diff options
Diffstat (limited to 'compiler/rustc_hir_analysis/src')
| -rw-r--r-- | compiler/rustc_hir_analysis/src/check/check.rs | 116 | ||||
| -rw-r--r-- | compiler/rustc_hir_analysis/src/check/wfcheck.rs | 45 | ||||
| -rw-r--r-- | compiler/rustc_hir_analysis/src/errors.rs | 28 | ||||
| -rw-r--r-- | compiler/rustc_hir_analysis/src/hir_ty_lowering/mod.rs | 2 | ||||
| -rw-r--r-- | compiler/rustc_hir_analysis/src/lib.rs | 42 |
5 files changed, 153 insertions, 80 deletions
diff --git a/compiler/rustc_hir_analysis/src/check/check.rs b/compiler/rustc_hir_analysis/src/check/check.rs index 9ed56d7bde5..71a10ad3a0c 100644 --- a/compiler/rustc_hir_analysis/src/check/check.rs +++ b/compiler/rustc_hir_analysis/src/check/check.rs @@ -6,7 +6,7 @@ use rustc_data_structures::unord::{UnordMap, UnordSet}; use rustc_errors::MultiSpan; use rustc_errors::codes::*; use rustc_hir::def::{CtorKind, DefKind}; -use rustc_hir::{Node, intravisit}; +use rustc_hir::{LangItem, Node, intravisit}; use rustc_infer::infer::{RegionVariableOrigin, TyCtxtInferExt}; use rustc_infer::traits::{Obligation, ObligationCauseCode}; use rustc_lint_defs::builtin::{ @@ -27,6 +27,7 @@ use rustc_session::lint::builtin::UNINHABITED_STATIC; use rustc_trait_selection::error_reporting::InferCtxtErrorExt; use rustc_trait_selection::error_reporting::traits::on_unimplemented::OnUnimplementedDirective; use rustc_trait_selection::traits; +use rustc_trait_selection::traits::query::evaluate_obligation::InferCtxtExt; use rustc_type_ir::fold::TypeFoldable; use tracing::{debug, instrument}; use ty::TypingMode; @@ -87,89 +88,76 @@ fn allowed_union_or_unsafe_field<'tcx>( typing_env: ty::TypingEnv<'tcx>, span: Span, ) -> bool { - // We don't just accept all !needs_drop fields, due to semver concerns. - let allowed = match ty.kind() { - ty::Ref(..) => true, // references never drop (even mutable refs, which are non-Copy and hence fail the later check) - ty::Tuple(tys) => { - // allow tuples of allowed types - tys.iter().all(|ty| allowed_union_or_unsafe_field(tcx, ty, typing_env, span)) - } - ty::Array(elem, _len) => { - // Like `Copy`, we do *not* special-case length 0. - allowed_union_or_unsafe_field(tcx, *elem, typing_env, span) - } - _ => { - // Fallback case: allow `ManuallyDrop` and things that are `Copy`, - // also no need to report an error if the type is unresolved. - ty.ty_adt_def().is_some_and(|adt_def| adt_def.is_manually_drop()) - || tcx.type_is_copy_modulo_regions(typing_env, ty) - || ty.references_error() - } - }; - if allowed && ty.needs_drop(tcx, typing_env) { - // This should never happen. But we can get here e.g. in case of name resolution errors. - tcx.dcx() - .span_delayed_bug(span, "we should never accept maybe-dropping union or unsafe fields"); + // HACK (not that bad of a hack don't worry): Some codegen tests don't even define proper + // impls for `Copy`. Let's short-circuit here for this validity check, since a lot of them + // use unions. We should eventually fix all the tests to define that lang item or use + // minicore stubs. + if ty.is_trivially_pure_clone_copy() { + return true; } - allowed + // If `BikeshedGuaranteedNoDrop` is not defined in a `#[no_core]` test, fall back to `Copy`. + // This is an underapproximation of `BikeshedGuaranteedNoDrop`, + let def_id = tcx + .lang_items() + .get(LangItem::BikeshedGuaranteedNoDrop) + .unwrap_or_else(|| tcx.require_lang_item(LangItem::Copy, Some(span))); + let