6713f34ee4
This eliminates all methods on `Map`. Actually removing `Map` will occur in a follow-up PR.
1837 lines
73 KiB
Rust
1837 lines
73 KiB
Rust
use std::cell::LazyCell;
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use std::ops::ControlFlow;
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use rustc_abi::FieldIdx;
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use rustc_attr_parsing::AttributeKind;
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use rustc_attr_parsing::ReprAttr::ReprPacked;
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use rustc_data_structures::unord::{UnordMap, UnordSet};
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use rustc_errors::MultiSpan;
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use rustc_errors::codes::*;
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use rustc_hir::def::{CtorKind, DefKind};
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use rustc_hir::{LangItem, Node, intravisit};
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use rustc_infer::infer::{RegionVariableOrigin, TyCtxtInferExt};
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use rustc_infer::traits::{Obligation, ObligationCauseCode};
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use rustc_lint_defs::builtin::{
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REPR_TRANSPARENT_EXTERNAL_PRIVATE_FIELDS, UNSUPPORTED_FN_PTR_CALLING_CONVENTIONS,
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};
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use rustc_middle::hir::nested_filter;
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use rustc_middle::middle::resolve_bound_vars::ResolvedArg;
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use rustc_middle::middle::stability::EvalResult;
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use rustc_middle::ty::error::TypeErrorToStringExt;
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use rustc_middle::ty::layout::{LayoutError, MAX_SIMD_LANES};
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use rustc_middle::ty::util::{Discr, IntTypeExt};
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use rustc_middle::ty::{
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AdtDef, BottomUpFolder, GenericArgKind, RegionKind, TypeFoldable, TypeSuperVisitable,
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TypeVisitable, TypeVisitableExt, fold_regions,
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};
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use rustc_session::lint::builtin::UNINHABITED_STATIC;
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use rustc_trait_selection::error_reporting::InferCtxtErrorExt;
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use rustc_trait_selection::error_reporting::traits::on_unimplemented::OnUnimplementedDirective;
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use rustc_trait_selection::traits;
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use rustc_trait_selection::traits::query::evaluate_obligation::InferCtxtExt;
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use tracing::{debug, instrument};
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use ty::TypingMode;
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use {rustc_attr_parsing as attr, rustc_hir as hir};
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use super::compare_impl_item::check_type_bounds;
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use super::*;
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pub fn check_abi(tcx: TyCtxt<'_>, span: Span, abi: ExternAbi) {
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if !tcx.sess.target.is_abi_supported(abi) {
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struct_span_code_err!(
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tcx.dcx(),
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span,
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E0570,
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"`{abi}` is not a supported ABI for the current target",
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)
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.emit();
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}
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}
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pub fn check_abi_fn_ptr(tcx: TyCtxt<'_>, hir_id: hir::HirId, span: Span, abi: ExternAbi) {
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if !tcx.sess.target.is_abi_supported(abi) {
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tcx.node_span_lint(UNSUPPORTED_FN_PTR_CALLING_CONVENTIONS, hir_id, span, |lint| {
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lint.primary_message(format!(
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"the calling convention {abi} is not supported on this target"
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));
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});
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}
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}
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fn check_struct(tcx: TyCtxt<'_>, def_id: LocalDefId) {
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let def = tcx.adt_def(def_id);
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let span = tcx.def_span(def_id);
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def.destructor(tcx); // force the destructor to be evaluated
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if def.repr().simd() {
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check_simd(tcx, span, def_id);
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}
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check_transparent(tcx, def);
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check_packed(tcx, span, def);
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}
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fn check_union(tcx: TyCtxt<'_>, def_id: LocalDefId) {
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let def = tcx.adt_def(def_id);
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let span = tcx.def_span(def_id);
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def.destructor(tcx); // force the destructor to be evaluated
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check_transparent(tcx, def);
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check_union_fields(tcx, span, def_id);
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check_packed(tcx, span, def);
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}
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fn allowed_union_or_unsafe_field<'tcx>(
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tcx: TyCtxt<'tcx>,
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ty: Ty<'tcx>,
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typing_env: ty::TypingEnv<'tcx>,
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span: Span,
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) -> bool {
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// HACK (not that bad of a hack don't worry): Some codegen tests don't even define proper
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// impls for `Copy`. Let's short-circuit here for this validity check, since a lot of them
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// use unions. We should eventually fix all the tests to define that lang item or use
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// minicore stubs.
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if ty.is_trivially_pure_clone_copy() {
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return true;
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}
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// If `BikeshedGuaranteedNoDrop` is not defined in a `#[no_core]` test, fall back to `Copy`.
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// This is an underapproximation of `BikeshedGuaranteedNoDrop`,
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let def_id = tcx
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.lang_items()
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.get(LangItem::BikeshedGuaranteedNoDrop)
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.unwrap_or_else(|| tcx.require_lang_item(LangItem::Copy, Some(span)));
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let Ok(ty) = tcx.try_normalize_erasing_regions(typing_env, ty) else {
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tcx.dcx().span_delayed_bug(span, "could not normalize field type");
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return true;
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};
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let (infcx, param_env) = tcx.infer_ctxt().build_with_typing_env(typing_env);
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infcx.predicate_must_hold_modulo_regions(&Obligation::new(
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tcx,
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ObligationCause::dummy_with_span(span),
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param_env,
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ty::TraitRef::new(tcx, def_id, [ty]),
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))
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}
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/// Check that the fields of the `union` do not need dropping.
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fn check_union_fields(tcx: TyCtxt<'_>, span: Span, item_def_id: LocalDefId) -> bool {
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let def = tcx.adt_def(item_def_id);
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assert!(def.is_union());
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let typing_env = ty::TypingEnv::non_body_analysis(tcx, item_def_id);
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let args = ty::GenericArgs::identity_for_item(tcx, item_def_id);
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for field in &def.non_enum_variant().fields {
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if !allowed_union_or_unsafe_field(tcx, field.ty(tcx, args), typing_env, span) {
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let (field_span, ty_span) = match tcx.hir_get_if_local(field.did) {
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// We are currently checking the type this field came from, so it must be local.
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Some(Node::Field(field)) => (field.span, field.ty.span),
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_ => unreachable!("mir field has to correspond to hir field"),
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};
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tcx.dcx().emit_err(errors::InvalidUnionField {
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field_span,
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sugg: errors::InvalidUnionFieldSuggestion {
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lo: ty_span.shrink_to_lo(),
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hi: ty_span.shrink_to_hi(),
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},
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note: (),
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});
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return false;
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}
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}
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true
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}
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/// Check that a `static` is inhabited.
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fn check_static_inhabited(tcx: TyCtxt<'_>, def_id: LocalDefId) {
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// Make sure statics are inhabited.
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// Other parts of the compiler assume that there are no uninhabited places. In principle it
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// would be enough to check this for `extern` statics, as statics with an initializer will
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// have UB during initialization if they are uninhabited, but there also seems to be no good
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// reason to allow any statics to be uninhabited.
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let ty = tcx.type_of(def_id).instantiate_identity();
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let span = tcx.def_span(def_id);
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let layout = match tcx.layout_of(ty::TypingEnv::fully_monomorphized().as_query_input(ty)) {
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Ok(l) => l,
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// Foreign statics that overflow their allowed size should emit an error
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Err(LayoutError::SizeOverflow(_))
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if matches!(tcx.def_kind(def_id), DefKind::Static{ .. }
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if tcx.def_kind(tcx.local_parent(def_id)) == DefKind::ForeignMod) =>
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{
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tcx.dcx().emit_err(errors::TooLargeStatic { span });
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return;
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}
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// Generic statics are rejected, but we still reach this case.
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Err(e) => {
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tcx.dcx().span_delayed_bug(span, format!("{e:?}"));
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return;
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}
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};
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if layout.is_uninhabited() {
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tcx.node_span_lint(
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UNINHABITED_STATIC,
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tcx.local_def_id_to_hir_id(def_id),
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span,
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|lint| {
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lint.primary_message("static of uninhabited type");
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lint
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.note("uninhabited statics cannot be initialized, and any access would be an immediate error");
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},
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);
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}
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}
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/// Checks that an opaque type does not contain cycles and does not use `Self` or `T::Foo`
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/// projections that would result in "inheriting lifetimes".
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fn check_opaque(tcx: TyCtxt<'_>, def_id: LocalDefId) {
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let hir::OpaqueTy { origin, .. } = *tcx.hir_expect_opaque_ty(def_id);
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// HACK(jynelson): trying to infer the type of `impl trait` breaks documenting
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// `async-std` (and `pub async fn` in general).
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// Since rustdoc doesn't care about the concrete type behind `impl Trait`, just don't look at it!
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// See https://github.com/rust-lang/rust/issues/75100
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if tcx.sess.opts.actually_rustdoc {
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return;
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}
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if tcx.type_of(def_id).instantiate_identity().references_error() {
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return;
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}
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if check_opaque_for_cycles(tcx, def_id).is_err() {
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return;
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}
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let _ = check_opaque_meets_bounds(tcx, def_id, origin);
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}
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/// Checks that an opaque type does not contain cycles.
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pub(super) fn check_opaque_for_cycles<'tcx>(
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tcx: TyCtxt<'tcx>,
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def_id: LocalDefId,
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) -> Result<(), ErrorGuaranteed> {
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let args = GenericArgs::identity_for_item(tcx, def_id);
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// First, try to look at any opaque expansion cycles, considering coroutine fields
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// (even though these aren't necessarily true errors).
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if tcx.try_expand_impl_trait_type(def_id.to_def_id(), args).is_err() {
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let reported = opaque_type_cycle_error(tcx, def_id);
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return Err(reported);
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}
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Ok(())
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}
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/// Check that the concrete type behind `impl Trait` actually implements `Trait`.
