);
|
|
}
|
|
}
|
|
}
|
|
|
|
/// Check the uniqueness of fields in a struct variant, and recursively
|
|
/// check the nested fields if it is an unnamed field with type of an
|
|
/// annoymous adt.
|
|
fn check_field(&mut self, field: &hir::FieldDef<'_>) {
|
|
if field.ident.name != kw::Underscore {
|
|
self.check_field_decl(field.ident, field.span.into());
|
|
return;
|
|
}
|
|
match &field.ty.kind {
|
|
hir::TyKind::AnonAdt(item_id) => {
|
|
match &self.tcx.hir_node(item_id.hir_id()).expect_item().kind {
|
|
hir::ItemKind::Struct(variant_data, ..)
|
|
| hir::ItemKind::Union(variant_data, ..) => {
|
|
variant_data.fields().iter().for_each(|f| self.check_field(f));
|
|
}
|
|
item_kind => span_bug!(
|
|
field.ty.span,
|
|
"Unexpected ItemKind in FieldUniquenessCheckContext::check_field(): {item_kind:?}"
|
|
),
|
|
}
|
|
}
|
|
hir::TyKind::Path(hir::QPath::Resolved(_, hir::Path { res, .. })) => {
|
|
// If this is a direct path to an ADT, we can check it
|
|
// If this is a type alias or non-ADT, `check_unnamed_fields` should verify it
|
|
if let Some(def_id) = res.opt_def_id()
|
|
&& let Some(local) = def_id.as_local()
|
|
&& let Node::Item(item) = self.tcx.hir_node_by_def_id(local)
|
|
&& item.is_adt()
|
|
{
|
|
self.check_field_in_nested_adt(self.tcx.adt_def(def_id), field.span);
|
|
}
|
|
}
|
|
// Abort due to errors (there must be an error if an unnamed field
|
|
// has any type kind other than an anonymous adt or a named adt)
|
|
ty_kind => {
|
|
self.tcx.dcx().span_delayed_bug(
|
|
field.ty.span,
|
|
format!("Unexpected TyKind in FieldUniquenessCheckContext::check_field(): {ty_kind:?}"),
|
|
);
|
|
// FIXME: errors during AST validation should abort the compilation before reaching here.
|
|
self.tcx.dcx().abort_if_errors();
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
fn lower_variant(
|
|
tcx: TyCtxt<'_>,
|
|
variant_did: Option<LocalDefId>,
|
|
ident: Ident,
|
|
discr: ty::VariantDiscr,
|
|
def: &hir::VariantData<'_>,
|
|
adt_kind: ty::AdtKind,
|
|
parent_did: LocalDefId,
|
|
is_anonymous: bool,
|
|
) -> ty::VariantDef {
|
|
let mut has_unnamed_fields = false;
|
|
let mut field_uniqueness_check_ctx = FieldUniquenessCheckContext::new(tcx);
|
|
let fields = def
|
|
.fields()
|
|
.iter()
|
|
.inspect(|f| {
|
|
has_unnamed_fields |= f.ident.name == kw::Underscore;
|
|
// We only check named ADT here because anonymous ADTs are checked inside
|
|
// the named ADT in which they are defined.
