diff options
Diffstat (limited to '')
| -rw-r--r-- | compiler/rustc_hir_analysis/src/check/wfcheck.rs (renamed from compiler/rustc_typeck/src/check/wfcheck.rs) | 367 |
1 files changed, 192 insertions, 175 deletions
diff --git a/compiler/rustc_typeck/src/check/wfcheck.rs b/compiler/rustc_hir_analysis/src/check/wfcheck.rs index d0334cd0d..a23575004 100644 --- a/compiler/rustc_typeck/src/check/wfcheck.rs +++ b/compiler/rustc_hir_analysis/src/check/wfcheck.rs @@ -1,5 +1,5 @@ -use crate::check::regionck::OutlivesEnvironmentExt; use crate::constrained_generic_params::{identify_constrained_generic_params, Parameter}; +use hir::def::DefKind; use rustc_ast as ast; use rustc_data_structures::fx::{FxHashMap, FxHashSet}; use rustc_errors::{pluralize, struct_span_err, Applicability, DiagnosticBuilder, ErrorGuaranteed}; @@ -10,22 +10,21 @@ use rustc_hir::ItemKind; use rustc_infer::infer::outlives::env::{OutlivesEnvironment, RegionBoundPairs}; use rustc_infer::infer::outlives::obligations::TypeOutlives; use rustc_infer::infer::{self, InferCtxt, TyCtxtInferExt}; -use rustc_infer::traits::Normalized; +use rustc_middle::mir::ConstraintCategory; use rustc_middle::ty::query::Providers; -use rustc_middle::ty::subst::{GenericArgKind, InternalSubsts, Subst}; use rustc_middle::ty::trait_def::TraitSpecializationKind; use rustc_middle::ty::{ self, AdtKind, DefIdTree, GenericParamDefKind, ToPredicate, Ty, TyCtxt, TypeFoldable, TypeSuperVisitable, TypeVisitable, TypeVisitor, }; +use rustc_middle::ty::{GenericArgKind, InternalSubsts}; use rustc_session::parse::feature_err; use rustc_span::symbol::{sym, Ident, Symbol}; use rustc_span::{Span, DUMMY_SP}; use rustc_trait_selection::autoderef::Autoderef; -use rustc_trait_selection::traits::error_reporting::InferCtxtExt; +use rustc_trait_selection::traits::error_reporting::TypeErrCtxtExt; +use rustc_trait_selection::traits::outlives_bounds::InferCtxtExt as _; use rustc_trait_selection::traits::query::evaluate_obligation::InferCtxtExt as _; -use rustc_trait_selection::traits::query::normalize::AtExt; -use rustc_trait_selection::traits::query::NoSolution; use rustc_trait_selection::traits::{ self, ObligationCause, ObligationCauseCode, ObligationCtxt, WellFormedLoc, }; @@ -72,9 +71,11 @@ impl<'tcx> WfCheckingCtxt<'_, 'tcx> { ) { let cause = traits::ObligationCause::new(span, self.body_id, ObligationCauseCode::WellFormed(loc)); + // for a type to be WF, we do not need to check if const trait predicates satisfy. + let param_env = self.param_env.without_const(); self.ocx.register_obligation(traits::Obligation::new( cause, - self.param_env, + param_env, ty::Binder::dummy(ty::PredicateKind::WellFormed(arg)).to_predicate(self.tcx()), )); } @@ -86,31 +87,35 @@ pub(super) fn enter_wf_checking_ctxt<'tcx, F>( body_def_id: LocalDefId, f: F, ) where - F: for<'a> FnOnce(&WfCheckingCtxt<'a, 'tcx>) -> FxHashSet<Ty<'tcx>>, + F: for<'a> FnOnce(&WfCheckingCtxt<'a, 'tcx>), { let param_env = tcx.param_env(body_def_id); let body_id = tcx.hir().local_def_id_to_hir_id(body_def_id); - tcx.infer_ctxt().enter(|ref infcx| { - let ocx = ObligationCtxt::new(infcx); - let mut wfcx = WfCheckingCtxt { ocx, span, body_id, param_env }; + let infcx = &tcx.infer_ctxt().build(); + let ocx = ObligationCtxt::new(infcx); - if !tcx.features().trivial_bounds { - wfcx.check_false_global_bounds() - } - let wf_tys = f(&mut wfcx); - let errors = wfcx.select_all_or_error(); - if !errors.is_empty() { - infcx.report_fulfillment_errors(&errors, None, false); - return; - } + let assumed_wf_types = ocx.assumed_wf_types(param_env, span, body_def_id); - let mut outlives_environment = OutlivesEnvironment::new(param_env); - outlives_environment.add_implied_bounds(infcx, wf_tys, body_id); - infcx.check_region_obligations_and_report_errors(body_def_id, &outlives_environment); - }) + let mut wfcx = WfCheckingCtxt { ocx, span, body_id, param_env }; + + if !tcx.features().trivial_bounds { + wfcx.check_false_global_bounds() + } + f(&mut wfcx); + let errors = wfcx.select_all_or_error(); + if !errors.is_empty() { + infcx.err_ctxt().report_fulfillment_errors(&errors, None, false); + return; + } + + let implied_bounds = infcx.implied_bounds_tys(param_env, body_id, assumed_wf_types); + let outlives_environment = + OutlivesEnvironment::with_bounds(param_env, Some(infcx), implied_bounds); + + infcx.check_region_obligations_and_report_errors(body_def_id, &outlives_environment); } -fn check_well_formed(tcx: TyCtxt<'_>, def_id: LocalDefId) { +fn check_well_formed(tcx: TyCtxt<'_>, def_id: hir::OwnerId) { let node = tcx.hir().expect_owner(def_id); match node { hir::OwnerNode::Crate(_) => {} @@ -142,10 +147,10 @@ fn check_well_formed(tcx: TyCtxt<'_>, def_id: LocalDefId) { /// the types first. #[instrument(skip(tcx), level = "debug")] fn check_item<'tcx>(tcx: TyCtxt<'tcx>, item: &'tcx hir::Item<'tcx>) { - let def_id = item.def_id; + let def_id = item.owner_id.def_id; debug!( - ?item.def_id, + ?item.owner_id, item.name = ? tcx.def_path_str(def_id.to_def_id()) ); @@ -169,7 +174,7 @@ fn check_item<'tcx>(tcx: TyCtxt<'tcx>, item: &'tcx hir::Item<'tcx>) { // for `T` hir::ItemKind::Impl(ref impl_) => { let is_auto = tcx - .impl_trait_ref(item.def_id) + .impl_trait_ref(def_id) .map_or(false, |trait_ref| tcx.trait_is_auto(trait_ref.def_id)); if let (hir::Defaultness::Default { .. }, true) = (impl_.defaultness, is_auto) { let sp = impl_.of_trait.as_ref().map_or(item.span, |t| t.path.span); @@ -205,13 +210,13 @@ fn check_item<'tcx>(tcx: TyCtxt<'tcx>, item: &'tcx hir::Item<'tcx>) { } } hir::ItemKind::Fn(ref sig, ..) => { - check_item_fn(tcx, item.def_id, item.ident, item.span, sig.decl); + check_item_fn(tcx, def_id, item.ident, item.span, sig.decl); } hir::ItemKind::Static(ty, ..) => { - check_item_type(tcx, item.def_id, ty.span, false); + check_item_type(tcx, def_id, ty.span, false); } hir::ItemKind::Const(ty, ..) => { - check_item_type(tcx, item.def_id, ty.span, false); + check_item_type(tcx, def_id, ty.span, false); } hir::ItemKind::Struct(ref struct_def, ref ast_generics) => { check_type_defn(tcx, item, false, |wfcx| vec![wfcx.non_enum_variant(struct_def)]); @@ -241,24 +246,24 @@ fn check_item<'tcx>(tcx: TyCtxt<'tcx>, item: &'tcx hir::Item<'tcx>) { } fn check_foreign_item(tcx: TyCtxt<'_>, item: &hir::ForeignItem<'_>) { - let def_id = item.def_id; + let def_id = item.owner_id.def_id; debug!( - ?item.def_id, + ?item.owner_id, item.name = ? tcx.def_path_str(def_id.to_def_id()) ); match item.kind { hir::ForeignItemKind::Fn(decl, ..) => { - check_item_fn(tcx, item.def_id, item.ident, item.span, decl) + check_item_fn(tcx, def_id, item.ident, item.span, decl) } - hir::ForeignItemKind::Static(ty, ..) => check_item_type(tcx, item.def_id, ty.span, true), + hir::ForeignItemKind::Static(ty, ..) => check_item_type(tcx, def_id, ty.span, true), hir::ForeignItemKind::Type => (), } } fn check_trait_item(tcx: TyCtxt<'_>, trait_item: &hir::TraitItem<'_>) { - let def_id = trait_item.def_id; + let def_id = trait_item.owner_id.def_id; let (method_sig, span) = match trait_item.kind { hir::TraitItemKind::Fn(ref sig, _) => (Some(sig), trait_item.span), @@ -266,11 +271,11 @@ fn check_trait_item(tcx: TyCtxt<'_>, trait_item: &hir::TraitItem<'_>) { _ => (None, trait_item.span), }; check_object_unsafe_self_trait_by_name(tcx, trait_item); - check_associated_item(tcx, trait_item.def_id, span, method_sig); + check_associated_item(tcx, def_id, span, method_sig); let