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///
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/// This is mostly checked at the places that specify the opaque type, but we
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/// check those cases in the `param_env` of that function, which may have
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/// bounds not on this opaque type:
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///
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/// ```ignore (illustrative)
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/// type X<T> = impl Clone;
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/// fn f<T: Clone>(t: T) -> X<T> {
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/// t
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/// }
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/// ```
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///
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/// Without this check the above code is incorrectly accepted: we would ICE if
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/// some tried, for example, to clone an `Option<X<&mut ()>>`.
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#[instrument(level = "debug", skip(tcx))]
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fn check_opaque_meets_bounds<'tcx>(
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tcx: TyCtxt<'tcx>,
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def_id: LocalDefId,
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origin: hir::OpaqueTyOrigin<LocalDefId>,
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) -> Result<(), ErrorGuaranteed> {
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let (span, definition_def_id) =
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if let Some((span, def_id)) = best_definition_site_of_opaque(tcx, def_id, origin) {
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(span, Some(def_id))
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} else {
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(tcx.def_span(def_id), None)
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};
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let defining_use_anchor = match origin {
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hir::OpaqueTyOrigin::FnReturn { parent, .. }
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| hir::OpaqueTyOrigin::AsyncFn { parent, .. }
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| hir::OpaqueTyOrigin::TyAlias { parent, .. } => parent,
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};
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let param_env = tcx.param_env(defining_use_anchor);
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// FIXME(#132279): Once `PostBorrowckAnalysis` is supported in the old solver, this branch should be removed.
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let infcx = tcx.infer_ctxt().build(if tcx.next_trait_solver_globally() {
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TypingMode::post_borrowck_analysis(tcx, defining_use_anchor)
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} else {
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TypingMode::analysis_in_body(tcx, defining_use_anchor)
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});
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let ocx = ObligationCtxt::new_with_diagnostics(&infcx);
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let args = match origin {
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hir::OpaqueTyOrigin::FnReturn { parent, .. }
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| hir::OpaqueTyOrigin::AsyncFn { parent, .. }
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| hir::OpaqueTyOrigin::TyAlias { parent, .. } => GenericArgs::identity_for_item(
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tcx, parent,
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)
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.extend_to(tcx, def_id.to_def_id(), |param, _| {
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tcx.map_opaque_lifetime_to_parent_lifetime(param.def_id.expect_local()).into()
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}),
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};
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let opaque_ty = Ty::new_opaque(tcx, def_id.to_def_id(), args);
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// `ReErased` regions appear in the "parent_args" of closures/coroutines.
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// We're ignoring them here and replacing them with fresh region variables.
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// See tests in ui/type-alias-impl-trait/closure_{parent_args,wf_outlives}.rs.
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//
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// FIXME: Consider wrapping the hidden type in an existential `Binder` and instantiating it
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// here rather than using ReErased.
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let hidden_ty = tcx.type_of(def_id.to_def_id()).instantiate(tcx, args);
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let hidden_ty = fold_regions(tcx, hidden_ty, |re, _dbi| match re.kind() {
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ty::ReErased => infcx.next_region_var(RegionVariableOrigin::MiscVariable(span)),
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_ => re,
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});
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// HACK: We eagerly instantiate some bounds to report better errors for them...
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// This isn't necessary for correctness, since we register these bounds when
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// equating the opaque below, but we should clean this up in the new solver.
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for (predicate, pred_span) in
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tcx.explicit_item_bounds(def_id).iter_instantiated_copied(tcx, args)
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{
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let predicate = predicate.fold_with(&mut BottomUpFolder {
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tcx,
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ty_op: |ty| if ty == opaque_ty { hidden_ty } else { ty },
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lt_op: |lt| lt,
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ct_op: |ct| ct,
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});
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ocx.register_obligation(Obligation::new(
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tcx,
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ObligationCause::new(
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span,
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def_id,
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ObligationCauseCode::OpaqueTypeBound(pred_span, definition_def_id),
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),
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param_env,
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predicate,
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));
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}
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let misc_cause = ObligationCause::misc(span, def_id);
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// FIXME: We should just register the item bounds here, rather than equating.
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// FIXME(const_trait_impl): When we do that, please make sure to also register
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// the `~const` bounds.
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match ocx.eq(&misc_cause, param_env, opaque_ty, hidden_ty) {
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Ok(()) => {}
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Err(ty_err) => {
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// Some types may be left "stranded" if they can't be reached
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// from a lowered rustc_middle bound but they're mentioned in the HIR.
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// This will happen, e.g., when a nested opaque is inside of a non-
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// existent associated type, like `impl Trait<Missing = impl Trait>`.
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// See <tests/ui/impl-trait/stranded-opaque.rs>.
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let ty_err = ty_err.to_string(tcx);
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let guar = tcx.dcx().span_delayed_bug(
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span,
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format!("could not unify `{hidden_ty}` with revealed type:\n{ty_err}"),
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);
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return Err(guar);
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}
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}
|
|
|
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// Additionally require the hidden type to be well-formed with only the generics of the opaque type.
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// Defining use functions may have more bounds than the opaque type, which is ok, as long as the
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// hidden type is well formed even without those bounds.
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let predicate =
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ty::Binder::dummy(ty::PredicateKind::Clause(ty::ClauseKind::WellFormed(hidden_ty.into())));
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ocx.register_obligation(Obligation::new(tcx, misc_cause.clone(), param_env, predicate));
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|
|
|
// Check that all obligations are satisfied by the implementation's
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|
// version.
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|
let errors = ocx.select_all_or_error();
|
|
if !errors.is_empty() {
|
|
let guar = infcx.err_ctxt().report_fulfillment_errors(errors);
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|
return Err(guar);
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|
}
|
|
|
|
let wf_tys = ocx.assumed_wf_types_and_report_errors(param_env, defining_use_anchor)?;
|
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ocx.resolve_regions_and_report_errors(defining_use_anchor, param_env, wf_tys)?;
|
|
|
|
if infcx.next_trait_solver() {
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Ok(())
|
|
} else if let hir::OpaqueTyOrigin::FnReturn { .. } | hir::OpaqueTyOrigin::AsyncFn { .. } =
|
|
origin
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|
{
|
|
// HACK: this should also fall through to the hidden type check below, but the original
|
|
// implementation had a bug where equivalent lifetimes are not identical. This caused us
|
|
// to reject existing stable code that is otherwise completely fine. The real fix is to
|
|
// compare the hidden types via our type equivalence/relation infra instead of doing an
|
|
// identity check.
|
|
let _ = infcx.take_opaque_types();
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|
Ok(())
|
|
} else {
|
|
// Check that any hidden types found during wf checking match the hidden types that `type_of` sees.
|
|
for (mut key, mut ty) in infcx.take_opaque_types() {
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|
ty.ty = infcx.resolve_vars_if_possible(ty.ty);
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|
key = infcx.resolve_vars_if_possible(key);
|
|
sanity_check_found_hidden_type(tcx, key, ty)?;
|
|
}
|
|
Ok(())
|
|
}
|
|
}
|
|
|
|
fn best_definition_site_of_opaque<'tcx>(
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tcx: TyCtxt<'tcx>,
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|
opaque_def_id: LocalDefId,
|
|
origin: hir::OpaqueTyOrigin<LocalDefId>,
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|
) -> Option<(Span, LocalDefId)> {
|
|
struct TaitConstraintLocator<'tcx> {
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|
opaque_def_id: LocalDefId,
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|
tcx: TyCtxt<'tcx>,
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|
}
|
|
impl<'tcx> TaitConstraintLocator<'tcx> {
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|
fn check(&self, item_def_id: LocalDefId) -> ControlFlow<(Span, LocalDefId)> {
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|
if !self.tcx.has_typeck_results(item_def_id) {
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|
return ControlFlow::Continue(());
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|
}
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|
|
|
let opaque_types_defined_by = self.tcx.opaque_types_defined_by(item_def_id);
|
|
// Don't try to check items that cannot possibly constrain the type.
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|
if !opaque_types_defined_by.contains(&self.opaque_def_id) {
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return ControlFlow::Continue(());
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|
}
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|
|
|
if let Some(hidden_ty) =
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self.tcx.mir_borrowck(item_def_id).concrete_opaque_types.get(&self.opaque_def_id)
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|
{
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|
ControlFlow::Break((hidden_ty.span, item_def_id))
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|
} else {
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|
ControlFlow::Continue(())
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|
}
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|
}
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|
}
|
|
impl<'tcx> intravisit::Visitor<'tcx> for TaitConstraintLocator<'tcx> {
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|
type NestedFilter = nested_filter::All;
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|
type Result = ControlFlow<(Span, LocalDefId)>;
|
|
fn maybe_tcx(&mut self) -> Self::MaybeTyCtxt {
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self.tcx
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|
}
|
|
fn visit_expr(&mut self, ex: &'tcx hir::Expr<'tcx>) -> Self::Result {
|
|
if let hir::ExprKind::Closure(closure) = ex.kind {
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|
self.check(closure.def_id)?;
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|
}
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|
intravisit::walk_expr(self, ex)
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|
}
|
|
fn visit_item(&mut self, it: &'tcx hir::Item<'tcx>) -> Self::Result {
|
|
self.check(it.owner_id.def_id)?;
|
|
intravisit::walk_item(self, it)
|
|
}
|
|
fn visit_impl_item(&mut self, it: &'tcx hir::ImplItem<'tcx>) -> Self::Result {
|
|
self.check(it.owner_id.def_id)?;
|
|
intravisit::walk_impl_item(self, it)
|
|
}
|
|
fn visit_trait_item(&mut self, it: &'tcx hir::TraitItem<'tcx>) -> Self::Result {
|
|
self.check(it.owner_id.def_id)?;
|
|
intravisit::walk_trait_item(self, it)
|
|
}
|
|
fn visit_foreign_item(&mut self, it: &'tcx hir::ForeignItem<'tcx>) -> Self::Result {
|
|
intravisit::walk_foreign_item(self, it)
|
|
}
|
|
}
|
|
|
|
let mut locator = TaitConstraintLocator { tcx, opaque_def_id };
|
|
match origin {
|
|
hir::OpaqueTyOrigin::FnReturn { parent, .. }
|
|
| hir::OpaqueTyOrigin::AsyncFn { parent, .. } => locator.check(parent).break_value(),
|
|
hir::OpaqueTyOrigin::TyAlias { parent, in_assoc_ty: true } => {
|
|
let impl_def_id = tcx.local_parent(parent);
|
|
for assoc in tcx.associated_items(impl_def_id).in_definition_order() {
|
|
match assoc.kind {
|
|
ty::AssocKind::Const | ty::AssocKind::Fn => {
|
|
if let ControlFlow::Break(span) = locator.check(assoc.def_id.expect_local())
|
|
{
|
|
return Some(span);
|
|
}
|
|
}
|
|
ty::AssocKind::Type => {}
|
|
}
|
|
}
|
|
|
|
None
|
|
}
|
|
hir::OpaqueTyOrigin::TyAlias { in_assoc_ty: false, .. } => {
|
|
tcx.hir_walk_toplevel_module(&mut locator).break_value()
|
|
}
|
|
}
|
|
}
|
|
|
|
fn sanity_check_found_hidden_type<'tcx>(
|
|
tcx: TyCtxt<'tcx>,
|
|
key: ty::OpaqueTypeKey<'tcx>,
|
|
mut ty: ty::OpaqueHiddenType<'tcx>,
|
|
) -> Result<(), ErrorGuaranteed> {
|
|
if ty.ty.is_ty_var() {
|
|
// Nothing was actually constrained.