|
|
if !is_anonymous {
|
|
field_uniqueness_check_ctx.check_field(f);
|
|
}
|
|
})
|
|
.map(|f| ty::FieldDef {
|
|
did: f.def_id.to_def_id(),
|
|
name: f.ident.name,
|
|
vis: tcx.visibility(f.def_id),
|
|
})
|
|
.collect();
|
|
let recovered = matches!(def, hir::VariantData::Struct { recovered: Recovered::Yes(_), .. });
|
|
ty::VariantDef::new(
|
|
ident.name,
|
|
variant_did.map(LocalDefId::to_def_id),
|
|
def.ctor().map(|(kind, _, def_id)| (kind, def_id.to_def_id())),
|
|
discr,
|
|
fields,
|
|
adt_kind,
|
|
parent_did.to_def_id(),
|
|
recovered,
|
|
adt_kind == AdtKind::Struct && tcx.has_attr(parent_did, sym::non_exhaustive)
|
|
|| variant_did
|
|
.is_some_and(|variant_did| tcx.has_attr(variant_did, sym::non_exhaustive)),
|
|
has_unnamed_fields,
|
|
)
|
|
}
|
|
|
|
fn adt_def(tcx: TyCtxt<'_>, def_id: LocalDefId) -> ty::AdtDef<'_> {
|
|
use rustc_hir::*;
|
|
|
|
let Node::Item(item) = tcx.hir_node_by_def_id(def_id) else {
|
|
bug!("expected ADT to be an item");
|
|
};
|
|
|
|
let is_anonymous = item.ident.name == kw::Empty;
|
|
let repr = if is_anonymous {
|
|
let parent = tcx.local_parent(def_id);
|
|
if let Node::Item(item) = tcx.hir_node_by_def_id(parent)
|
|
&& item.is_struct_or_union()
|
|
{
|
|
tcx.adt_def(parent).repr()
|
|
} else {
|
|
tcx.dcx().span_delayed_bug(item.span, "anonymous field inside non struct/union");
|
|
ty::ReprOptions::default()
|
|
}
|
|
} else {
|
|
tcx.repr_options_of_def(def_id)
|
|
};
|
|
let (kind, variants) = match &item.kind {
|
|
ItemKind::Enum(def, _) => {
|
|
let mut distance_from_explicit = 0;
|
|
let variants = def
|
|
.variants
|
|
.iter()
|
|
.map(|v| {
|
|
let discr = if let Some(e) = &v.disr_expr {
|
|
distance_from_explicit = 0;
|
|
ty::VariantDiscr::Explicit(e.def_id.to_def_id())
|
|
} else {
|
|
ty::VariantDiscr::Relative(distance_from_explicit)
|
|
};
|
|
distance_from_explicit += 1;
|
|
|
|
lower_variant(
|
|
tcx,
|
|
Some(v.def_id),
|
|
v.ident,
|
|
discr,
|
|
&v.data,
|
|
AdtKind::Enum,
|
|
def_id,
|
|
is_anonymous,
|
|
)
|
|
})
|
|
.collect();
|
|
|
|
(AdtKind::Enum, variants)
|
|
}
|
|
ItemKind::Struct(def, _) | ItemKind::Union(def, _) => {
|
|
let adt_kind = match item.kind {
|
|
ItemKind::Struct(..) => AdtKind::Struct,
|
|
_ => AdtKind::Union,
|
|
};
|
|
let variants = std::iter::once(lower_variant(
|
|
tcx,
|
|
None,
|
|
item.ident,
|
|
ty::VariantDiscr::Relative(0),
|
|
def,
|
|
adt_kind,
|
|
def_id,
|
|
is_anonymous,
|
|
))
|
|
.collect();
|
|
|
|
(adt_kind, variants)
|
|
}
|
|
_ => bug!("{:?} is not an ADT", item.owner_id.def_id),
|
|
};
|
|
tcx.mk_adt_def(def_id.to_def_id(), kind, variants, repr, is_anonymous)
|
|
}
|
|
|
|
fn trait_def(tcx: TyCtxt<'_>, def_id: LocalDefId) -> ty::TraitDef {
|
|
let item = tcx.hir().expect_item(def_id);
|
|
|
|
let (is_auto, safety, items) = match item.kind {
|
|
hir::ItemKind::Trait(is_auto, safety, .., items) => {
|
|
(is_auto == hir::IsAuto::Yes, safety, items)
|
|
}
|
|
hir::ItemKind::TraitAlias(..) => (false, hir::Safety::Safe, &[][..]),
|
|
_ => 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.dcx().emit_err(errors::ParenSugarAttribute { span: item.span });
|
|
}
|
|
|
|
let is_marker = tcx.has_attr(def_id, sym::marker);
|
|
let rustc_coinductive = tcx.has_attr(def_id, sym::rustc_coinductive);
|
|
|
|
// FIXME: We could probably do way better attribute validation here.
