diff options
Diffstat (limited to 'compiler/rustc_trait_selection/src/traits/select/confirmation.rs')
| -rw-r--r-- | compiler/rustc_trait_selection/src/traits/select/confirmation.rs | 135 |
1 files changed, 81 insertions, 54 deletions
diff --git a/compiler/rustc_trait_selection/src/traits/select/confirmation.rs b/compiler/rustc_trait_selection/src/traits/select/confirmation.rs index 4bfa341e3..ce3fc2185 100644 --- a/compiler/rustc_trait_selection/src/traits/select/confirmation.rs +++ b/compiler/rustc_trait_selection/src/traits/select/confirmation.rs @@ -9,7 +9,7 @@ use rustc_ast::Mutability; use rustc_data_structures::stack::ensure_sufficient_stack; use rustc_hir::lang_items::LangItem; -use rustc_infer::infer::LateBoundRegionConversionTime::HigherRankedType; +use rustc_infer::infer::BoundRegionConversionTime::HigherRankedType; use rustc_infer::infer::{DefineOpaqueTypes, InferOk}; use rustc_middle::traits::{BuiltinImplSource, SelectionOutputTypeParameterMismatch}; use rustc_middle::ty::{ @@ -71,7 +71,7 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> { ImplSource::Builtin(BuiltinImplSource::Misc, data) } - ProjectionCandidate(idx, _) => { + ProjectionCandidate(idx) => { let obligations = self.confirm_projection_candidate(obligation, idx)?; ImplSource::Param(obligations) } @@ -98,8 +98,13 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> { ImplSource::Builtin(BuiltinImplSource::Misc, vtable_iterator) } - FnPointerCandidate { is_const } => { - let data = self.confirm_fn_pointer_candidate(obligation, is_const)?; + AsyncIteratorCandidate => { + let vtable_iterator = self.confirm_async_iterator_candidate(obligation)?; + ImplSource::Builtin(BuiltinImplSource::Misc, vtable_iterator) + } + + FnPointerCandidate { fn_host_effect } => { + let data = self.confirm_fn_pointer_candidate(obligation, fn_host_effect)?; ImplSource::Builtin(BuiltinImplSource::Misc, data) } @@ -327,8 +332,9 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> { // care about other regions. Erasing late-bound regions is equivalent // to instantiating the binder with placeholders then erasing those // placeholder regions. - let predicate = - self.tcx().erase_regions(self.tcx().erase_late_bound_regions(obligation.predicate)); + let predicate = self + .tcx() + .erase_regions(self.tcx().instantiate_bound_regions_with_erased(obligation.predicate)); let Some(assume) = rustc_transmute::Assume::from_const( self.infcx.tcx, @@ -393,7 +399,7 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> { obligation.recursion_depth + 1, obligation.param_env, trait_def_id, - &trait_ref.args, + trait_ref.args, obligation.predicate, ); @@ -454,7 +460,7 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> { recursion_depth, param_env, impl_def_id, - &args.value, + args.value, parent_trait_pred, ); @@ -552,7 +558,7 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> { let defs: &ty::Generics = tcx.generics_of(assoc_type); if !defs.params.is_empty() && !tcx.features().generic_associated_types_extended { - tcx.sess.delay_span_bug( + tcx.sess.span_delayed_bug( obligation.cause.span, "GATs in trait object shouldn't have been considered", ); @@ -592,7 +598,7 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> { let kind = ty::BoundRegionKind::BrNamed(param.def_id, param.name); let bound_var = ty::BoundVariableKind::Region(kind); bound_vars.push(bound_var); - ty::Region::new_late_bound( + ty::Region::new_bound( tcx, ty::INNERMOST, ty::BoundRegion { @@ -647,8 +653,7 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> { fn confirm_fn_pointer_candidate( &mut self, obligation: &PolyTraitObligation<'tcx>, - // FIXME(effects) - _is_const: bool, + fn_host_effect: ty::Const<'tcx>, ) -> Result<Vec<PredicateObligation<'tcx>>, SelectionError<'tcx>> { debug!(?obligation, "confirm_fn_pointer_candidate"); @@ -669,6 +674,7 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> { self_ty, sig, util::TupleArgumentsFlag::Yes, + fn_host_effect, ) .map_bound(|(trait_ref, _)| trait_ref); @@ -707,7 +713,7 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> { obligation.recursion_depth, obligation.param_env, trait_def_id, - &args, + args, obligation.predicate, ); @@ -730,7 +736,7 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> { debug!