encl_trait_def_id = tcx.local_parent(def_id); let encl_trait = tcx.hir().expect_item(encl_trait_def_id); - let encl_trait_def_id = encl_trait.def_id.to_def_id(); + let encl_trait_def_id = encl_trait.owner_id.to_def_id(); let fn_lang_item_name = if Some(encl_trait_def_id) == tcx.lang_items().fn_trait() { Some("fn") } else if Some(encl_trait_def_id) == tcx.lang_items().fn_mut_trait() { @@ -343,7 +348,7 @@ fn check_gat_where_clauses(tcx: TyCtxt<'_>, associated_items: &[hir::TraitItemRe loop { let mut should_continue = false; for gat_item in associated_items { - let gat_def_id = gat_item.id.def_id; + let gat_def_id = gat_item.id.owner_id; let gat_item = tcx.associated_item(gat_def_id); // If this item is not an assoc ty, or has no substs, then it's not a GAT if gat_item.kind != ty::AssocKind::Type { @@ -360,7 +365,7 @@ fn check_gat_where_clauses(tcx: TyCtxt<'_>, associated_items: &[hir::TraitItemRe // constrains the GAT with individually. let mut new_required_bounds: Option<FxHashSet<ty::Predicate<'_>>> = None; for item in associated_items { - let item_def_id = item.id.def_id; + let item_def_id = item.id.owner_id; // Skip our own GAT, since it does not constrain itself at all. if item_def_id == gat_def_id { continue; @@ -383,11 +388,11 @@ fn check_gat_where_clauses(tcx: TyCtxt<'_>, associated_items: &[hir::TraitItemRe tcx, param_env, item_hir_id, - sig.output(), + sig.inputs_and_output, // We also assume that all of the function signature's parameter types // are well formed. &sig.inputs().iter().copied().collect(), - gat_def_id, + gat_def_id.def_id, gat_generics, ) } @@ -410,7 +415,7 @@ fn check_gat_where_clauses(tcx: TyCtxt<'_>, associated_items: &[hir::TraitItemRe .copied() .collect::<Vec<_>>(), &FxHashSet::default(), - gat_def_id, + gat_def_id.def_id, gat_generics, ) } @@ -450,7 +455,7 @@ fn check_gat_where_clauses(tcx: TyCtxt<'_>, associated_items: &[hir::TraitItemRe } for (gat_def_id, required_bounds) in required_bounds_by_item { - let gat_item_hir = tcx.hir().expect_trait_item(gat_def_id); + let gat_item_hir = tcx.hir().expect_trait_item(gat_def_id.def_id); debug!(?required_bounds); let param_env = tcx.param_env(gat_def_id); let gat_hir = gat_item_hir.hir_id(); @@ -658,7 +663,7 @@ fn ty_known_to_outlive<'tcx>( resolve_regions_with_wf_tys(tcx, id, param_env, &wf_tys, |infcx, region_bound_pairs| { let origin = infer::RelateParamBound(DUMMY_SP, ty, None); let outlives = &mut TypeOutlives::new(infcx, tcx, region_bound_pairs, None, param_env); - outlives.type_must_outlive(origin, ty, region); + outlives.type_must_outlive(origin, ty, region, ConstraintCategory::BoringNoLocation); }) } @@ -676,7 +681,12 @@ fn region_known_to_outlive<'tcx>( use rustc_infer::infer::outlives::obligations::TypeOutlivesDelegate; let origin = infer::RelateRegionParamBound(DUMMY_SP); // `region_a: region_b` -> `region_b <= region_a` - infcx.push_sub_region_constraint(origin, region_b, region_a); + infcx.push_sub_region_constraint( + origin, + region_b, + region_a, + ConstraintCategory::BoringNoLocation, + ); }) } @@ -688,26 +698,32 @@ fn resolve_regions_with_wf_tys<'tcx>( id: hir::HirId, param_env: ty::ParamEnv<'tcx>, wf_tys: &FxHashSet<Ty<'tcx>>, - add_constraints: impl for<'a> FnOnce(&'a InferCtxt<'a, 'tcx>, &'a RegionBoundPairs<'tcx>), + add_constraints: impl for<'a> FnOnce(&'a InferCtxt<'tcx>, &'a RegionBoundPairs<'tcx>), ) -> bool { // Unfortunately, we have to use a new `InferCtxt` each call, because // region constraints get added and solved there and we need to test each // call individually. - tcx.infer_ctxt().enter(|infcx| { - let mut