|
|
let mut skip_array_during_method_dispatch = false;
|
|
let mut skip_boxed_slice_during_method_dispatch = false;
|
|
for attr in tcx.get_attrs(def_id, sym::rustc_skip_during_method_dispatch) {
|
|
if let Some(lst) = attr.meta_item_list() {
|
|
for item in lst {
|
|
if let Some(ident) = item.ident() {
|
|
match ident.as_str() {
|
|
"array" => skip_array_during_method_dispatch = true,
|
|
"boxed_slice" => skip_boxed_slice_during_method_dispatch = true,
|
|
_ => (),
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
let specialization_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 must_implement_one_of = tcx
|
|
.get_attr(def_id, sym::rustc_must_implement_one_of)
|
|
// Check that there are at least 2 arguments of `#[rustc_must_implement_one_of]`
|
|
// and that they are all identifiers
|
|
.and_then(|attr| match attr.meta_item_list() {
|
|
Some(items) if items.len() < 2 => {
|
|
tcx.dcx().emit_err(errors::MustImplementOneOfAttribute { span: attr.span });
|
|
|
|
None
|
|
}
|
|
Some(items) => items
|
|
.into_iter()
|
|
.map(|item| item.ident().ok_or(item.span()))
|
|
.collect::<Result<Box<[_]>, _>>()
|
|
.map_err(|span| {
|
|
tcx.dcx().emit_err(errors::MustBeNameOfAssociatedFunction { span });
|
|
})
|
|
.ok()
|
|
.zip(Some(attr.span)),
|
|
// Error is reported by `rustc_attr!`
|
|
None => None,
|
|
})
|
|
// Check that all arguments of `#[rustc_must_implement_one_of]` reference
|
|
// functions in the trait with default implementations
|
|
.and_then(|(list, attr_span)| {
|
|
let errors = list.iter().filter_map(|ident| {
|
|
let item = items.iter().find(|item| item.ident == *ident);
|
|
|
|
match item {
|
|
Some(item) if matches!(item.kind, hir::AssocItemKind::Fn { .. }) => {
|
|
if !tcx.defaultness(item.id.owner_id).has_value() {
|
|
tcx.dcx().emit_err(errors::FunctionNotHaveDefaultImplementation {
|
|
span: item.span,
|
|
note_span: attr_span,
|
|
});
|
|
|
|
return Some(());
|
|
}
|
|
|
|
return None;
|
|
}
|
|
Some(item) => {
|
|
tcx.dcx().emit_err(errors::MustImplementNotFunction {
|
|
span: item.span,
|
|
span_note: errors::MustImplementNotFunctionSpanNote { span: attr_span },
|
|
note: errors::MustImplementNotFunctionNote {},
|
|
});
|
|
}
|
|
None => {
|
|
tcx.dcx().emit_err(errors::FunctionNotFoundInTrait { span: ident.span });
|
|
}
|
|
}
|
|
|
|
Some(())
|
|
});
|
|
|
|
(errors.count() == 0).then_some(list)
|
|
})
|
|
// Check for duplicates
|
|
.and_then(|list| {
|
|
let mut set: UnordMap<Symbol, Span> = Default::default();
|
|
let mut no_dups = true;
|
|
|
|
for ident in &*list {
|
|
if let Some(dup) = set.insert(ident.name, ident.span) {
|
|
tcx.dcx()
|
|
.emit_err(errors::FunctionNamesDuplicated { spans: vec![dup, ident.span] });
|
|
|
|
no_dups = false;
|
|
}
|
|
}
|
|
|
|
no_dups.then_some(list)
|
|
});
|
|
|
|
let mut deny_explicit_impl = false;
|
|
let mut implement_via_object = true;
|
|
if let Some(attr) = tcx.get_attr(def_id, sym::rustc_deny_explicit_impl) {
|
|
deny_explicit_impl = true;
|
|
let mut seen_attr = false;
|
|
for meta in attr.meta_item_list().iter().flatten() {
|
|
if let Some(meta) = meta.meta_item()
|
|
&& meta.name_or_empty() == sym::implement_via_object
|
|
&& let Some(lit) = meta.name_value_literal()
|
|
{
|
|
if seen_attr {
|
|
tcx.dcx().span_err(meta.span, "duplicated `implement_via_object` meta item");
|
|
}
|
|
seen_attr = true;
|
|
|
|
match lit.symbol {
|
|
kw::True => {
|
|
implement_via_object = true;
|
|
}
|
|
kw::False => {
|
|
implement_via_object = false;
|
|
}
|
|
_ => {
|
|
tcx.dcx().span_err(
|
|
meta.span,
|
|
format!(
|
|
"unknown literal passed to `implement_via_object` attribute: {}",
|
|
lit.symbol
|
|
),
|
|
);
|
|
}
|
|
}
|
|
} else {
|
|
tcx.dcx().span_err(
|
|
meta.span(),
|
|
format!("unknown meta item passed to `rustc_deny_explicit_impl` {meta:?}"),
|
|
);
|
|
}
|
|
}
|
|
if !seen_attr {
|
|
tcx.dcx().span_err(attr.span, "missing `implement_via_object` meta item");
|
|
}
|
|
}
|
|
|
|
ty::TraitDef {
|
|
def_id: def_id.to_def_id(),
|
|
safety,
|
|
paren_sugar,
|
|
has_auto_impl: is_auto,
|
|
is_marker,
|
|
is_coinductive: rustc_coinductive || is_auto,
|
|
skip_array_during_method_dispatch,
|
|
skip_boxed_slice_during_method_dispatch,
|
|
specialization_kind,
|
|
must_implement_one_of,
|
|
implement_via_object,
|
|
deny_explicit_impl,
|
|
}
|
|
}
|
|
|
|
#[instrument(level = "debug", skip(tcx))]
|
|
fn fn_sig(tcx: TyCtxt<'_>, def_id: LocalDefId) -> ty::EarlyBinder<'_, ty::PolyFnSig<'_>> {
|
|
use rustc_hir::Node::*;
|
|
use rustc_hir::*;
|
|
|
|
let hir_id = tcx.local_def_id_to_hir_id(def_id);
|
|
|
|
let icx = ItemCtxt::new(tcx, def_id);
|
|
|
|
let output = match tcx.hir_node(hir_id) {
|
|
TraitItem(hir::TraitItem {
|
|
kind: TraitItemKind::Fn(sig, TraitFn::Provided(_)),
|
|
generics,
|
|
..