|
|
return Ok(());
|
|
}
|
|
if let ty::Alias(ty::Opaque, alias) = ty.ty.kind() {
|
|
if alias.def_id == key.def_id.to_def_id() && alias.args == key.args {
|
|
// Nothing was actually constrained, this is an opaque usage that was
|
|
// only discovered to be opaque after inference vars resolved.
|
|
return Ok(());
|
|
}
|
|
}
|
|
let strip_vars = |ty: Ty<'tcx>| {
|
|
ty.fold_with(&mut BottomUpFolder {
|
|
tcx,
|
|
ty_op: |t| t,
|
|
ct_op: |c| c,
|
|
lt_op: |l| match l.kind() {
|
|
RegionKind::ReVar(_) => tcx.lifetimes.re_erased,
|
|
_ => l,
|
|
},
|
|
})
|
|
};
|
|
// Closures frequently end up containing erased lifetimes in their final representation.
|
|
// These correspond to lifetime variables that never got resolved, so we patch this up here.
|
|
ty.ty = strip_vars(ty.ty);
|
|
// Get the hidden type.
|
|
let hidden_ty = tcx.type_of(key.def_id).instantiate(tcx, key.args);
|
|
let hidden_ty = strip_vars(hidden_ty);
|
|
|
|
// If the hidden types differ, emit a type mismatch diagnostic.
|
|
if hidden_ty == ty.ty {
|
|
Ok(())
|
|
} else {
|
|
let span = tcx.def_span(key.def_id);
|
|
let other = ty::OpaqueHiddenType { ty: hidden_ty, span };
|
|
Err(ty.build_mismatch_error(&other, tcx)?.emit())
|
|
}
|
|
}
|
|
|
|
/// Check that the opaque's precise captures list is valid (if present).
|
|
/// We check this for regular `impl Trait`s and also RPITITs, even though the latter
|
|
/// are technically GATs.
|
|
///
|
|
/// This function is responsible for:
|
|
/// 1. Checking that all type/const params are mention in the captures list.
|
|
/// 2. Checking that all lifetimes that are implicitly captured are mentioned.
|
|
/// 3. Asserting that all parameters mentioned in the captures list are invariant.
|
|
fn check_opaque_precise_captures<'tcx>(tcx: TyCtxt<'tcx>, opaque_def_id: LocalDefId) {
|
|
let hir::OpaqueTy { bounds, .. } = *tcx.hir_node_by_def_id(opaque_def_id).expect_opaque_ty();
|
|
let Some(precise_capturing_args) = bounds.iter().find_map(|bound| match *bound {
|
|
hir::GenericBound::Use(bounds, ..) => Some(bounds),
|
|
_ => None,
|
|
}) else {
|
|
// No precise capturing args; nothing to validate
|
|
return;
|
|
};
|
|
|
|
let mut expected_captures = UnordSet::default();
|
|
let mut shadowed_captures = UnordSet::default();
|
|
let mut seen_params = UnordMap::default();
|
|
let mut prev_non_lifetime_param = None;
|
|
for arg in precise_capturing_args {
|
|
let (hir_id, ident) = match *arg {
|
|
hir::PreciseCapturingArg::Param(hir::PreciseCapturingNonLifetimeArg {
|
|
hir_id,
|
|
ident,
|
|
..
|
|
}) => {
|
|
if prev_non_lifetime_param.is_none() {
|
|
prev_non_lifetime_param = Some(ident);
|
|
}
|
|
(hir_id, ident)
|
|
}
|
|
hir::PreciseCapturingArg::Lifetime(&hir::Lifetime { hir_id, ident, .. }) => {
|
|
if let Some(prev_non_lifetime_param) = prev_non_lifetime_param {
|
|
tcx.dcx().emit_err(errors::LifetimesMustBeFirst {
|
|
lifetime_span: ident.span,
|
|
name: ident.name,
|
|
other_span: prev_non_lifetime_param.span,
|
|
});
|
|
}
|
|
(hir_id, ident)
|
|
}
|
|
};
|
|
|
|
let ident = ident.normalize_to_macros_2_0();
|
|
if let Some(span) = seen_params.insert(ident, ident.span) {
|
|
tcx.dcx().emit_err(errors::DuplicatePreciseCapture {
|
|
name: ident.name,
|
|
first_span: span,
|
|
second_span: ident.span,
|
|
});
|
|
}
|
|
|
|
match tcx.named_bound_var(hir_id) {
|
|
Some(ResolvedArg::EarlyBound(def_id)) => {
|
|
expected_captures.insert(def_id.to_def_id());
|
|
|
|
// Make sure we allow capturing these lifetimes through `Self` and
|
|
// `T::Assoc` projection syntax, too. These will occur when we only
|
|
// see lifetimes are captured after hir-lowering -- this aligns with
|
|
// the cases that were stabilized with the `impl_trait_projection`
|
|
// feature -- see <https://github.com/rust-lang/rust/pull/115659>.
|
|
if let DefKind::LifetimeParam = tcx.def_kind(def_id)
|
|
&& let Some(def_id) = tcx
|
|
.map_opaque_lifetime_to_parent_lifetime(def_id)
|
|
.opt_param_def_id(tcx, tcx.parent(opaque_def_id.to_def_id()))
|
|
{
|
|
shadowed_captures.insert(def_id);
|
|
}
|
|
}
|
|
_ => {
|
|
tcx.dcx()
|
|
.span_delayed_bug(tcx.hir_span(hir_id), "parameter should have been resolved");
|
|
}
|
|
}
|
|
}
|
|
|
|
let variances = tcx.variances_of(opaque_def_id);
|
|
let mut def_id = Some(opaque_def_id.to_def_id());
|
|
while let Some(generics) = def_id {
|
|
let generics = tcx.generics_of(generics);
|
|
def_id = generics.parent;
|
|
|
|
for param in &generics.own_params {
|
|
if expected_captures.contains(¶m.def_id) {
|
|
assert_eq!(
|
|
variances[param.index as usize],
|
|
ty::Invariant,
|
|
"precise captured param should be invariant"
|
|
);
|
|
continue;
|
|
}
|
|
// If a param is shadowed by a early-bound (duplicated) lifetime, then
|
|
// it may or may not be captured as invariant, depending on if it shows
|
|
// up through `Self` or `T::Assoc` syntax.
|
|
if shadowed_captures.contains(¶m.def_id) {
|
|
continue;
|
|
}
|
|
|
|
match param.kind {
|
|
ty::GenericParamDefKind::Lifetime => {
|
|
let use_span = tcx.def_span(param.def_id);
|
|
let opaque_span = tcx.def_span(opaque_def_id);
|
|
// Check if the lifetime param was captured but isn't named in the precise captures list.
|
|
if variances[param.index as usize] == ty::Invariant {
|
|
if let DefKind::OpaqueTy = tcx.def_kind(tcx.parent(param.def_id))
|
|
&& let Some(def_id) = tcx
|
|
.map_opaque_lifetime_to_parent_lifetime(param.def_id.expect_local())
|
|
.opt_param_def_id(tcx, tcx.parent(opaque_def_id.to_def_id()))
|
|
{
|
|
tcx.dcx().emit_err(errors::LifetimeNotCaptured {
|
|
opaque_span,
|
|
use_span,
|
|
param_span: tcx.def_span(def_id),
|
|
});
|
|
} else {
|
|
if tcx.def_kind(tcx.parent(param.def_id)) == DefKind::Trait {
|
|
tcx.dcx().emit_err(errors::LifetimeImplicitlyCaptured {
|
|
opaque_span,
|
|
param_span: tcx.def_span(param.def_id),
|
|
});
|
|
} else {
|
|
// If the `use_span` is actually just the param itself, then we must
|
|
// have not duplicated the lifetime but captured the original.
|
|
// The "effective" `use_span` will be the span of the opaque itself,
|
|
// and the param span will be the def span of the param.