outlives_environment = OutlivesEnvironment::new(param_env); - outlives_environment.add_implied_bounds(&infcx, wf_tys.clone(), id); - let region_bound_pairs = outlives_environment.region_bound_pairs(); + let infcx = tcx.infer_ctxt().build(); + let outlives_environment = OutlivesEnvironment::with_bounds( + param_env, + Some(&infcx), + infcx.implied_bounds_tys(param_env, id, wf_tys.clone()), + ); + let region_bound_pairs = outlives_environment.region_bound_pairs(); - add_constraints(&infcx, region_bound_pairs); + add_constraints(&infcx, region_bound_pairs); - let errors = infcx.resolve_regions(&outlives_environment); + infcx.process_registered_region_obligations( + outlives_environment.region_bound_pairs(), + param_env, + ); + let errors = infcx.resolve_regions(&outlives_environment); - debug!(?errors, "errors"); + debug!(?errors, "errors"); - // If we were able to prove that the type outlives the region without - // an error, it must be because of the implied or explicit bounds... - errors.is_empty() - }) + // If we were able to prove that the type outlives the region without + // an error, it must be because of the implied or explicit bounds... + errors.is_empty() } /// TypeVisitor that looks for uses of GATs like @@ -761,7 +777,7 @@ impl<'tcx> TypeVisitor<'tcx> for GATSubstCollector<'tcx> { fn could_be_self(trait_def_id: LocalDefId, ty: &hir::Ty<'_>) -> bool { match ty.kind { hir::TyKind::TraitObject([trait_ref], ..) => match trait_ref.trait_ref.path.segments { - [s] => s.res.and_then(|r| r.opt_def_id()) == Some(trait_def_id.to_def_id()), + [s] => s.res.opt_def_id() == Some(trait_def_id.to_def_id()), _ => false, }, _ => false, @@ -772,9 +788,9 @@ fn could_be_self(trait_def_id: LocalDefId, ty: &hir::Ty<'_>) -> bool { /// When this is done, suggest using `Self` instead. fn check_object_unsafe_self_trait_by_name(tcx: TyCtxt<'_>, item: &hir::TraitItem<'_>) { let (trait_name, trait_def_id) = - match tcx.hir().get_by_def_id(tcx.hir().get_parent_item(item.hir_id())) { + match tcx.hir().get_by_def_id(tcx.hir().get_parent_item(item.hir_id()).def_id) { hir::Node::Item(item) => match item.kind { - hir::ItemKind::Trait(..) => (item.ident, item.def_id), + hir::ItemKind::Trait(..) => (item.ident, item.owner_id), _ => return, }, _ => return, @@ -782,18 +798,18 @@ fn check_object_unsafe_self_trait_by_name(tcx: TyCtxt<'_>, item: &hir::TraitItem let mut trait_should_be_self = vec![]; match &item.kind { hir::TraitItemKind::Const(ty, _) | hir::TraitItemKind::Type(_, Some(ty)) - if could_be_self(trait_def_id, ty) => + if could_be_self(trait_def_id.def_id, ty) => { trait_should_be_self.push(ty.span) } hir::TraitItemKind::Fn(sig, _) => { for ty in sig.decl.inputs { - if could_be_self(trait_def_id, ty) { + if could_be_self(trait_def_id.def_id, ty) { trait_should_be_self.push(ty.span); } } match sig.decl.output { - hir::FnRetTy::Return(ty) if could_be_self(trait_def_id, ty) => { + hir::FnRetTy::Return(ty) if could_be_self(trait_def_id.def_id, ty) => { trait_should_be_self.push(ty.span); } _ => {} @@ -822,16 +838,14 @@ fn check_object_unsafe_self_trait_by_name(tcx: TyCtxt<'_>, item: &hir::TraitItem } fn check_impl_item(tcx: TyCtxt<'_>, impl_item: &hir::ImplItem<'_>) { - let def_id = impl_item.def_id; - let (method_sig, span) = match impl_item.kind { hir::ImplItemKind::Fn(ref sig, _) => (Some(sig), impl_item.span), // Constrain binding and overflow error spans to `<Ty>` in `type foo = <Ty>`. - hir::ImplItemKind::TyAlias(ty) if ty.span != DUMMY_SP => (None, ty.span), + hir::ImplItemKind::Type(ty) if ty.span != DUMMY_SP => (None, ty.span), _ => (None, impl_item.span), }; - check_associated_item(tcx, def_id, span, method_sig); + check_associated_item(tcx, impl_item.owner_id.def_id, span, method_sig); } fn