|
|
})
|
|
| Item(hir::Item { kind: ItemKind::Fn(sig, generics, _), .. }) => {
|
|
infer_return_ty_for_fn_sig(tcx, sig, generics, def_id, &icx)
|
|
}
|
|
|
|
ImplItem(hir::ImplItem { kind: ImplItemKind::Fn(sig, _), generics, .. }) => {
|
|
// Do not try to infer the return type for a impl method coming from a trait
|
|
if let Item(hir::Item { kind: ItemKind::Impl(i), .. }) = tcx.parent_hir_node(hir_id)
|
|
&& i.of_trait.is_some()
|
|
{
|
|
icx.lowerer().lower_fn_ty(
|
|
hir_id,
|
|
sig.header.safety,
|
|
sig.header.abi,
|
|
sig.decl,
|
|
Some(generics),
|
|
None,
|
|
)
|
|
} else {
|
|
infer_return_ty_for_fn_sig(tcx, sig, generics, def_id, &icx)
|
|
}
|
|
}
|
|
|
|
TraitItem(hir::TraitItem {
|
|
kind: TraitItemKind::Fn(FnSig { header, decl, span: _ }, _),
|
|
generics,
|
|
..
|
|
}) => {
|
|
icx.lowerer().lower_fn_ty(hir_id, header.safety, header.abi, decl, Some(generics), None)
|
|
}
|
|
|
|
ForeignItem(&hir::ForeignItem {
|
|
kind: ForeignItemKind::Fn(fn_decl, _, _, safety), ..
|
|
}) => {
|
|
let abi = tcx.hir().get_foreign_abi(hir_id);
|
|
compute_sig_of_foreign_fn_decl(tcx, def_id, fn_decl, abi, safety)
|
|
}
|
|
|
|
Ctor(data) | Variant(hir::Variant { data, .. }) if data.ctor().is_some() => {
|
|
let adt_def_id = tcx.hir().get_parent_item(hir_id).def_id.to_def_id();
|
|
let ty = tcx.type_of(adt_def_id).instantiate_identity();
|
|
let inputs = data.fields().iter().map(|f| tcx.type_of(f.def_id).instantiate_identity());
|
|
// constructors for structs with `layout_scalar_valid_range` are unsafe to call
|
|
let safety = match tcx.layout_scalar_valid_range(adt_def_id) {
|
|
(Bound::Unbounded, Bound::Unbounded) => hir::Safety::Safe,
|
|
_ => hir::Safety::Unsafe,
|
|
};
|
|
ty::Binder::dummy(tcx.mk_fn_sig(inputs, ty, false, safety, 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 `ClosureArgs`.