|
|
tcx.dcx().emit_err(errors::LifetimeNotCaptured {
|
|
opaque_span,
|
|
use_span: opaque_span,
|
|
param_span: use_span,
|
|
});
|
|
}
|
|
}
|
|
continue;
|
|
}
|
|
}
|
|
ty::GenericParamDefKind::Type { .. } => {
|
|
if matches!(tcx.def_kind(param.def_id), DefKind::Trait | DefKind::TraitAlias) {
|
|
// FIXME(precise_capturing): Structured suggestion for this would be useful
|
|
tcx.dcx().emit_err(errors::SelfTyNotCaptured {
|
|
trait_span: tcx.def_span(param.def_id),
|
|
opaque_span: tcx.def_span(opaque_def_id),
|
|
});
|
|
} else {
|
|
// FIXME(precise_capturing): Structured suggestion for this would be useful
|
|
tcx.dcx().emit_err(errors::ParamNotCaptured {
|
|
param_span: tcx.def_span(param.def_id),
|
|
opaque_span: tcx.def_span(opaque_def_id),
|
|
kind: "type",
|
|
});
|
|
}
|
|
}
|
|
ty::GenericParamDefKind::Const { .. } => {
|
|
// FIXME(precise_capturing): Structured suggestion for this would be useful
|
|
tcx.dcx().emit_err(errors::ParamNotCaptured {
|
|
param_span: tcx.def_span(param.def_id),
|
|
opaque_span: tcx.def_span(opaque_def_id),
|
|
kind: "const",
|
|
});
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
fn is_enum_of_nonnullable_ptr<'tcx>(
|
|
tcx: TyCtxt<'tcx>,
|
|
adt_def: AdtDef<'tcx>,
|
|
args: GenericArgsRef<'tcx>,
|
|
) -> bool {
|
|
if adt_def.repr().inhibit_enum_layout_opt() {
|
|
return false;
|
|
}
|
|
|
|
let [var_one, var_two] = &adt_def.variants().raw[..] else {
|
|
return false;
|
|
};
|
|
let (([], [field]) | ([field], [])) = (&var_one.fields.raw[..], &var_two.fields.raw[..]) else {
|
|
return false;
|
|
};
|
|
matches!(field.ty(tcx, args).kind(), ty::FnPtr(..) | ty::Ref(..))
|
|
}
|
|
|
|
fn check_static_linkage(tcx: TyCtxt<'_>, def_id: LocalDefId) {
|
|
if tcx.codegen_fn_attrs(def_id).import_linkage.is_some() {
|
|
if match tcx.type_of(def_id).instantiate_identity().kind() {
|
|
ty::RawPtr(_, _) => false,
|
|
ty::Adt(adt_def, args) => !is_enum_of_nonnullable_ptr(tcx, *adt_def, *args),
|
|
_ => true,
|
|
} {
|
|
tcx.dcx().emit_err(errors::LinkageType { span: tcx.def_span(def_id) });
|
|
}
|
|
}
|
|
}
|
|
|
|
pub(crate) fn check_item_type(tcx: TyCtxt<'_>, def_id: LocalDefId) {
|
|
match tcx.def_kind(def_id) {
|
|
DefKind::Static { .. } => {
|
|
check_static_inhabited(tcx, def_id);
|
|
check_static_linkage(tcx, def_id);
|
|
}
|
|
DefKind::Const => {}
|
|
DefKind::Enum => {
|
|
check_enum(tcx, def_id);
|
|
}
|
|
DefKind::Fn => {
|
|
if let Some(i) = tcx.intrinsic(def_id) {
|
|
intrinsic::check_intrinsic_type(
|
|
tcx,
|
|
def_id,
|
|
tcx.def_ident_span(def_id).unwrap(),
|
|
i.name,
|
|
ExternAbi::Rust,
|
|
)
|
|
}
|
|
}
|
|
DefKind::Impl { of_trait } => {
|
|
if of_trait && let Some(impl_trait_header) = tcx.impl_trait_header(def_id) {
|
|
if tcx
|
|
.ensure_ok()
|
|
.coherent_trait(impl_trait_header.trait_ref.instantiate_identity().def_id)
|
|
.is_ok()
|
|
{
|
|
check_impl_items_against_trait(tcx, def_id, impl_trait_header);
|
|
check_on_unimplemented(tcx, def_id);
|
|
}
|
|
}
|
|
}
|
|
DefKind::Trait => {
|
|
let assoc_items = tcx.associated_items(def_id);
|
|
check_on_unimplemented(tcx, def_id);
|
|
|
|
for &assoc_item in assoc_items.in_definition_order() {
|
|
match assoc_item.kind {
|
|
ty::AssocKind::Fn => {
|
|
let abi = tcx.fn_sig(assoc_item.def_id).skip_binder().abi();
|
|
forbid_intrinsic_abi(tcx, assoc_item.ident(tcx).span, abi);
|
|
}
|
|
ty::AssocKind::Type if assoc_item.defaultness(tcx).has_value() => {
|
|
let trait_args = GenericArgs::identity_for_item(tcx, def_id);
|
|
let _: Result<_, rustc_errors::ErrorGuaranteed> = check_type_bounds(
|
|
tcx,
|
|
assoc_item,
|
|
assoc_item,
|
|
ty::TraitRef::new_from_args(tcx, def_id.to_def_id(), trait_args),
|
|
);
|
|
}
|
|
_ => {}
|
|
}
|
|
}
|
|
}
|
|
DefKind::Struct => {
|
|
check_struct(tcx, def_id);
|
|
}
|
|
DefKind::Union => {
|
|
check_union(tcx, def_id);
|
|
}
|
|
DefKind::OpaqueTy => {
|
|
check_opaque_precise_captures(tcx, def_id);
|
|
|
|
let origin = tcx.local_opaque_ty_origin(def_id);
|
|
if let hir::OpaqueTyOrigin::FnReturn { parent: fn_def_id, .. }
|
|
| hir::OpaqueTyOrigin::AsyncFn { parent: fn_def_id, .. } = origin
|
|
&& let hir::Node::TraitItem(trait_item) = tcx.hir_node_by_def_id(fn_def_id)
|
|
&& let (_, hir::TraitFn::Required(..)) = trait_item.expect_fn()
|
|
{
|
|
// Skip opaques from RPIT in traits with no default body.
|
|
} else {
|
|
check_opaque(tcx, def_id);
|
|
}
|
|
}
|
|
DefKind::TyAlias => {
|
|
check_type_alias_type_params_are_used(tcx, def_id);
|
|
}
|
|
DefKind::ForeignMod => {
|
|
let it = tcx.hir_expect_item(def_id);
|
|
let hir::ItemKind::ForeignMod { abi, items } = it.kind else {
|
|
return;
|
|
};
|
|
check_abi(tcx, it.span, abi);
|
|
|
|
match abi {
|
|
ExternAbi::RustIntrinsic => {
|
|
for item in items {
|
|
intrinsic::check_intrinsic_type(
|
|
tcx,
|
|
item.id.owner_id.def_id,
|
|
item.span,
|
|
item.ident.name,
|
|
abi,
|
|
);
|
|
}
|
|
}
|
|
|
|
_ => {
|
|
for item in items {
|
|
let def_id = item.id.owner_id.def_id;
|
|
let generics = tcx.generics_of(def_id);
|
|
let own_counts = generics.own_counts();
|
|
if generics.own_params.len() - own_counts.lifetimes != 0 {
|
|
let (kinds, kinds_pl, egs) = match (own_counts.types, own_counts.consts)
|
|
{
|
|
(_, 0) => ("type", "types", Some("u32")),
|
|
// We don't specify an example value, because we can't generate
|
|
// a valid value for any type.
|
|
(0, _) => ("const", "consts", None),
|
|
_ => ("type or const", "types or consts", None),
|
|
};
|
|
struct_span_code_err!(
|
|
tcx.dcx(),
|
|
item.span,
|
|
E0044,
|
|
"foreign items may not have {kinds} parameters",
|
|
)
|
|
.with_span_label(item.span, format!("can't have {kinds} parameters"))
|
|
.with_help(
|
|
// FIXME: once we start storing spans for type arguments, turn this
|
|
// into a suggestion.
|
|
format!(
|
|
"replace the {} parameters with concrete {}{}",
|
|
kinds,
|
|
kinds_pl,
|
|
egs.map(|egs| format!(" like `{egs}`")).unwrap_or_default(),
|
|
),
|
|
)
|
|
.emit();
|
|
}
|
|
|
|
let item = tcx.hir_foreign_item(item.id);
|
|
match &item.kind {
|
|
hir::ForeignItemKind::Fn(sig, _, _) => {
|
|
require_c_abi_if_c_variadic(tcx, sig.decl, abi, item.span);
|
|
}
|
|
hir::ForeignItemKind::Static(..) => {
|
|
check_static_inhabited(tcx, def_id);
|
|
check_static_linkage(tcx, def_id);
|
|
}
|
|
_ => {}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
_ => {}
|
|
}
|
|
}
|
|
|
|
pub(super) fn check_on_unimplemented(tcx: TyCtxt<'_>, def_id: LocalDefId) {
|
|
// an error would be reported if this fails.
|
|
let _ = OnUnimplementedDirective::of_item(tcx, def_id.to_def_id());
|
|
}
|
|
|
|
pub(super) fn check_specialization_validity<'tcx>(
|
|
tcx: TyCtxt<'tcx>,
|
|
trait_def: &ty::TraitDef,
|
|
trait_item: ty::AssocItem,
|
|
impl_id: DefId,
|
|
impl_item: DefId,
|
|
) {
|
|
let Ok(ancestors) = trait_def.ancestors(tcx, impl_id) else { return };
|
|
let mut ancestor_impls = ancestors.skip(1).filter_map(|parent| {
|
|
if parent.is_from_trait() {
|
|
None
|
|
} else {
|
|
Some((parent, parent.item(tcx, trait_item.def_id)))
|
|
}
|
|
});
|
|
|
|
let opt_result = ancestor_impls.find_map(|(parent_impl, parent_item)| {
|
|
match parent_item {
|
|
// Parent impl exists, and contains the parent item we're trying to specialize, but
|
|
// doesn't mark it `default`.
|
|
Some(parent_item) if traits::impl_item_is_final(tcx, &parent_item) => {
|
|
Some(Err(parent_impl.def_id()))
|
|
}
|
|
|
|
// Parent impl contains item and makes it specializable.
|
|
Some(_) => Some(Ok(())),
|
|
|
|
// Parent impl doesn't mention the item. This means it's inherited from the
|
|
// grandparent. In that case, if parent is a `default impl`, inherited items use the
|
|
// "defaultness" from the grandparent, else they are final.