check_param_wf(tcx: TyCtxt<'_>, param: &hir::GenericParam<'_>) { @@ -965,7 +979,7 @@ fn check_param_wf(tcx: TyCtxt<'_>, param: &hir::GenericParam<'_>) { } } -#[tracing::instrument(level = "debug", skip(tcx, span, sig_if_method))] +#[instrument(level = "debug", skip(tcx, span, sig_if_method))] fn check_associated_item( tcx: TyCtxt<'_>, item_id: LocalDefId, @@ -976,15 +990,9 @@ fn check_associated_item( enter_wf_checking_ctxt(tcx, span, item_id, |wfcx| { let item = tcx.associated_item(item_id); - let (mut implied_bounds, self_ty) = match item.container { - ty::TraitContainer => (FxHashSet::default(), tcx.types.self_param), - ty::ImplContainer => { - let def_id = item.container_id(tcx); - ( - impl_implied_bounds(tcx, wfcx.param_env, def_id.expect_local(), span), - tcx.type_of(def_id), - ) - } + let self_ty = match item.container { + ty::TraitContainer => tcx.types.self_param, + ty::ImplContainer => tcx.type_of(item.container_id(tcx)), }; match item.kind { @@ -1002,7 +1010,6 @@ fn check_associated_item( sig, hir_sig.decl, item.def_id.expect_local(), - &mut implied_bounds, ); check_method_receiver(wfcx, hir_sig, item, self_ty); } @@ -1017,8 +1024,6 @@ fn check_associated_item( } } } - - implied_bounds }) } @@ -1040,9 +1045,11 @@ fn check_type_defn<'tcx, F>( ) where F: FnMut(&WfCheckingCtxt<'_, 'tcx>) -> Vec<AdtVariant<'tcx>>, { - enter_wf_checking_ctxt(tcx, item.span, item.def_id, |wfcx| { + let _ = tcx.representability(item.owner_id.def_id); + + enter_wf_checking_ctxt(tcx, item.span, item.owner_id.def_id, |wfcx| { let variants = lookup_fields(wfcx); - let packed = tcx.adt_def(item.def_id).repr().packed(); + let packed = tcx.adt_def(item.owner_id).repr().packed(); for variant in &variants { // All field types must be well-formed. @@ -1066,7 +1073,7 @@ fn check_type_defn<'tcx, F>( // Just treat unresolved type expression as if it needs drop. true } else { - ty.needs_drop(tcx, tcx.param_env(item.def_id)) + ty.needs_drop(tcx, tcx.param_env(item.owner_id)) } } }; @@ -1098,8 +1105,6 @@ fn check_type_defn<'tcx, F>( // Explicit `enum` discriminant values must const-evaluate successfully. if let Some(discr_def_id) = variant.explicit_discr { - let discr_substs = InternalSubsts::identity_for_item(tcx, discr_def_id.to_def_id()); - let cause = traits::ObligationCause::new( tcx.def_span(discr_def_id), wfcx.body_id, @@ -1108,31 +1113,28 @@ fn check_type_defn<'tcx, F>( wfcx.register_obligation(traits::Obligation::new( cause, wfcx.param_env, - ty::Binder::dummy(ty::PredicateKind::ConstEvaluatable(ty::Unevaluated::new( - ty::WithOptConstParam::unknown(discr_def_id.to_def_id()), - discr_substs, - ))) + ty::Binder::dummy(ty::PredicateKind::ConstEvaluatable( + ty::Const::from_anon_const(tcx, discr_def_id), + )) .to_predicate(tcx), )); } } - check_where_clauses(wfcx, item.span, item.def_id); - - // No implied bounds in a struct definition. - FxHashSet::default() + check_where_clauses(wfcx, item.span, item.owner_id.def_id); }); } #[instrument(skip(tcx, item))] fn check_trait(tcx: TyCtxt<'_>, item: &hir::Item<'_>) { - debug!(?item.def_id); + debug!(?item.owner_id); - let trait_def = tcx.trait_def(item.def_id); + let def_id = item.owner_id.def_id; + let trait_def = tcx.trait_def(def_id); if trait_def.is_marker || matches!(trait_def.specialization_kind, TraitSpecializationKind::Marker) { - for associated_def_id in &*tcx.associated_item_def_ids(item.def_id) { + for associated_def_id in &*tcx.associated_item_def_ids(def_id) { struct_span_err!