|
|
//
|
|
// To get the signature of a closure, you should use the
|
|
// `sig` method on the `ClosureArgs`:
|
|
//
|
|
// args.as_closure().sig(def_id, tcx)
|
|
bug!("to get the signature of a closure, use `args.as_closure().sig()` not `fn_sig()`",);
|
|
}
|
|
|
|
x => {
|
|
bug!("unexpected sort of node in fn_sig(): {:?}", x);
|
|
}
|
|
};
|
|
ty::EarlyBinder::bind(output)
|
|
}
|
|
|
|
fn infer_return_ty_for_fn_sig<'tcx>(
|
|
tcx: TyCtxt<'tcx>,
|
|
sig: &hir::FnSig<'tcx>,
|
|
generics: &hir::Generics<'_>,
|
|
def_id: LocalDefId,
|
|
icx: &ItemCtxt<'tcx>,
|
|
) -> ty::PolyFnSig<'tcx> {
|
|
let hir_id = tcx.local_def_id_to_hir_id(def_id);
|
|
|
|
match sig.decl.output.get_infer_ret_ty() {
|
|
Some(ty) => {
|
|
let fn_sig = tcx.typeck(def_id).liberated_fn_sigs()[hir_id];
|
|
// Typeck doesn't expect erased regions to be returned from `type_of`.
|
|
let fn_sig = tcx.fold_regions(fn_sig, |r, _| match *r {
|
|
ty::ReErased => tcx.lifetimes.re_static,
|
|
_ => r,
|
|
});
|
|
|
|
let mut visitor = HirPlaceholderCollector::default();
|
|
visitor.visit_ty(ty);
|
|
|
|
let mut diag = bad_placeholder(tcx, visitor.0, "return type");
|
|
let ret_ty = fn_sig.output();
|
|
// Don't leak types into signatures unless they're nameable!
|
|
// For example, if a function returns itself, we don't want that
|
|
// recursive function definition to leak out into the fn sig.
|
|
let mut recovered_ret_ty = None;
|
|
|
|
if let Some(suggestable_ret_ty) = ret_ty.make_suggestable(tcx, false, None) {
|
|
diag.span_suggestion(
|
|
ty.span,
|
|
"replace with the correct return type",
|
|
suggestable_ret_ty,
|
|
Applicability::MachineApplicable,
|
|
);
|
|
recovered_ret_ty = Some(suggestable_ret_ty);
|
|
} else if let Some(sugg) =
|
|
suggest_impl_trait(&tcx.infer_ctxt().build(), tcx.param_env(def_id), ret_ty)
|
|
{
|
|
diag.span_suggestion(
|
|
ty.span,
|
|
"replace with an appropriate return type",
|
|
sugg,
|
|
Applicability::MachineApplicable,
|
|
);
|
|
} else if ret_ty.is_closure() {
|
|
diag.help("consider using an `Fn`, `FnMut`, or `FnOnce` trait bound");
|
|
}
|
|
// Also note how `Fn` traits work just in case!
|
|
if ret_ty.is_closure() {
|
|
diag.note(
|
|
"for more information on `Fn` traits and closure types, see \
|
|
https://doc.rust-lang.org/book/ch13-01-closures.html",
|
|
);
|
|
}
|
|
|
|
let guar = diag.emit();
|
|
ty::Binder::dummy(tcx.mk_fn_sig(
|
|
fn_sig.inputs().iter().copied(),
|
|
recovered_ret_ty.unwrap_or_else(|| Ty::new_error(tcx, guar)),
|
|
fn_sig.c_variadic,
|
|
fn_sig.safety,
|
|
fn_sig.abi,
|
|
))
|
|
}
|
|
None => icx.lowerer().lower_fn_ty(
|
|
hir_id,
|
|
sig.header.safety,
|
|
sig.header.abi,
|
|
sig.decl,
|
|
Some(generics),
|
|
None,
|
|
),
|
|
}
|
|
}
|
|
|
|
pub fn suggest_impl_trait<'tcx>(
|
|
infcx: &InferCtxt<'tcx>,
|
|
param_env: ty::ParamEnv<'tcx>,
|
|
ret_ty: Ty<'tcx>,
|
|
) -> Option<String> {
|
|
let format_as_assoc: fn(_, _, _, _, _) -> _ =
|
|
|tcx: TyCtxt<'tcx>,
|
|
_: ty::GenericArgsRef<'tcx>,
|
|
trait_def_id: DefId,
|
|
assoc_item_def_id: DefId,
|
|
item_ty: Ty<'tcx>| {
|
|
let trait_name = tcx.item_name(trait_def_id);
|
|
let assoc_name = tcx.item_name(assoc_item_def_id);
|
|
Some(format!("impl {trait_name}<{assoc_name} = {item_ty}>"))
|
|
};
|
|
let format_as_parenthesized: fn(_, _, _, _, _) -> _ =
|
|
|tcx: TyCtxt<'tcx>,
|
|
args: ty::GenericArgsRef<'tcx>,