|
|
None => {
|
|
if tcx.defaultness(parent_impl.def_id()).is_default() {
|
|
None
|
|
} else {
|
|
Some(Err(parent_impl.def_id()))
|
|
}
|
|
}
|
|
}
|
|
});
|
|
|
|
// If `opt_result` is `None`, we have only encountered `default impl`s that don't contain the
|
|
// item. This is allowed, the item isn't actually getting specialized here.
|
|
let result = opt_result.unwrap_or(Ok(()));
|
|
|
|
if let Err(parent_impl) = result {
|
|
if !tcx.is_impl_trait_in_trait(impl_item) {
|
|
report_forbidden_specialization(tcx, impl_item, parent_impl);
|
|
} else {
|
|
tcx.dcx().delayed_bug(format!("parent item: {parent_impl:?} not marked as default"));
|
|
}
|
|
}
|
|
}
|
|
|
|
fn check_impl_items_against_trait<'tcx>(
|
|
tcx: TyCtxt<'tcx>,
|
|
impl_id: LocalDefId,
|
|
impl_trait_header: ty::ImplTraitHeader<'tcx>,
|
|
) {
|
|
let trait_ref = impl_trait_header.trait_ref.instantiate_identity();
|
|
// If the trait reference itself is erroneous (so the compilation is going
|
|
// to fail), skip checking the items here -- the `impl_item` table in `tcx`
|
|
// isn't populated for such impls.
|
|
if trait_ref.references_error() {
|
|
return;
|
|
}
|
|
|
|
let impl_item_refs = tcx.associated_item_def_ids(impl_id);
|
|
|
|
// Negative impls are not expected to have any items
|
|
match impl_trait_header.polarity {
|
|
ty::ImplPolarity::Reservation | ty::ImplPolarity::Positive => {}
|
|
ty::ImplPolarity::Negative => {
|
|
if let [first_item_ref, ..] = impl_item_refs {
|
|
let first_item_span = tcx.def_span(first_item_ref);
|
|
struct_span_code_err!(
|
|
tcx.dcx(),
|
|
first_item_span,
|
|
E0749,
|
|
"negative impls cannot have any items"
|
|
)
|
|
.emit();
|
|
}
|
|
return;
|
|
}
|
|
}
|
|
|
|
let trait_def = tcx.trait_def(trait_ref.def_id);
|
|
|
|
let infcx = tcx.infer_ctxt().ignoring_regions().build(TypingMode::non_body_analysis());
|
|
|
|
let ocx = ObligationCtxt::new_with_diagnostics(&infcx);
|
|
let cause = ObligationCause::misc(tcx.def_span(impl_id), impl_id);
|
|
let param_env = tcx.param_env(impl_id);
|
|
|
|
let self_is_guaranteed_unsized = match tcx
|
|
.struct_tail_raw(
|
|
trait_ref.self_ty(),
|
|
|ty| {
|
|
ocx.structurally_normalize_ty(&cause, param_env, ty).unwrap_or_else(|_| {
|
|
Ty::new_error_with_message(
|
|
tcx,
|
|
tcx.def_span(impl_id),
|
|
"struct tail should be computable",
|
|
)
|
|
})
|
|
},
|
|
|| (),
|
|
)
|
|
.kind()
|
|
{
|
|
ty::Dynamic(_, _, ty::DynKind::Dyn) | ty::Slice(_) | ty::Str => true,
|
|
_ => false,
|
|
};
|
|
|
|
for &impl_item in impl_item_refs {
|
|
let ty_impl_item = tcx.associated_item(impl_item);
|
|
let ty_trait_item = if let Some(trait_item_id) = ty_impl_item.trait_item_def_id {
|
|
tcx.associated_item(trait_item_id)
|
|
} else {
|
|
// Checked in `associated_item`.
|
|
tcx.dcx().span_delayed_bug(tcx.def_span(impl_item), "missing associated item in trait");
|
|
continue;
|
|
};
|
|
|
|
let res = tcx.ensure_ok().compare_impl_item(impl_item.expect_local());
|
|
|
|
if res.is_ok() {
|
|
match ty_impl_item.kind {
|
|
ty::AssocKind::Fn => {
|
|
compare_impl_item::refine::check_refining_return_position_impl_trait_in_trait(
|
|
tcx,
|
|
ty_impl_item,
|
|
ty_trait_item,
|
|
tcx.impl_trait_ref(ty_impl_item.container_id(tcx))
|
|
.unwrap()
|
|
.instantiate_identity(),
|
|
);
|
|
}
|
|
ty::AssocKind::Const => {}
|
|
ty::AssocKind::Type => {}
|
|
}
|
|
}
|
|
|
|
if self_is_guaranteed_unsized && tcx.generics_require_sized_self(ty_trait_item.def_id) {
|
|
tcx.emit_node_span_lint(
|
|
rustc_lint_defs::builtin::DEAD_CODE,
|
|
tcx.local_def_id_to_hir_id(ty_impl_item.def_id.expect_local()),
|
|
tcx.def_span(ty_impl_item.def_id),
|
|
errors::UselessImplItem,
|
|
)
|
|
}
|
|
|
|
check_specialization_validity(
|
|
tcx,
|
|
trait_def,
|
|
ty_trait_item,
|
|
impl_id.to_def_id(),
|
|
impl_item,
|
|
);
|
|
}
|
|
|
|
if let Ok(ancestors) = trait_def.ancestors(tcx, impl_id.to_def_id()) {
|
|
// Check for missing items from trait
|
|
let mut missing_items = Vec::new();
|
|
|
|
let mut must_implement_one_of: Option<&[Ident]> =
|
|
trait_def.must_implement_one_of.as_deref();
|
|
|
|
for &trait_item_id in tcx.associated_item_def_ids(trait_ref.def_id) {
|
|
let leaf_def = ancestors.leaf_def(tcx, trait_item_id);
|
|
|
|
let is_implemented = leaf_def
|
|
.as_ref()
|
|
.is_some_and(|node_item| node_item.item.defaultness(tcx).has_value());
|
|
|
|
if !is_implemented
|
|
&& tcx.defaultness(impl_id).is_final()
|
|
// unsized types don't need to implement methods that have `Self: Sized` bounds.
|
|
&& !(self_is_guaranteed_unsized && tcx.generics_require_sized_self(trait_item_id))
|
|
{
|
|
missing_items.push(tcx.associated_item(trait_item_id));
|
|
}
|
|
|
|
// true if this item is specifically implemented in this impl
|
|
let is_implemented_here =
|
|
leaf_def.as_ref().is_some_and(|node_item| !node_item.defining_node.is_from_trait());
|
|
|
|
if !is_implemented_here {
|
|
let full_impl_span = tcx.hir_span_with_body(tcx.local_def_id_to_hir_id(impl_id));
|
|
match tcx.eval_default_body_stability(trait_item_id, full_impl_span) {
|
|
EvalResult::Deny { feature, reason, issue, .. } => default_body_is_unstable(
|
|
tcx,
|
|
full_impl_span,
|
|
trait_item_id,
|
|
feature,
|
|
reason,
|
|
issue,
|
|
),
|
|
|
|
// Unmarked default bodies are considered stable (at least for now).
|
|
EvalResult::Allow | EvalResult::Unmarked => {}
|
|
}
|
|
}
|
|
|
|
if let Some(required_items) = &must_implement_one_of {
|
|
if is_implemented_here {
|
|
let trait_item = tcx.associated_item(trait_item_id);
|
|
if required_items.contains(&trait_item.ident(tcx)) {
|
|
must_implement_one_of = None;
|
|
}
|
|
}
|
|
}
|
|
|
|
if let Some(leaf_def) = &leaf_def
|
|
&& !leaf_def.is_final()
|
|
&& let def_id = leaf_def.item.def_id
|
|
&& tcx.impl_method_has_trait_impl_trait_tys(def_id)
|
|
{
|
|
let def_kind = tcx.def_kind(def_id);
|
|
let descr = tcx.def_kind_descr(def_kind, def_id);
|
|
let (msg, feature) = if tcx.asyncness(def_id).is_async() {
|
|
(
|
|
format!("async {descr} in trait cannot be specialized"),
|
|
"async functions in traits",
|
|
)
|
|
} else {
|
|
(
|
|
format!(
|
|
"{descr} with return-position `impl Trait` in trait cannot be specialized"
|
|
),
|
|
"return position `impl Trait` in traits",
|
|
)
|
|
};
|
|
tcx.dcx()
|
|
.struct_span_err(tcx.def_span(def_id), msg)
|
|
.with_note(format!(
|
|
"specialization behaves in inconsistent and surprising ways with \
|
|
{feature}, and for now is disallowed"
|
|
))
|
|
.emit();
|
|
}
|
|
}
|
|
|
|
if !missing_items.is_empty() {
|
|
let full_impl_span = tcx.hir_span_with_body(tcx.local_def_id_to_hir_id(impl_id));
|
|
missing_items_err(tcx, impl_id, &missing_items, full_impl_span);
|
|
}
|
|
|
|
if let Some(missing_items) = must_implement_one_of {
|
|
let attr_span = tcx
|
|
.get_attr(trait_ref.def_id, sym::rustc_must_implement_one_of)
|
|
.map(|attr| attr.span());
|
|
|
|
missing_items_must_implement_one_of_err(
|
|
tcx,
|
|
tcx.def_span(impl_id),
|
|
missing_items,
|
|
attr_span,
|
|
);
|
|
}
|
|
}
|
|
}
|
|
|
|
fn check_simd(tcx: TyCtxt<'_>, sp: Span, def_id: LocalDefId) {
|
|
let t = tcx.type_of(def_id).instantiate_identity();
|
|
if let ty::Adt(def, args) = t.kind()
|
|
&& def.is_struct()
|
|
{
|
|
let fields = &def.non_enum_variant().fields;
|
|
if fields.is_empty() {
|
|
struct_span_code_err!(tcx.dcx(), sp, E0075, "SIMD vector cannot be empty").emit();
|
|
return;
|
|
}
|
|
|
|
let array_field = &fields[FieldIdx::ZERO];
|
|
let array_ty = array_field.ty(tcx, args);
|
|
let ty::Array(element_ty, len_const) = array_ty.kind() else {
|
|
struct_span_code_err!(
|
|
tcx.dcx(),
|
|
sp,
|
|
E0076,
|
|
"SIMD vector's only field must be an array"
|
|
)
|
|
.with_span_label(tcx.def_span(array_field.did), "not an array")
|
|
.emit();
|
|
return;
|
|
};
|
|
|
|
if let Some(second_field) = fields.get(FieldIdx::from_u32(1)) {
|
|
struct_span_code_err!(tcx.dcx(), sp, E0075, "SIMD vector cannot have multiple fields")
|
|
.with_span_label(tcx.def_span(second_field.did), "excess field")
|
|
.emit();
|
|
return;
|
|
}
|
|
|
|
// FIXME(repr_simd): This check is nice, but perhaps unnecessary due to the fact
|
|
// we do not expect users to implement their own `repr(simd)` types. If they could,
|
|
// this check is easily side-steppable by hiding the const behind normalization.