(?obligation, ?coroutine_def_id, ?args, "confirm_coroutine_candidate"); - let coroutine_sig = args.as_coroutine().poly_sig(); + let coroutine_sig = args.as_coroutine().sig(); // NOTE: The self-type is a coroutine type and hence is // in fact unparameterized (or at least does not reference any @@ -741,15 +747,14 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> { .no_bound_vars() .expect("unboxed closure type should not capture bound vars from the predicate"); - let trait_ref = super::util::coroutine_trait_ref_and_outputs( + let (trait_ref, _, _) = super::util::coroutine_trait_ref_and_outputs( self.tcx(), obligation.predicate.def_id(), self_ty, coroutine_sig, - ) - .map_bound(|(trait_ref, ..)| trait_ref); + ); - let nested = self.confirm_poly_trait_refs(obligation, trait_ref)?; + let nested = self.confirm_poly_trait_refs(obligation, ty::Binder::dummy(trait_ref))?; debug!(?trait_ref, ?nested, "coroutine candidate obligations"); Ok(nested) @@ -769,17 +774,16 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> { debug!(?obligation, ?coroutine_def_id, ?args, "confirm_future_candidate"); - let coroutine_sig = args.as_coroutine().poly_sig(); + let coroutine_sig = args.as_coroutine().sig(); - let trait_ref = super::util::future_trait_ref_and_outputs( + let (trait_ref, _) = super::util::future_trait_ref_and_outputs( self.tcx(), obligation.predicate.def_id(), obligation.predicate.no_bound_vars().expect("future has no bound vars").self_ty(), coroutine_sig, - ) - .map_bound(|(trait_ref, ..)| trait_ref); + ); - let nested = self.confirm_poly_trait_refs(obligation, trait_ref)?; + let nested = self.confirm_poly_trait_refs(obligation, ty::Binder::dummy(trait_ref))?; debug!(?trait_ref, ?nested, "future candidate obligations"); Ok(nested) @@ -799,17 +803,45 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> { debug!(?obligation, ?coroutine_def_id, ?args, "confirm_iterator_candidate"); - let gen_sig = args.as_coroutine().poly_sig(); + let gen_sig = args.as_coroutine().sig(); - let trait_ref = super::util::iterator_trait_ref_and_outputs( + let (trait_ref, _) = super::util::iterator_trait_ref_and_outputs( self.tcx(), obligation.predicate.def_id(), obligation.predicate.no_bound_vars().expect("iterator has no bound vars").self_ty(), gen_sig, - ) - .map_bound(|(trait_ref, ..)| trait_ref); + ); - let nested = self.confirm_poly_trait_refs(obligation, trait_ref)?; + let nested = self.confirm_poly_trait_refs(obligation, ty::Binder::dummy(trait_ref))?; + debug!(?trait_ref, ?nested, "iterator candidate obligations"); + + Ok(nested) + } + + fn confirm_async_iterator_candidate( + &mut self, + obligation: &PolyTraitObligation<'tcx>, + ) -> Result<Vec<PredicateObligation<'tcx>>, SelectionError<'tcx>> { + // Okay to skip binder because the args on coroutine types never + // touch bound regions, they just capture the in-scope + // type/region parameters. + let self_ty = self.infcx.shallow_resolve(obligation.self_ty().skip_binder()); + let ty::Coroutine(coroutine_def_id, args, _) = *self_ty.kind() else { + bug!("closure candidate for non-closure {:?}", obligation); + }; + + debug!(?obligation, ?coroutine_def_id, ?args, "confirm_async_iterator_candidate"); + + let gen_sig = args.as_coroutine().sig(); + + let (trait_ref, _) = super::util::async_iterator_trait_ref_and_outputs( + self.tcx(), + obligation.predicate.def_id(), + obligation.predicate.no_bound_vars().expect("iterator has no bound vars").self_ty(), + gen_sig, + ); + + let nested = self.confirm_poly_trait_refs(obligation, ty::Binder::dummy(trait_ref))?; debug!(?trait_ref, ?nested, "iterator candidate obligations"); Ok(nested) @@ -820,11 +852,6 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> { &mut self, obligation: &PolyTraitObligation<'tcx>, ) -> Result<Vec<PredicateObligation<'tcx>>, SelectionError<'tcx>> { - let kind = self - .tcx() - .fn_trait_kind_from_def_id(obligation.predicate.def_id()) - .unwrap_or_else(|| bug!("closure candidate for non-fn trait {:?}", obligation)); - // Okay to skip binder because the args on closure types never // touch bound regions, they just capture the in-scope // type/region parameters. @@ -833,16 +860,12 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> { bug!("closure candidate for non-closure {:?