|
|
trait_def_id: DefId,
|
|
_: DefId,
|
|
item_ty: Ty<'tcx>| {
|
|
let trait_name = tcx.item_name(trait_def_id);
|
|
let args_tuple = args.type_at(1);
|
|
let ty::Tuple(types) = *args_tuple.kind() else {
|
|
return None;
|
|
};
|
|
let types = types.make_suggestable(tcx, false, None)?;
|
|
let maybe_ret =
|
|
if item_ty.is_unit() { String::new() } else { format!(" -> {item_ty}") };
|
|
Some(format!(
|
|
"impl {trait_name}({}){maybe_ret}",
|
|
types.iter().map(|ty| ty.to_string()).collect::<Vec<_>>().join(", ")
|
|
))
|
|
};
|
|
|
|
for (trait_def_id, assoc_item_def_id, formatter) in [
|
|
(
|
|
infcx.tcx.get_diagnostic_item(sym::Iterator),
|
|
infcx.tcx.get_diagnostic_item(sym::IteratorItem),
|
|
format_as_assoc,
|
|
),
|
|
(
|
|
infcx.tcx.lang_items().future_trait(),
|
|
infcx.tcx.lang_items().future_output(),
|
|
format_as_assoc,
|
|
),
|
|
(
|
|
infcx.tcx.lang_items().fn_trait(),
|
|
infcx.tcx.lang_items().fn_once_output(),
|
|
format_as_parenthesized,
|
|
),
|
|
(
|
|
infcx.tcx.lang_items().fn_mut_trait(),
|
|
infcx.tcx.lang_items().fn_once_output(),
|
|
format_as_parenthesized,
|
|
),
|
|
(
|
|
infcx.tcx.lang_items().fn_once_trait(),
|
|
infcx.tcx.lang_items().fn_once_output(),
|
|
format_as_parenthesized,
|
|
),
|
|
] {
|
|
let Some(trait_def_id) = trait_def_id else {
|
|
continue;
|
|
};
|
|
let Some(assoc_item_def_id) = assoc_item_def_id else {
|
|
continue;
|
|
};
|
|
if infcx.tcx.def_kind(assoc_item_def_id) != DefKind::AssocTy {
|
|
continue;
|
|
}
|
|
let sugg = infcx.probe(|_| {
|
|
let args = ty::GenericArgs::for_item(infcx.tcx, trait_def_id, |param, _| {
|
|
if param.index == 0 { ret_ty.into() } else { infcx.var_for_def(DUMMY_SP, param) }
|
|
});
|
|
if !infcx
|
|
.type_implements_trait(trait_def_id, args, param_env)
|
|
.must_apply_modulo_regions()
|
|
{
|
|
return None;
|
|
}
|
|
let ocx = ObligationCtxt::new(&infcx);
|
|
let item_ty = ocx.normalize(
|
|
&ObligationCause::dummy(),
|
|
param_env,
|
|
Ty::new_projection(infcx.tcx, assoc_item_def_id, args),
|
|
);
|
|
// FIXME(compiler-errors): We may benefit from resolving regions here.
|
|
if ocx.select_where_possible().is_empty()
|
|
&& let item_ty = infcx.resolve_vars_if_possible(item_ty)
|
|
&& let Some(item_ty) = item_ty.make_suggestable(infcx.tcx, false, None)
|
|
&& let Some(sugg) = formatter(
|
|
infcx.tcx,
|
|
infcx.resolve_vars_if_possible(args),
|
|
trait_def_id,
|
|
assoc_item_def_id,
|
|
item_ty,
|
|
)
|
|
{
|
|
return Some(sugg);
|
|
}
|
|
|
|
None
|
|
});
|
|
|
|
if sugg.is_some() {
|
|
return sugg;
|
|
}
|
|
}
|
|
None
|
|
}
|
|
|
|
fn impl_trait_header(tcx: TyCtxt<'_>, def_id: LocalDefId) -> Option<ty::ImplTraitHeader<'_>> {
|
|
let icx = ItemCtxt::new(tcx, def_id);
|
|
let item = tcx.hir().expect_item(def_id);
|
|
let impl_ = item.expect_impl();
|
|
impl_
|
|
.of_trait
|
|
.as_ref()
|
|
.map(|hir_trait_ref| {
|
|
let self_ty = tcx.type_of(def_id).instantiate_identity();
|
|
|
|
let trait_ref = if let Some(ErrorGuaranteed { .. }) = check_impl_constness(
|
|
tcx,
|
|
tcx.is_const_trait_impl_raw(def_id.to_def_id()),
|
|
hir_trait_ref,
|
|
) {
|
|
// we have a const impl, but for a trait without `#[const_trait]`, so
|
|
// without the host param. If we continue with the HIR trait ref, we get
|
|
// ICEs for generic arg count mismatch. We do a little HIR editing to
|
|
// make HIR ty lowering happy.