|
|
// The consequence is that the error is, in general, only observable post-mono.
|
|
if let Some(len) = len_const.try_to_target_usize(tcx) {
|
|
if len == 0 {
|
|
struct_span_code_err!(tcx.dcx(), sp, E0075, "SIMD vector cannot be empty").emit();
|
|
return;
|
|
} else if len > MAX_SIMD_LANES {
|
|
struct_span_code_err!(
|
|
tcx.dcx(),
|
|
sp,
|
|
E0075,
|
|
"SIMD vector cannot have more than {MAX_SIMD_LANES} elements",
|
|
)
|
|
.emit();
|
|
return;
|
|
}
|
|
}
|
|
|
|
// Check that we use types valid for use in the lanes of a SIMD "vector register"
|
|
// These are scalar types which directly match a "machine" type
|
|
// Yes: Integers, floats, "thin" pointers
|
|
// No: char, "wide" pointers, compound types
|
|
match element_ty.kind() {
|
|
ty::Param(_) => (), // pass struct<T>([T; 4]) through, let monomorphization catch errors
|
|
ty::Int(_) | ty::Uint(_) | ty::Float(_) | ty::RawPtr(_, _) => (), // struct([u8; 4]) is ok
|
|
_ => {
|
|
struct_span_code_err!(
|
|
tcx.dcx(),
|
|
sp,
|
|
E0077,
|
|
"SIMD vector element type should be a \
|
|
primitive scalar (integer/float/pointer) type"
|
|
)
|
|
.emit();
|
|
return;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
pub(super) fn check_packed(tcx: TyCtxt<'_>, sp: Span, def: ty::AdtDef<'_>) {
|
|
let repr = def.repr();
|
|
if repr.packed() {
|
|
if let Some(reprs) =
|
|
attr::find_attr!(tcx.get_all_attrs(def.did()), AttributeKind::Repr(r) => r)
|
|
{
|
|
for (r, _) in reprs {
|
|
if let ReprPacked(pack) = r
|
|
&& let Some(repr_pack) = repr.pack
|
|
&& pack != &repr_pack
|
|
{
|
|
struct_span_code_err!(
|
|
tcx.dcx(),
|
|
sp,
|
|
E0634,
|
|
"type has conflicting packed representation hints"
|
|
)
|
|
.emit();
|
|
}
|
|
}
|
|
}
|
|
if repr.align.is_some() {
|
|
struct_span_code_err!(
|
|
tcx.dcx(),
|
|
sp,
|
|
E0587,
|
|
"type has conflicting packed and align representation hints"
|
|
)
|
|
.emit();
|
|
} else if let Some(def_spans) = check_packed_inner(tcx, def.did(), &mut vec![]) {
|
|
let mut err = struct_span_code_err!(
|
|
tcx.dcx(),
|
|
sp,
|
|
E0588,
|
|
"packed type cannot transitively contain a `#[repr(align)]` type"
|
|
);
|
|
|
|
err.span_note(
|
|
tcx.def_span(def_spans[0].0),
|
|
format!("`{}` has a `#[repr(align)]` attribute", tcx.item_name(def_spans[0].0)),
|
|
);
|
|
|
|
if def_spans.len() > 2 {
|
|
let mut first = true;
|
|
for (adt_def, span) in def_spans.iter().skip(1).rev() {
|
|
let ident = tcx.item_name(*adt_def);
|
|
err.span_note(
|
|
*span,
|
|
if first {
|
|
format!(
|
|
"`{}` contains a field of type `{}`",
|
|
tcx.type_of(def.did()).instantiate_identity(),
|
|
ident
|
|
)
|
|
} else {
|
|
format!("...which contains a field of type `{ident}`")
|
|
},
|
|
);
|
|
first = false;
|
|
}
|
|
}
|
|
|
|
err.emit();
|
|
}
|
|
}
|
|
}
|
|
|
|
pub(super) fn check_packed_inner(
|
|
tcx: TyCtxt<'_>,
|
|
def_id: DefId,
|
|
stack: &mut Vec<DefId>,
|
|
) -> Option<Vec<(DefId, Span)>> {
|
|
if let ty::Adt(def, args) = tcx.type_of(def_id).instantiate_identity().kind() {
|
|
if def.is_struct() || def.is_union() {
|
|
if def.repr().align.is_some() {
|
|
return Some(vec![(def.did(), DUMMY_SP)]);
|
|
}
|
|
|
|
stack.push(def_id);
|
|
for field in &def.non_enum_variant().fields {
|
|
if let ty::Adt(def, _) = field.ty(tcx, args).kind()
|
|
&& !stack.contains(&def.did())
|
|
&& let Some(mut defs) = check_packed_inner(tcx, def.did(), stack)
|
|
{
|
|
defs.push((def.did(), field.ident(tcx).span));
|
|
return Some(defs);
|
|
}
|
|
}
|
|
stack.pop();
|
|
}
|
|
}
|
|
|
|
None
|
|
}
|
|
|
|
pub(super) fn check_transparent<'tcx>(tcx: TyCtxt<'tcx>, adt: ty::AdtDef<'tcx>) {
|
|
if !adt.repr().transparent() {
|
|
return;
|
|
}
|
|
|
|
if adt.is_union() && !tcx.features().transparent_unions() {
|
|
feature_err(
|
|
&tcx.sess,
|
|
sym::transparent_unions,
|
|
tcx.def_span(adt.did()),
|
|
"transparent unions are unstable",
|
|
)
|
|
.emit();
|
|
}
|
|
|
|
if adt.variants().len() != 1 {
|
|
bad_variant_count(tcx, adt, tcx.def_span(adt.did()), adt.did());
|
|
// Don't bother checking the fields.
|
|
return;
|
|
}
|
|
|
|
// For each field, figure out if it's known to have "trivial" layout (i.e., is a 1-ZST), with
|
|
// "known" respecting #[non_exhaustive] attributes.
|
|
let field_infos = adt.all_fields().map(|field| {
|
|
let ty = field.ty(tcx, GenericArgs::identity_for_item(tcx, field.did));
|
|
let typing_env = ty::TypingEnv::non_body_analysis(tcx, field.did);
|
|
let layout = tcx.layout_of(typing_env.as_query_input(ty));
|
|
// We are currently checking the type this field came from, so it must be local
|
|
let span = tcx.hir_span_if_local(field.did).unwrap();
|
|
let trivial = layout.is_ok_and(|layout| layout.is_1zst());
|
|
if !trivial {
|
|
return (span, trivial, None);
|
|
}
|
|
// Even some 1-ZST fields are not allowed though, if they have `non_exhaustive`.
|
|
|
|
fn check_non_exhaustive<'tcx>(
|
|
tcx: TyCtxt<'tcx>,
|
|
t: Ty<'tcx>,
|
|
) -> ControlFlow<(&'static str, DefId, GenericArgsRef<'tcx>, bool)> {
|
|
match t.kind() {
|
|
ty::Tuple(list) => list.iter().try_for_each(|t| check_non_exhaustive(tcx, t)),
|
|
ty::Array(ty, _) => check_non_exhaustive(tcx, *ty),
|
|
ty::Adt(def, args) => {
|
|
if !def.did().is_local() && !tcx.has_attr(def.did(), sym::rustc_pub_transparent)
|
|
{
|
|
let non_exhaustive = def.is_variant_list_non_exhaustive()
|
|
|| def
|
|
.variants()
|
|
.iter()
|
|
.any(ty::VariantDef::is_field_list_non_exhaustive);
|
|
let has_priv = def.all_fields().any(|f| !f.vis.is_public());
|
|
if non_exhaustive || has_priv {
|
|
return ControlFlow::Break((
|
|
def.descr(),
|
|
def.did(),
|
|
args,
|
|
non_exhaustive,
|
|
));
|
|
}
|
|
}
|
|
def.all_fields()
|
|
.map(|field| field.ty(tcx, args))
|
|
.try_for_each(|t| check_non_exhaustive(tcx, t))
|
|
}
|
|
_ => ControlFlow::Continue(()),
|
|
}
|
|
}
|
|
|
|
(span, trivial, check_non_exhaustive(tcx, ty).break_value())
|
|
});
|
|
|
|
let non_trivial_fields = field_infos
|
|
.clone()
|
|
.filter_map(|(span, trivial, _non_exhaustive)| if !trivial { Some(span) } else { None });
|
|
let non_trivial_count = non_trivial_fields.clone().count();
|
|
if non_trivial_count >= 2 {
|
|
bad_non_zero_sized_fields(
|
|
tcx,
|
|
adt,
|
|
non_trivial_count,
|
|
non_trivial_fields,
|
|
tcx.def_span(adt.did()),
|
|
);
|
|
return;
|
|
}
|
|
let mut prev_non_exhaustive_1zst = false;
|
|
for (span, _trivial, non_exhaustive_1zst) in field_infos {
|
|
if let Some((descr, def_id, args, non_exhaustive)) = non_exhaustive_1zst {
|
|
// If there are any non-trivial fields, then there can be no non-exhaustive 1-zsts.