Ok(ty) = tcx.try_normalize_erasing_regions(typing_env, ty) else { + tcx.dcx().span_delayed_bug(span, "could not normalize field type"); + return true; + }; + let (infcx, param_env) = tcx.infer_ctxt().build_with_typing_env(typing_env); + infcx.predicate_must_hold_modulo_regions(&Obligation::new( + tcx, + ObligationCause::dummy_with_span(span), + param_env, + ty::TraitRef::new(tcx, def_id, [ty]), + )) } /// Check that the fields of the `union` do not need dropping. fn check_union_fields(tcx: TyCtxt<'_>, span: Span, item_def_id: LocalDefId) -> bool { - let item_type = tcx.type_of(item_def_id).instantiate_identity(); - if let ty::Adt(def, args) = item_type.kind() { - assert!(def.is_union()); - - let typing_env = ty::TypingEnv::non_body_analysis(tcx, item_def_id); - for field in &def.non_enum_variant().fields { - let Ok(field_ty) = tcx.try_normalize_erasing_regions(typing_env, field.ty(tcx, args)) - else { - tcx.dcx().span_delayed_bug(span, "could not normalize field type"); - continue; - }; + let def = tcx.adt_def(item_def_id); + assert!(def.is_union()); - if !allowed_union_or_unsafe_field(tcx, field_ty, typing_env, span) { - let (field_span, ty_span) = match tcx.hir().get_if_local(field.did) { - // We are currently checking the type this field came from, so it must be local. - Some(Node::Field(field)) => (field.span, field.ty.span), - _ => unreachable!("mir field has to correspond to hir field"), - }; - tcx.dcx().emit_err(errors::InvalidUnionField { - field_span, - sugg: errors::InvalidUnionFieldSuggestion { - lo: ty_span.shrink_to_lo(), - hi: ty_span.shrink_to_hi(), - }, - note: (), - }); - return false; - } + let typing_env = ty::TypingEnv::non_body_analysis(tcx, item_def_id); + let args = ty::GenericArgs::identity_for_item(tcx, item_def_id); + + for field in &def.non_enum_variant().fields { + if !allowed_union_or_unsafe_field(tcx, field.ty(tcx, args), typing_env, span) { + let (field_span, ty_span) = match tcx.hir().get_if_local(field.did) { + // We are currently checking the type this field came from, so it must be local. + Some(Node::Field(field)) => (field.span, field.ty.span), + _ => unreachable!("mir field has to correspond to hir field"), + }; + tcx.dcx().emit_err(errors::InvalidUnionField { + field_span, + sugg: errors::InvalidUnionFieldSuggestion { + lo: ty_span.shrink_to_lo(), + hi: ty_span.shrink_to_hi(), + }, + note: (), + }); + return false; } - } else { - span_bug!(span, "unions must be ty::Adt, but got {:?}", item_type.kind()); } + true } /// Check that the unsafe fields do not need dropping. fn check_unsafe_fields(tcx: TyCtxt<'_>, item_def_id: LocalDefId) { let span = tcx.def_span(item_def_id); - let item_type = tcx.type_of(item_def_id).instantiate_identity(); - let ty::Adt(def, args) = item_type.kind() else { - span_bug!(span, "structs/enums must be ty::Adt, but got {:?}", item_type.kind()); - }; + let def = tcx.adt_def(item_def_id); + let typing_env = ty::TypingEnv::non_body_analysis(tcx, item_def_id); + let args = ty::GenericArgs::identity_for_item(tcx, item_def_id); + for field in def.all_fields() { if !field.safety.is_unsafe() { continue; } - let Ok(field_ty) = tcx.try_normalize_erasing_regions(typing_env, field.ty(tcx, args)) - else { - tcx.dcx().span_delayed_bug(span, "could not normalize field type"); - continue; - }; - if !allowed_union_or_unsafe_field(tcx, field_ty, typing_env, span) { + if !allowed_union_or_unsafe_field(tcx, field.ty(tcx, args), typing_env, span) { let hir::Node::Field(field) = tcx.hir_node_by_def_id(field.did.expect_local()) else { unreachable!