( tcx.sess, tcx.def_span(*associated_def_id), @@ -1143,10 +1145,8 @@ fn check_trait(tcx: TyCtxt<'_>, item: &hir::Item<'_>) { } } - enter_wf_checking_ctxt(tcx, item.span, item.def_id, |wfcx| { - check_where_clauses(wfcx, item.span, item.def_id); - - FxHashSet::default() + enter_wf_checking_ctxt(tcx, item.span, def_id, |wfcx| { + check_where_clauses(wfcx, item.span, def_id) }); // Only check traits, don't check trait aliases @@ -1186,9 +1186,7 @@ fn check_item_fn( ) { enter_wf_checking_ctxt(tcx, span, def_id, |wfcx| { let sig = tcx.fn_sig(def_id); - let mut implied_bounds = FxHashSet::default(); - check_fn_or_method(wfcx, ident.span, sig, decl, def_id, &mut implied_bounds); - implied_bounds + check_fn_or_method(wfcx, ident.span, sig, decl, def_id); }) } @@ -1231,13 +1229,10 @@ fn check_item_type(tcx: TyCtxt<'_>, item_id: LocalDefId, ty_span: Span, allow_fo tcx.require_lang_item(LangItem::Sync, Some(ty_span)), ); } - - // No implied bounds in a const, etc. - FxHashSet::default() }); } -#[tracing::instrument(level = "debug", skip(tcx, ast_self_ty, ast_trait_ref))] +#[instrument(level = "debug", skip(tcx, ast_self_ty, ast_trait_ref))] fn check_impl<'tcx>( tcx: TyCtxt<'tcx>, item: &'tcx hir::Item<'tcx>, @@ -1245,13 +1240,13 @@ fn check_impl<'tcx>( ast_trait_ref: &Option<hir::TraitRef<'_>>, constness: hir::Constness, ) { - enter_wf_checking_ctxt(tcx, item.span, item.def_id, |wfcx| { + enter_wf_checking_ctxt(tcx, item.span, item.owner_id.def_id, |wfcx| { match *ast_trait_ref { Some(ref ast_trait_ref) => { // `#[rustc_reservation_impl]` impls are not real impls and // therefore don't need to be WF (the trait's `Self: Trait` predicate // won't hold). - let trait_ref = tcx.impl_trait_ref(item.def_id).unwrap(); + let trait_ref = tcx.impl_trait_ref(item.owner_id).unwrap(); let trait_ref = wfcx.normalize(ast_trait_ref.path.span, None, trait_ref); let trait_pred = ty::TraitPredicate { trait_ref, @@ -1273,19 +1268,21 @@ fn check_impl<'tcx>( wfcx.register_obligations(obligations); } None => { - let self_ty = tcx.type_of(item.def_id); - let self_ty = wfcx.normalize(item.span, None, self_ty); + let self_ty = tcx.type_of(item.owner_id); + let self_ty = wfcx.normalize( + item.span, + Some(WellFormedLoc::Ty(item.hir_id().expect_owner().def_id)), + self_ty, + ); wfcx.register_wf_obligation( ast_self_ty.span, - Some(WellFormedLoc::Ty(item.hir_id().expect_owner())), + Some(WellFormedLoc::Ty(item.hir_id().expect_owner().def_id)), self_ty.into(), ); } } - check_where_clauses(wfcx, item.span, item.def_id); - - impl_implied_bounds(tcx, wfcx.param_env, item.def_id, item.span) + check_where_clauses(wfcx, item.span, item.owner_id.def_id); }); } @@ -1321,7 +1318,11 @@ fn check_where_clauses<'tcx>(wfcx: &WfCheckingCtxt<'_, 'tcx>, span: Span, def_id // parameter includes another (e.g., `<T, U = T>`). In those cases, we can't // be sure if it will error or not as user might always specify the other. if !ty.needs_subst() { - wfcx.register_wf_obligation(tcx.def_span(param.def_id), None, ty.into()); + wfcx.register_wf_obligation( + tcx.def_span(param.def_id), + Some(WellFormedLoc::Ty(param.def_id.expect_local())), + ty.into(), + ); } } } @@ -1426,9 +1427,7 @@ fn check_where_clauses<'tcx>(wfcx: &WfCheckingCtxt<'_, 'tcx>, span: Span, def_id let substituted_pred = predicates.rebind(pred).subst(tcx, substs); // Don't check non-defaulted params, dependent defaults (including lifetimes) // or preds with multiple params. - if substituted_pred.has_param_types_or_consts() - || param_count.params.len() > 1 - || has_region + if substituted_pred.has_non_region_param() || param_count.params.len() > 1 || has_region { None } else if predicates.0.predicates.iter().any(|&(p, _)| p == substituted_pred) { @@ -1465,21 +1464,26 @@ fn check_where_clauses<'tcx>(wfcx: &WfCheckingCtxt<'_, 'tcx>, span: Span, def_id assert_eq!