|
|
// Otherwise, it's only an issue if there's >1 non-exhaustive 1-zst.
|
|
if non_trivial_count > 0 || prev_non_exhaustive_1zst {
|
|
tcx.node_span_lint(
|
|
REPR_TRANSPARENT_EXTERNAL_PRIVATE_FIELDS,
|
|
tcx.local_def_id_to_hir_id(adt.did().expect_local()),
|
|
span,
|
|
|lint| {
|
|
lint.primary_message(
|
|
"zero-sized fields in `repr(transparent)` cannot \
|
|
contain external non-exhaustive types",
|
|
);
|
|
let note = if non_exhaustive {
|
|
"is marked with `#[non_exhaustive]`"
|
|
} else {
|
|
"contains private fields"
|
|
};
|
|
let field_ty = tcx.def_path_str_with_args(def_id, args);
|
|
lint.note(format!(
|
|
"this {descr} contains `{field_ty}`, which {note}, \
|
|
and makes it not a breaking change to become \
|
|
non-zero-sized in the future."
|
|
));
|
|
},
|
|
)
|
|
} else {
|
|
prev_non_exhaustive_1zst = true;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
#[allow(trivial_numeric_casts)]
|
|
fn check_enum(tcx: TyCtxt<'_>, def_id: LocalDefId) {
|
|
let def = tcx.adt_def(def_id);
|
|
def.destructor(tcx); // force the destructor to be evaluated
|
|
|
|
if def.variants().is_empty() {
|
|
attr::find_attr!(
|
|
tcx.get_all_attrs(def_id),
|
|
AttributeKind::Repr(rs) => {
|
|
struct_span_code_err!(
|
|
tcx.dcx(),
|
|
rs.first().unwrap().1,
|
|
E0084,
|
|
"unsupported representation for zero-variant enum"
|
|
)
|
|
.with_span_label(tcx.def_span(def_id), "zero-variant enum")
|
|
.emit();
|
|
}
|
|
);
|
|
}
|
|
|
|
let repr_type_ty = def.repr().discr_type().to_ty(tcx);
|
|
if repr_type_ty == tcx.types.i128 || repr_type_ty == tcx.types.u128 {
|
|
if !tcx.features().repr128() {
|
|
feature_err(
|
|
&tcx.sess,
|
|
sym::repr128,
|
|
tcx.def_span(def_id),
|
|
"repr with 128-bit type is unstable",
|
|
)
|
|
.emit();
|
|
}
|
|
}
|
|
|
|
for v in def.variants() {
|
|
if let ty::VariantDiscr::Explicit(discr_def_id) = v.discr {
|
|
tcx.ensure_ok().typeck(discr_def_id.expect_local());
|
|
}
|
|
}
|
|
|
|
if def.repr().int.is_none() {
|
|
let is_unit = |var: &ty::VariantDef| matches!(var.ctor_kind(), Some(CtorKind::Const));
|
|
let has_disr = |var: &ty::VariantDef| matches!(var.discr, ty::VariantDiscr::Explicit(_));
|
|
|
|
let has_non_units = def.variants().iter().any(|var| !is_unit(var));
|
|
let disr_units = def.variants().iter().any(|var| is_unit(var) && has_disr(var));
|
|
let disr_non_unit = def.variants().iter().any(|var| !is_unit(var) && has_disr(var));
|
|
|
|
if disr_non_unit || (disr_units && has_non_units) {
|
|
struct_span_code_err!(
|
|
tcx.dcx(),
|
|
tcx.def_span(def_id),
|
|
E0732,
|
|
"`#[repr(inttype)]` must be specified"
|
|
)
|
|
.emit();
|
|
}
|
|
}
|
|
|
|
detect_discriminant_duplicate(tcx, def);
|
|
check_transparent(tcx, def);
|
|
}
|
|
|
|
/// Part of enum check. Given the discriminants of an enum, errors if two or more discriminants are equal
|
|
fn detect_discriminant_duplicate<'tcx>(tcx: TyCtxt<'tcx>, adt: ty::AdtDef<'tcx>) {
|
|
// Helper closure to reduce duplicate code. This gets called everytime we detect a duplicate.
|
|
// Here `idx` refers to the order of which the discriminant appears, and its index in `vs`
|
|
let report = |dis: Discr<'tcx>, idx, err: &mut Diag<'_>| {
|
|
let var = adt.variant(idx); // HIR for the duplicate discriminant
|
|
let (span, display_discr) = match var.discr {
|
|
ty::VariantDiscr::Explicit(discr_def_id) => {
|
|
// In the case the discriminant is both a duplicate and overflowed, let the user know
|
|
if let hir::Node::AnonConst(expr) =
|
|
tcx.hir_node_by_def_id(discr_def_id.expect_local())
|
|
&& let hir::ExprKind::Lit(lit) = &tcx.hir_body(expr.body).value.kind
|
|
&& let rustc_ast::LitKind::Int(lit_value, _int_kind) = &lit.node
|
|
&& *lit_value != dis.val
|
|
{
|
|
(tcx.def_span(discr_def_id), format!("`{dis}` (overflowed from `{lit_value}`)"))
|
|
} else {
|
|
// Otherwise, format the value as-is
|
|
(tcx.def_span(discr_def_id), format!("`{dis}`"))
|
|
}
|
|
}
|
|
// This should not happen.
|
|
ty::VariantDiscr::Relative(0) => (tcx.def_span(var.def_id), format!("`{dis}`")),
|
|
ty::VariantDiscr::Relative(distance_to_explicit) => {
|
|
// At this point we know this discriminant is a duplicate, and was not explicitly
|
|
// assigned by the user. Here we iterate backwards to fetch the HIR for the last
|
|
// explicitly assigned discriminant, and letting the user know that this was the
|
|
// increment startpoint, and how many steps from there leading to the duplicate
|
|
if let Some(explicit_idx) =
|
|
idx.as_u32().checked_sub(distance_to_explicit).map(VariantIdx::from_u32)
|
|
{
|
|
let explicit_variant = adt.variant(explicit_idx);
|
|
let ve_ident = var.name;
|
|
let ex_ident = explicit_variant.name;
|
|
let sp = if distance_to_explicit > 1 { "variants" } else { "variant" };
|
|
|
|
err.span_label(
|
|
tcx.def_span(explicit_variant.def_id),
|
|
format!(
|
|
"discriminant for `{ve_ident}` incremented from this startpoint \
|
|
(`{ex_ident}` + {distance_to_explicit} {sp} later \
|
|
=> `{ve_ident}` = {dis})"
|
|
),
|
|
);
|
|
}
|
|
|
|
(tcx.def_span(var.def_id), format!("`{dis}`"))
|
|
}
|
|
};
|
|
|
|
err.span_label(span, format!("{display_discr} assigned here"));
|
|
};
|
|
|
|
let mut discrs = adt.discriminants(tcx).collect::<Vec<_>>();
|
|
|
|
// Here we loop through the discriminants, comparing each discriminant to another.
|
|
// When a duplicate is detected, we instantiate an error and point to both
|
|
// initial and duplicate value. The duplicate discriminant is then discarded by swapping
|
|
// it with the last element and decrementing the `vec.len` (which is why we have to evaluate
|
|
// `discrs.len()` anew every iteration, and why this could be tricky to do in a functional
|
|
// style as we are mutating `discrs` on the fly).
|
|
let mut i = 0;
|
|
while i < discrs.len() {
|
|
let var_i_idx = discrs[i].0;
|
|
let mut error: Option<Diag<'_, _>> = None;
|
|
|
|
let mut o = i + 1;
|
|
while o < discrs.len() {
|
|
let var_o_idx = discrs[o].0;
|
|
|
|
if discrs[i].1.val == discrs[o].1.val {
|
|
let err = error.get_or_insert_with(|| {
|
|
let mut ret = struct_span_code_err!(
|
|
tcx.dcx(),
|
|
tcx.def_span(adt.did()),
|
|
E0081,
|
|
"discriminant value `{}` assigned more than once",
|
|
discrs[i].1,
|
|
);
|
|
|
|
report(discrs[i].1, var_i_idx, &mut ret);
|
|
|
|
ret
|
|
});
|
|
|
|
report(discrs[o].1, var_o_idx, err);
|
|
|
|
// Safe to unwrap here, as we wouldn't reach this point if `discrs` was empty
|
|
discrs[o] = *discrs.last().unwrap();
|
|
discrs.pop();
|
|
} else {
|
|
o += 1;
|
|
}
|
|
}
|
|
|
|
if let Some(e) = error {
|
|
e.emit();
|
|
}
|
|
|
|
i += 1;
|
|
}
|
|
}
|
|
|
|
fn check_type_alias_type_params_are_used<'tcx>(tcx: TyCtxt<'tcx>, def_id: LocalDefId) {
|
|
if tcx.type_alias_is_lazy(def_id) {
|
|
// Since we compute the variances for lazy type aliases and already reject bivariant
|
|
// parameters as unused, we can and should skip this check for lazy type aliases.
|
|
return;
|
|
}
|
|
|
|
let generics = tcx.generics_of(def_id);
|
|
if generics.own_counts().types == 0 {
|
|
return;
|
|
}
|
|
|
|
let ty = tcx.type_of(def_id).instantiate_identity();
|
|
if ty.references_error() {
|
|
// If there is already another error, do not emit an error for not using a type parameter.
|
|
return;
|
|
}
|
|
|
|
// Lazily calculated because it is only needed in case of an error.