}", obligation); }; - let trait_ref = self.closure_trait_ref_unnormalized(obligation, args); - let mut nested = self.confirm_poly_trait_refs(obligation, trait_ref)?; + let trait_ref = + self.closure_trait_ref_unnormalized(obligation, args, self.tcx().consts.true_); + let nested = self.confirm_poly_trait_refs(obligation, trait_ref)?; debug!(?closure_def_id, ?trait_ref, ?nested, "confirm closure candidate obligations"); - nested.push(obligation.with( - self.tcx(), - ty::Binder::dummy(ty::PredicateKind::ClosureKind(closure_def_id, args, kind)), - )); - Ok(nested) } @@ -920,8 +943,12 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> { let a_ty = self.infcx.shallow_resolve(predicate.self_ty()); let b_ty = self.infcx.shallow_resolve(predicate.trait_ref.args.type_at(1)); - let ty::Dynamic(a_data, a_region, ty::Dyn) = *a_ty.kind() else { bug!() }; - let ty::Dynamic(b_data, b_region, ty::Dyn) = *b_ty.kind() else { bug!() }; + let ty::Dynamic(a_data, a_region, ty::Dyn) = *a_ty.kind() else { + bug!("expected `dyn` type in `confirm_trait_upcasting_unsize_candidate`") + }; + let ty::Dynamic(b_data, b_region, ty::Dyn) = *b_ty.kind() else { + bug!("expected `dyn` type in `confirm_trait_upcasting_unsize_candidate`") + }; let source_principal = a_data.principal().unwrap().with_self_ty(tcx, a_ty); let unnormalized_upcast_principal = @@ -985,7 +1012,7 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> { Ok(match (source.kind(), target.kind()) { // Trait+Kx+'a -> Trait+Ky+'b (auto traits and lifetime subtyping). - (&ty::Dynamic(ref data_a, r_a, dyn_a), &ty::Dynamic(ref data_b, r_b, dyn_b)) + (&ty::Dynamic(data_a, r_a, dyn_a), &ty::Dynamic(data_b, r_b, dyn_b)) if dyn_a == dyn_b => { // See `assemble_candidates_for_unsizing` for more info. @@ -1030,7 +1057,7 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> { } // `T` -> `Trait` - (_, &ty::Dynamic(ref data, r, ty::Dyn)) => { + (_, &ty::Dynamic(data, r, ty::Dyn)) => { let mut object_dids = data.auto_traits().chain(data.principal_def_id()); if let Some(did) = object_dids.find(|did| !tcx.check_is_object_safe(*did)) { return Err(TraitNotObjectSafe(did)); @@ -1184,11 +1211,13 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> { obligation: &PolyTraitObligation<'tcx>, impl_def_id: Option<DefId>, ) -> Result<Vec<PredicateObligation<'tcx>>, SelectionError<'tcx>> { - // `~const Destruct` in a non-const environment is always trivially true, since our type is `Drop` - // FIXME(effects) - if true { - return Ok(vec![]); - } + let Some(host_effect_index) = + self.tcx().generics_of(obligation.predicate.def_id()).host_effect_index + else { + bug!() + }; + let host_effect_param: ty::GenericArg<'tcx> = + obligation.predicate.skip_binder().trait_ref.args.const_at(host_effect_index).into(); let drop_trait = self.tcx().require_lang_item(LangItem::Drop, None); @@ -1277,7 +1306,7 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> { let tcx = self.tcx(); stack.extend(tcx.coroutine_hidden_types(def_id).map(|bty| { let ty = bty.instantiate(tcx, args); - debug_assert!(!ty.has_late_bound_regions()); + debug_assert!(!ty.has_bound_regions()); ty })) } @@ -1285,7 +1314,6 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> { // If we have a projection type, make sure to normalize it so we replace it // with a fresh infer variable ty::Alias(ty::Projection | ty::Inherent, ..) => { - // FIXME(effects) this needs constness let predicate = normalize_with_depth_to( self, obligation.param_env, @@ -1296,7 +1324,7 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> { self.tcx(), LangItem::Destruct, cause.span, - [nested_ty], + [nested_ty.into(), host_effect_param], ), polarity: ty::ImplPolarity::Positive, }), @@ -1316,13 +1344,12 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> { // since it's either not `const Drop` (and we raise an error during selection), // or it's an ADT (and we need to check for a custom impl during selection) _ => { - // FIXME(effects) this needs constness let predicate = self_ty.rebind(ty::TraitPredicate { trait_ref: ty::TraitRef::from_lang_item( self.tcx(), LangItem::Destruct, cause.span, - [nested_ty], + [nested_ty.into(), host_effect_param], ), polarity: ty::ImplPolarity::Positive, }); 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