(predicates.predicates.len(), predicates.spans.len()); let wf_obligations = iter::zip(&predicates.predicates, &predicates.spans).flat_map(|(&p, &sp)| { - traits::wf::predicate_obligations(infcx, wfcx.param_env, wfcx.body_id, p, sp) + traits::wf::predicate_obligations( + infcx, + wfcx.param_env.without_const(), + wfcx.body_id, + p, + sp, + ) }); let obligations: Vec<_> = wf_obligations.chain(default_obligations).collect(); wfcx.register_obligations(obligations); } -#[tracing::instrument(level = "debug", skip(wfcx, span, hir_decl))] +#[instrument(level = "debug", skip(wfcx, span, hir_decl))] fn check_fn_or_method<'tcx>( wfcx: &WfCheckingCtxt<'_, 'tcx>, span: Span, sig: ty::PolyFnSig<'tcx>, hir_decl: &hir::FnDecl<'_>, def_id: LocalDefId, - implied_bounds: &mut FxHashSet<Ty<'tcx>>, ) { let tcx = wfcx.tcx(); let sig = tcx.liberate_late_bound_regions(def_id.to_def_id(), sig); @@ -1521,23 +1525,66 @@ fn check_fn_or_method<'tcx>( ); } - implied_bounds.extend(sig.inputs()); - - wfcx.register_wf_obligation(hir_decl.output.span(), None, sig.output().into()); + wfcx.register_wf_obligation( + hir_decl.output.span(), + Some(WellFormedLoc::Param { + function: def_id, + param_idx: sig.inputs().len().try_into().unwrap(), + }), + sig.output().into(), + ); - // FIXME(#27579) return types should not be implied bounds - implied_bounds.insert(sig.output()); + check_where_clauses(wfcx, span, def_id); - debug!(?implied_bounds); + check_return_position_impl_trait_in_trait_bounds( + tcx, + wfcx, + def_id, + sig.output(), + hir_decl.output.span(), + ); +} - check_where_clauses(wfcx, span, def_id); +/// Basically `check_associated_type_bounds`, but separated for now and should be +/// deduplicated when RPITITs get lowered into real associated items. +fn check_return_position_impl_trait_in_trait_bounds<'tcx>( + tcx: TyCtxt<'tcx>, + wfcx: &WfCheckingCtxt<'_, 'tcx>, + fn_def_id: LocalDefId, + fn_output: Ty<'tcx>, + span: Span, +) { + if let Some(assoc_item) = tcx.opt_associated_item(fn_def_id.to_def_id()) + && assoc_item.container == ty::AssocItemContainer::TraitContainer + { + for arg in fn_output.walk() { + if let ty::GenericArgKind::Type(ty) = arg.unpack() + && let ty::Projection(proj) = ty.kind() + && tcx.def_kind(proj.item_def_id) == DefKind::ImplTraitPlaceholder + && tcx.impl_trait_in_trait_parent(proj.item_def_id) == fn_def_id.to_def_id() + { + let bounds = wfcx.tcx().explicit_item_bounds(proj.item_def_id); + let wf_obligations = bounds.iter().flat_map(|&(bound, bound_span)| { + let normalized_bound = wfcx.normalize(span, None, bound); + traits::wf::predicate_obligations( + wfcx.infcx, + wfcx.param_env, + wfcx.body_id, + normalized_bound, + bound_span, + ) + }); + wfcx.register_obligations(wf_obligations); + } + } + } } const HELP_FOR_SELF_TYPE: &str = "consider changing to `self`, `&self`, `&mut self`, `self: Box<Self>`, \ `self: Rc<Self>`, `self: Arc<Self>`, or `self: Pin<P>` (where P is one \ of the previous types except `Self`)"; -#[tracing::instrument(level = "debug", skip(wfcx))] +#[instrument(level = "debug", skip(wfcx))] fn check_method_receiver<'tcx>( wfcx: &WfCheckingCtxt<'_, 'tcx>, fn_sig: &hir::FnSig<'_>, @@ -1629,7 +1676,7 @@ fn receiver_is_valid<'tcx>( // `self: Self` is always valid. if can_eq_self(receiver_ty) { if let Err(err) = wfcx.equate_types(&cause, wfcx.param_env, self_ty, receiver_ty) { - infcx.report_mismatched_types(&cause, self_ty, receiver_ty, err).emit(); + infcx.err_ctxt().report_mismatched_types(&cause, self_ty, receiver_ty, err).emit(); } return true; } @@ -1661,7 +1708,10 @@ fn receiver_is_valid<'tcx>( if let