("field has to correspond to hir field") }; diff --git a/compiler/rustc_hir_analysis/src/check/wfcheck.rs b/compiler/rustc_hir_analysis/src/check/wfcheck.rs index 1689437ffb0..4218f4ef0c1 100644 --- a/compiler/rustc_hir_analysis/src/check/wfcheck.rs +++ b/compiler/rustc_hir_analysis/src/check/wfcheck.rs @@ -12,6 +12,7 @@ use rustc_hir::lang_items::LangItem; use rustc_hir::{AmbigArg, ItemKind}; use rustc_infer::infer::outlives::env::OutlivesEnvironment; use rustc_infer::infer::{self, InferCtxt, TyCtxtInferExt}; +use rustc_lint_defs::builtin::SUPERTRAIT_ITEM_SHADOWING_DEFINITION; use rustc_macros::LintDiagnostic; use rustc_middle::mir::interpret::ErrorHandled; use rustc_middle::query::Providers; @@ -388,7 +389,12 @@ fn check_trait_item<'tcx>( hir::TraitItemKind::Type(_bounds, Some(ty)) => (None, ty.span), _ => (None, trait_item.span), }; + check_dyn_incompatible_self_trait_by_name(tcx, trait_item); + + // Check that an item definition in a subtrait is shadowing a supertrait item. + lint_item_shadowing_supertrait_item(tcx, def_id); + let mut res = check_associated_item(tcx, def_id, span, method_sig); if matches!(trait_item.kind, hir::TraitItemKind::Fn(..)) { @@ -898,6 +904,45 @@ fn check_dyn_incompatible_self_trait_by_name(tcx: TyCtxt<'_>, item: &hir::TraitI } } +fn lint_item_shadowing_supertrait_item<'tcx>(tcx: TyCtxt<'tcx>, trait_item_def_id: LocalDefId) { + let item_name = tcx.item_name(trait_item_def_id.to_def_id()); + let trait_def_id = tcx.local_parent(trait_item_def_id); + + let shadowed: Vec<_> = traits::supertrait_def_ids(tcx, trait_def_id.to_def_id()) + .skip(1) + .flat_map(|supertrait_def_id| { + tcx.associated_items(supertrait_def_id).filter_by_name_unhygienic(item_name) + }) + .collect(); + if !shadowed.is_empty() { + let shadowee = if let [shadowed] = shadowed[..] { + errors::SupertraitItemShadowee::Labeled { + span: tcx.def_span(shadowed.def_id), + supertrait: tcx.item_name(shadowed.trait_container(tcx).unwrap()), + } + } else { + let (traits, spans): (Vec<_>, Vec<_>) = shadowed + .iter() + .map(|item| { + (tcx.item_name(item.trait_container(tcx).unwrap()), tcx.def_span(item.def_id)) + }) + .unzip(); + errors::SupertraitItemShadowee::Several { traits: traits.into(), spans: spans.into() } + }; + + tcx.emit_node_span_lint( + SUPERTRAIT_ITEM_SHADOWING_DEFINITION, + tcx.local_def_id_to_hir_id(trait_item_def_id), + tcx.def_span(trait_item_def_id), + errors::SupertraitItemShadowing { + item: item_name, + subtrait: tcx.item_name(trait_def_id.to_def_id()), + shadowee, + }, + ); + } +} + fn check_impl_item<'tcx>( tcx: TyCtxt<'tcx>, impl_item: &'tcx hir::ImplItem<'tcx>, diff --git a/compiler/rustc_hir_analysis/src/errors.rs b/compiler/rustc_hir_analysis/src/errors.rs index 1574506de60..14ea10461cb 100644 --- a/compiler/rustc_hir_analysis/src/errors.rs +++ b/compiler/rustc_hir_analysis/src/errors.rs @@ -3,7 +3,8 @@ use rustc_abi::ExternAbi; use rustc_errors::codes::*; use rustc_errors::{ - Applicability, Diag, DiagCtxtHandle, Diagnostic, EmissionGuarantee, Level, MultiSpan, + Applicability, Diag, DiagCtxtHandle, DiagSymbolList, Diagnostic, EmissionGuarantee, Level, + MultiSpan, }; use rustc_macros::{Diagnostic, LintDiagnostic, Subdiagnostic}; use rustc_middle::ty::Ty; @@ -1733,3 +1734,28 @@ pub(crate) struct RegisterTypeUnstable<'a> { pub span: Span, pub