|
|
let bounded_params = LazyCell::new(|| {
|
|
tcx.explicit_predicates_of(def_id)
|
|
.predicates
|
|
.iter()
|
|
.filter_map(|(predicate, span)| {
|
|
let bounded_ty = match predicate.kind().skip_binder() {
|
|
ty::ClauseKind::Trait(pred) => pred.trait_ref.self_ty(),
|
|
ty::ClauseKind::TypeOutlives(pred) => pred.0,
|
|
_ => return None,
|
|
};
|
|
if let ty::Param(param) = bounded_ty.kind() {
|
|
Some((param.index, span))
|
|
} else {
|
|
None
|
|
}
|
|
})
|
|
// FIXME: This assumes that elaborated `Sized` bounds come first (which does hold at the
|
|
// time of writing). This is a bit fragile since we later use the span to detect elaborated
|
|
// `Sized` bounds. If they came last for example, this would break `Trait + /*elab*/Sized`
|
|
// since it would overwrite the span of the user-written bound. This could be fixed by
|
|
// folding the spans with `Span::to` which requires a bit of effort I think.
|
|
.collect::<FxIndexMap<_, _>>()
|
|
});
|
|
|
|
let mut params_used = DenseBitSet::new_empty(generics.own_params.len());
|
|
for leaf in ty.walk() {
|
|
if let GenericArgKind::Type(leaf_ty) = leaf.unpack()
|
|
&& let ty::Param(param) = leaf_ty.kind()
|
|
{
|
|
debug!("found use of ty param {:?}", param);
|
|
params_used.insert(param.index);
|
|
}
|
|
}
|
|
|
|
for param in &generics.own_params {
|
|
if !params_used.contains(param.index)
|
|
&& let ty::GenericParamDefKind::Type { .. } = param.kind
|
|
{
|
|
let span = tcx.def_span(param.def_id);
|
|
let param_name = Ident::new(param.name, span);
|
|
|
|
// The corresponding predicates are post-`Sized`-elaboration. Therefore we
|
|
// * check for emptiness to detect lone user-written `?Sized` bounds
|
|
// * compare the param span to the pred span to detect lone user-written `Sized` bounds
|
|
let has_explicit_bounds = bounded_params.is_empty()
|
|
|| (*bounded_params).get(¶m.index).is_some_and(|&&pred_sp| pred_sp != span);
|
|
let const_param_help = !has_explicit_bounds;
|
|
|
|
let mut diag = tcx.dcx().create_err(errors::UnusedGenericParameter {
|
|
span,
|
|
param_name,
|
|
param_def_kind: tcx.def_descr(param.def_id),
|
|
help: errors::UnusedGenericParameterHelp::TyAlias { param_name },
|
|
usage_spans: vec![],
|
|
const_param_help,
|
|
});
|
|
diag.code(E0091);
|
|
diag.emit();
|
|
}
|
|
}
|
|
}
|
|
|
|
/// Emit an error for recursive opaque types.
|
|
///
|
|
/// If this is a return `impl Trait`, find the item's return expressions and point at them. For
|
|
/// direct recursion this is enough, but for indirect recursion also point at the last intermediary
|
|
/// `impl Trait`.
|
|
///
|
|
/// If all the return expressions evaluate to `!`, then we explain that the error will go away
|
|
/// after changing it. This can happen when a user uses `panic!()` or similar as a placeholder.
|
|
fn opaque_type_cycle_error(tcx: TyCtxt<'_>, opaque_def_id: LocalDefId) -> ErrorGuaranteed {
|
|
let span = tcx.def_span(opaque_def_id);
|
|
let mut err = struct_span_code_err!(tcx.dcx(), span, E0720, "cannot resolve opaque type");
|
|
|
|
let mut label = false;
|
|
if let Some((def_id, visitor)) = get_owner_return_paths(tcx, opaque_def_id) {
|
|
let typeck_results = tcx.typeck(def_id);
|
|
if visitor
|
|
.returns
|
|
.iter()
|
|
.filter_map(|expr| typeck_results.node_type_opt(expr.hir_id))
|
|
.all(|ty| matches!(ty.kind(), ty::Never))
|
|
{
|
|
let spans = visitor
|
|
.returns
|
|
.iter()
|
|
.filter(|expr| typeck_results.node_type_opt(expr.hir_id).is_some())
|
|
.map(|expr| expr.span)
|
|
.collect::<Vec<Span>>();
|
|
let span_len = spans.len();
|
|
if span_len == 1 {
|
|
err.span_label(spans[0], "this returned value is of `!` type");
|
|
} else {
|
|
let mut multispan: MultiSpan = spans.clone().into();
|
|
for span in spans {
|
|
multispan.push_span_label(span, "this returned value is of `!` type");
|
|
}
|
|
err.span_note(multispan, "these returned values have a concrete \"never\" type");
|
|
}
|
|
err.help("this error will resolve once the item's body returns a concrete type");
|
|
} else {
|
|
let mut seen = FxHashSet::default();
|
|
seen.insert(span);
|
|
err.span_label(span, "recursive opaque type");
|
|
label = true;
|
|
for (sp, ty) in visitor
|
|
.returns
|
|
.iter()
|
|
.filter_map(|e| typeck_results.node_type_opt(e.hir_id).map(|t| (e.span, t)))
|
|
.filter(|(_, ty)| !matches!(ty.kind(), ty::Never))
|
|
{
|
|
#[derive(Default)]
|
|
struct OpaqueTypeCollector {
|
|
opaques: Vec<DefId>,
|
|
closures: Vec<DefId>,
|
|
}
|
|
impl<'tcx> ty::TypeVisitor<TyCtxt<'tcx>> for OpaqueTypeCollector {
|
|
fn visit_ty(&mut self, t: Ty<'tcx>) {
|
|
match *t.kind() {
|
|
ty::Alias(ty::Opaque, ty::AliasTy { def_id: def, .. }) => {
|
|
self.opaques.push(def);
|
|
}
|
|
ty::Closure(def_id, ..) | ty::Coroutine(def_id, ..) => {
|
|
self.closures.push(def_id);
|
|
t.super_visit_with(self);
|
|
}
|
|
_ => t.super_visit_with(self),
|
|
}
|
|
}
|
|
}
|
|
|
|
let mut visitor = OpaqueTypeCollector::default();
|
|
ty.visit_with(&mut visitor);
|
|
for def_id in visitor.opaques {
|
|
let ty_span = tcx.def_span(def_id);
|
|
if !seen.contains(&ty_span) {
|
|
let descr = if ty.is_impl_trait() { "opaque " } else { "" };
|
|
err.span_label(ty_span, format!("returning this {descr}type `{ty}`"));
|
|
seen.insert(ty_span);
|
|
}
|
|
err.span_label(sp, format!("returning here with type `{ty}`"));
|
|
}
|
|
|
|
for closure_def_id in visitor.closures {
|
|
let Some(closure_local_did) = closure_def_id.as_local() else {
|
|
continue;
|
|
};
|
|
let typeck_results = tcx.typeck(closure_local_did);
|
|
|
|
let mut label_match = |ty: Ty<'_>, span| {
|
|
for arg in ty.walk() {
|
|
if let ty::GenericArgKind::Type(ty) = arg.unpack()
|
|
&& let ty::Alias(
|
|
ty::Opaque,
|
|
ty::AliasTy { def_id: captured_def_id, .. },
|
|
) = *ty.kind()
|
|
&& captured_def_id == opaque_def_id.to_def_id()
|
|
{
|
|
err.span_label(
|
|
span,
|
|
format!(
|
|
"{} captures itself here",
|
|
tcx.def_descr(closure_def_id)
|
|
),
|
|
);
|
|
}
|
|
}
|
|
};
|
|
|
|
// Label any closure upvars that capture the opaque
|
|
for capture in typeck_results.closure_min_captures_flattened(closure_local_did)
|
|
{
|
|
label_match(capture.place.ty(), capture.get_path_span(tcx));
|
|
}
|
|
// Label any coroutine locals that capture the opaque
|
|
if tcx.is_coroutine(closure_def_id)
|
|
&& let Some(coroutine_layout) = tcx.mir_coroutine_witnesses(closure_def_id)
|
|
{
|
|
for interior_ty in &coroutine_layout.field_tys {
|
|
label_match(interior_ty.ty, interior_ty.source_info.span);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
if !label {
|
|
err.span_label(span, "cannot resolve opaque type");
|
|
}
|
|
err.emit()
|
|
}
|
|
|
|
pub(super) fn check_coroutine_obligations(
|
|
tcx: TyCtxt<'_>,
|
|
def_id: LocalDefId,
|
|
) -> Result<(), ErrorGuaranteed> {
|
|
debug_assert!(!tcx.is_typeck_child(def_id.to_def_id()));
|
|
|
|
let typeck_results = tcx.typeck(def_id);
|
|
let param_env = tcx.param_env(def_id);
|
|
|
|
debug!(?typeck_results.coroutine_stalled_predicates);
|
|
|
|
let mode = if tcx.next_trait_solver_globally() {
|
|
TypingMode::post_borrowck_analysis(tcx, def_id)
|
|
} else {
|
|
TypingMode::analysis_in_body(tcx, def_id)
|
|
};
|
|
|
|
let infcx = tcx
|
|
.infer_ctxt()
|
|
// typeck writeback gives us predicates with their regions erased.
|
|
// As borrowck already has checked lifetimes, we do not need to do it again.
|
|
.ignoring_regions()
|
|
.build(mode);
|
|
|
|
let ocx = ObligationCtxt::new_with_diagnostics(&infcx);
|
|
for (predicate, cause) in &typeck_results.coroutine_stalled_predicates {
|
|
ocx.register_obligation(Obligation::new(tcx, cause.clone(), param_env, *predicate));
|
|
}
|
|
|
|
let errors = ocx.select_all_or_error();
|
|
debug!(?errors);
|
|
if !errors.is_empty() {
|
|
return Err(infcx.err_ctxt().report_fulfillment_errors(errors));
|
|
}
|
|
|
|
if !tcx.next_trait_solver_globally() {
|
|
// Check that any hidden types found when checking these stalled coroutine obligations
|
|
// are valid.
|
|
for (key, ty) in infcx.take_opaque_types() {
|
|
let hidden_type = infcx.resolve_vars_if_possible(ty);
|
|
let key = infcx.resolve_vars_if_possible(key);
|
|
sanity_check_found_hidden_type(tcx, key, hidden_type)?;
|
|
}
|
|
}
|
|
|
|
Ok(())
|
|
}
|