|
|
let mut path_segments = hir_trait_ref.path.segments.to_vec();
|
|
let last_segment = path_segments.len() - 1;
|
|
let mut args = *path_segments[last_segment].args();
|
|
let last_arg = args.args.len() - 1;
|
|
assert!(matches!(args.args[last_arg], hir::GenericArg::Const(anon_const) if anon_const.is_desugared_from_effects));
|
|
args.args = &args.args[..args.args.len() - 1];
|
|
path_segments[last_segment].args = Some(tcx.hir_arena.alloc(args));
|
|
let path = hir::Path {
|
|
span: hir_trait_ref.path.span,
|
|
res: hir_trait_ref.path.res,
|
|
segments: tcx.hir_arena.alloc_slice(&path_segments),
|
|
};
|
|
let trait_ref = tcx.hir_arena.alloc(hir::TraitRef { path: tcx.hir_arena.alloc(path), hir_ref_id: hir_trait_ref.hir_ref_id });
|
|
icx.lowerer().lower_impl_trait_ref(trait_ref, self_ty)
|
|
} else {
|
|
icx.lowerer().lower_impl_trait_ref(hir_trait_ref, self_ty)
|
|
};
|
|
ty::ImplTraitHeader {
|
|
trait_ref: ty::EarlyBinder::bind(trait_ref),
|
|
safety: impl_.safety,
|
|
polarity: polarity_of_impl(tcx, def_id, impl_, item.span)
|
|
}
|
|
})
|
|
}
|
|
|
|
fn check_impl_constness(
|
|
tcx: TyCtxt<'_>,
|
|
is_const: bool,
|
|
hir_trait_ref: &hir::TraitRef<'_>,
|
|
) -> Option<ErrorGuaranteed> {
|
|
if !is_const {
|
|
return None;
|
|
}
|
|
|
|
let trait_def_id = hir_trait_ref.trait_def_id()?;
|
|
if tcx.has_attr(trait_def_id, sym::const_trait) {
|
|
return None;
|
|
}
|
|
|
|
let trait_name = tcx.item_name(trait_def_id).to_string();
|
|
Some(tcx.dcx().emit_err(errors::ConstImplForNonConstTrait {
|
|
trait_ref_span: hir_trait_ref.path.span,
|
|
trait_name,
|
|
local_trait_span:
|
|
trait_def_id.as_local().map(|_| tcx.def_span(trait_def_id).shrink_to_lo()),
|
|
marking: (),
|
|
adding: (),
|
|
}))
|
|
}
|
|
|
|
fn polarity_of_impl(
|
|
tcx: TyCtxt<'_>,
|
|
def_id: LocalDefId,
|
|
impl_: &hir::Impl<'_>,
|
|
span: Span,
|
|
) -> ty::ImplPolarity {
|
|
let is_rustc_reservation = tcx.has_attr(def_id, sym::rustc_reservation_impl);
|
|
match &impl_ {
|
|
hir::Impl { polarity: hir::ImplPolarity::Negative(span), of_trait, .. } => {
|
|
if is_rustc_reservation {
|
|
let span = span.to(of_trait.as_ref().map_or(*span, |t| t.path.span));
|
|
tcx.dcx().span_err(span, "reservation impls can't be negative");
|
|
}
|
|
ty::ImplPolarity::Negative
|
|
}
|
|
hir::Impl { polarity: hir::ImplPolarity::Positive, of_trait: None, .. } => {
|
|
if is_rustc_reservation {
|
|
tcx.dcx().span_err(span, "reservation impls can't be inherent");
|
|
}
|
|
ty::ImplPolarity::Positive
|
|
}
|
|
hir::Impl { polarity: hir::ImplPolarity::Positive, of_trait: Some(_), .. } => {
|
|
if is_rustc_reservation {
|
|
ty::ImplPolarity::Reservation
|
|
} else {
|
|
ty::ImplPolarity::Positive
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
/// 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.