Err(err) = wfcx.equate_types(&cause, wfcx.param_env, self_ty, potential_self_ty) { - infcx.report_mismatched_types(&cause, self_ty, potential_self_ty, err).emit(); + infcx + .err_ctxt() + .report_mismatched_types(&cause, self_ty, potential_self_ty, err) + .emit(); } break; @@ -1728,14 +1778,14 @@ fn check_variances_for_type_defn<'tcx>( item: &hir::Item<'tcx>, hir_generics: &hir::Generics<'_>, ) { - let ty = tcx.type_of(item.def_id); + let ty = tcx.type_of(item.owner_id); if tcx.has_error_field(ty) { return; } - let ty_predicates = tcx.predicates_of(item.def_id); + let ty_predicates = tcx.predicates_of(item.owner_id); assert_eq!(ty_predicates.parent, None); - let variances = tcx.variances_of(item.def_id); + let variances = tcx.variances_of(item.owner_id); let mut constrained_parameters: FxHashSet<_> = variances .iter() @@ -1748,7 +1798,7 @@ fn check_variances_for_type_defn<'tcx>( // Lazily calculated because it is only needed in case of an error. let explicitly_bounded_params = LazyCell::new(|| { - let icx = crate::collect::ItemCtxt::new(tcx, item.def_id.to_def_id()); + let icx = crate::collect::ItemCtxt::new(tcx, item.owner_id.to_def_id()); hir_generics .predicates .iter() @@ -1817,6 +1867,7 @@ fn report_bivariance( impl<'tcx> WfCheckingCtxt<'_, 'tcx> { /// Feature gates RFC 2056 -- trivial bounds, checking for global bounds that /// aren't true. + #[instrument(level = "debug", skip(self))] fn check_false_global_bounds(&mut self) { let tcx = self.ocx.infcx.tcx; let mut span = self.span; @@ -1868,10 +1919,10 @@ impl<'tcx> WfCheckingCtxt<'_, 'tcx> { fn check_mod_type_wf(tcx: TyCtxt<'_>, module: LocalDefId) { let items = tcx.hir_module_items(module); - items.par_items(|item| tcx.ensure().check_well_formed(item.def_id)); - items.par_impl_items(|item| tcx.ensure().check_well_formed(item.def_id)); - items.par_trait_items(|item| tcx.ensure().check_well_formed(item.def_id)); - items.par_foreign_items(|item| tcx.ensure().check_well_formed(item.def_id)); + items.par_items(|item| tcx.ensure().check_well_formed(item.owner_id)); + items.par_impl_items(|item| tcx.ensure().check_well_formed(item.owner_id)); + items.par_trait_items(|item| tcx.ensure().check_well_formed(item.owner_id)); + items.par_foreign_items(|item| tcx.ensure().check_well_formed(item.owner_id)); } /////////////////////////////////////////////////////////////////////////// @@ -1924,40 +1975,6 @@ impl<'a, 'tcx> WfCheckingCtxt<'a, 'tcx> { } } -pub fn impl_implied_bounds<'tcx>( - tcx: TyCtxt<'tcx>, - param_env: ty::ParamEnv<'tcx>, - impl_def_id: LocalDefId, - span: Span, -) -> FxHashSet<Ty<'tcx>> { - // We completely ignore any obligations caused by normalizing the types - // we assume to be well formed. Considering that the user of the implied - // bounds will also normalize them, we leave it to them to emit errors - // which should result in better causes and spans. - tcx.infer_ctxt().enter(|infcx| { - let cause = ObligationCause::misc(span, tcx.hir().local_def_id_to_hir_id(impl_def_id)); - match tcx.impl_trait_ref(impl_def_id) { - Some(trait_ref) => { - // Trait impl: take implied bounds from all types that - // appear in the trait reference. - match infcx.at(&cause, param_env).normalize(trait_ref) { - Ok(Normalized { value, obligations: _ }) => value.substs.types().collect(), - Err(NoSolution) => FxHashSet::default(), - } - } - - None => { - // Inherent impl: take implied bounds from the `self` type. - let self_ty = tcx.type_of(impl_def_id); - match infcx.at(&cause, param_env).normalize(self_ty) { - Ok(Normalized { value, obligations: _ }) => FxHashSet::from_iter([value]), - Err(NoSolution) => FxHashSet::default(), - } - } - } - }) -} - fn error_392( tcx: TyCtxt<'_>, span: Span, |