ty: Ty<'a>, } + +#[derive(LintDiagnostic)] +#[diag(hir_analysis_supertrait_item_shadowing)] +pub(crate) struct SupertraitItemShadowing { + pub item: Symbol, + pub subtrait: Symbol, + #[subdiagnostic] + pub shadowee: SupertraitItemShadowee, +} + +#[derive(Subdiagnostic)] +pub(crate) enum SupertraitItemShadowee { + #[note(hir_analysis_supertrait_item_shadowee)] + Labeled { + #[primary_span] + span: Span, + supertrait: Symbol, + }, + #[note(hir_analysis_supertrait_item_multiple_shadowee)] + Several { + #[primary_span] + spans: MultiSpan, + traits: DiagSymbolList, + }, +} diff --git a/compiler/rustc_hir_analysis/src/hir_ty_lowering/mod.rs b/compiler/rustc_hir_analysis/src/hir_ty_lowering/mod.rs index c6e47a804dc..88323db6dda 100644 --- a/compiler/rustc_hir_analysis/src/hir_ty_lowering/mod.rs +++ b/compiler/rustc_hir_analysis/src/hir_ty_lowering/mod.rs @@ -2161,7 +2161,7 @@ impl<'tcx> dyn HirTyLowerer<'tcx> + '_ { did, path.segments.last().unwrap(), ); - ty::Const::new_value(tcx, ty::ValTree::zst(), Ty::new_fn_def(tcx, did, args)) + ty::Const::zero_sized(tcx, Ty::new_fn_def(tcx, did, args)) } // Exhaustive match to be clear about what exactly we're considering to be diff --git a/compiler/rustc_hir_analysis/src/lib.rs b/compiler/rustc_hir_analysis/src/lib.rs index 323b912ca18..8a529e9c686 100644 --- a/compiler/rustc_hir_analysis/src/lib.rs +++ b/compiler/rustc_hir_analysis/src/lib.rs @@ -122,28 +122,42 @@ fn require_c_abi_if_c_variadic( const UNSTABLE_EXPLAIN: &str = "using calling conventions other than `C` or `cdecl` for varargs functions is unstable"; + // ABIs which can stably use varargs if !decl.c_variadic || matches!(abi, ExternAbi::C { .. } | ExternAbi::Cdecl { .. }) { return; } + // ABIs with feature-gated stability let extended_abi_support = tcx.features().extended_varargs_abi_support(); - let conventions = match (extended_abi_support, abi.supports_varargs()) { - // User enabled additional ABI support for varargs and function ABI matches those ones. - (true, true) => return, + let extern_system_varargs = tcx.features().extern_system_varargs(); - // Using this ABI would be ok, if the feature for additional ABI support was enabled. - // Return CONVENTIONS_STABLE, because we want the other error to look the same. - (false, true) => { - feature_err(&tcx.sess, sym::extended_varargs_abi_support, span, UNSTABLE_EXPLAIN) - .emit(); - CONVENTIONS_STABLE - } - - (false, false) => CONVENTIONS_STABLE, - (true, false) => CONVENTIONS_UNSTABLE, + // If the feature gate has been enabled, we can stop here + if extern_system_varargs && let ExternAbi::System { .. } = abi { + return; + }; + if extended_abi_support && abi.supports_varargs() { + return; }; - tcx.dcx().emit_err(errors::VariadicFunctionCompatibleConvention { span, conventions }); + // Looks like we need to pick an error to emit. + // Is there any feature which we could have enabled to make this work? + match abi { + ExternAbi::System { .. } => { + feature_err(&tcx.sess, sym::extern_system_varargs, span, UNSTABLE_EXPLAIN) + } + abi if abi.supports_varargs() => { + feature_err(&tcx.sess, sym::extended_varargs_abi_support, span, UNSTABLE_EXPLAIN) + } + _ => tcx.dcx().create_err(errors::VariadicFunctionCompatibleConvention { + span, + conventions: if tcx.sess.opts.unstable_features.is_nightly_build() { + CONVENTIONS_UNSTABLE + } else { + CONVENTIONS_STABLE + }, + }), + } + .emit(); } pub fn provide(providers: &mut Providers) { |