|
|
#[instrument(level = "debug", skip(tcx))]
|
|
fn predicates_defined_on(tcx: TyCtxt<'_>, def_id: DefId) -> ty::GenericPredicates<'_> {
|
|
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,
|
|
);
|
|
let inferred_outlives_iter =
|
|
inferred_outlives.iter().map(|(clause, span)| ((*clause).upcast(tcx), *span));
|
|
if result.predicates.is_empty() {
|
|
result.predicates = tcx.arena.alloc_from_iter(inferred_outlives_iter);
|
|
} else {
|
|
result.predicates = tcx.arena.alloc_from_iter(
|
|
result.predicates.into_iter().copied().chain(inferred_outlives_iter),
|
|
);
|
|
}
|
|
}
|
|
|
|
debug!("predicates_defined_on({:?}) = {:?}", def_id, result);
|
|
result
|
|
}
|
|
|
|
fn compute_sig_of_foreign_fn_decl<'tcx>(
|
|
tcx: TyCtxt<'tcx>,
|
|
def_id: LocalDefId,
|
|
decl: &'tcx hir::FnDecl<'tcx>,
|
|
abi: abi::Abi,
|
|
safety: hir::Safety,
|
|
) -> ty::PolyFnSig<'tcx> {
|
|
let safety = if abi == abi::Abi::RustIntrinsic {
|
|
intrinsic_operation_unsafety(tcx, def_id)
|
|
} else {
|
|
safety
|
|
};
|
|
let hir_id = tcx.local_def_id_to_hir_id(def_id);
|
|
let fty =
|
|
ItemCtxt::new(tcx, def_id).lowerer().lower_fn_ty(hir_id, safety, abi, decl, None, None);
|
|
|
|
// 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 && !tcx.features().simd_ffi {
|
|
let check = |hir_ty: &hir::Ty<'_>, ty: Ty<'_>| {
|
|
if ty.is_simd() {
|
|
let snip = tcx
|
|
.sess
|
|
.source_map()
|
|
.span_to_snippet(hir_ty.span)
|
|
.map_or_else(|_| String::new(), |s| format!(" `{s}`"));
|
|
tcx.dcx().emit_err(errors::SIMDFFIHighlyExperimental { span: hir_ty.span, snip });
|
|
}
|
|
};
|
|
for (input, ty) in iter::zip(decl.inputs, fty.inputs().skip_binder()) {
|
|
check(input, *ty)
|
|
}
|
|
if let hir::FnRetTy::Return(ty) = decl.output {
|
|
check(ty, fty.output().skip_binder())
|
|
}
|
|
}
|
|
|
|
fty
|
|
}
|
|
|
|
fn coroutine_kind(tcx: TyCtxt<'_>, def_id: LocalDefId) -> Option<hir::CoroutineKind> {
|
|
match tcx.hir_node_by_def_id(def_id) {
|
|
Node::Expr(&hir::Expr {
|
|
kind:
|
|
hir::ExprKind::Closure(&rustc_hir::Closure {
|
|
kind: hir::ClosureKind::Coroutine(kind),
|
|
..
|
|
}),
|
|
..
|
|
}) => Some(kind),
|
|
_ => None,
|
|
}
|
|
}
|
|
|
|
fn coroutine_for_closure(tcx: TyCtxt<'_>, def_id: LocalDefId) -> DefId {
|
|
let &rustc_hir::Closure { kind: hir::ClosureKind::CoroutineClosure(_), body, .. } =
|
|
tcx.hir_node_by_def_id(def_id).expect_closure()
|
|
else {
|
|
bug!()
|
|
};
|
|
|
|
let &hir::Expr {
|
|
kind:
|
|
hir::ExprKind::Closure(&rustc_hir::Closure {
|
|
def_id,
|
|
kind: hir::ClosureKind::Coroutine(_),
|
|
..
|
|
}),
|
|
..
|
|
} = tcx.hir().body(body).value
|
|
else {
|
|
bug!()
|
|
};
|
|
|
|
def_id.to_def_id()
|
|
}
|
|
|
|
fn is_type_alias_impl_trait<'tcx>(tcx: TyCtxt<'tcx>, def_id: LocalDefId) -> bool {
|
|
match tcx.hir_node_by_def_id(def_id) {
|
|
Node::Item(hir::Item { kind: hir::ItemKind::OpaqueTy(opaque), .. }) => {
|
|
matches!(opaque.origin, hir::OpaqueTyOrigin::TyAlias { .. })
|
|
}
|
|
_ => bug!("tried getting opaque_ty_origin for non-opaque: {:?}", def_id),
|
|
}
|
|
}
|