diff options
Diffstat (limited to 'compiler/rustc_trait_selection')
5 files changed, 117 insertions, 1 deletions
diff --git a/compiler/rustc_trait_selection/src/solve/assembly/mod.rs b/compiler/rustc_trait_selection/src/solve/assembly/mod.rs index 8b5c029428c..68b0db21141 100644 --- a/compiler/rustc_trait_selection/src/solve/assembly/mod.rs +++ b/compiler/rustc_trait_selection/src/solve/assembly/mod.rs @@ -240,6 +240,11 @@ pub(super) trait GoalKind<'tcx>: goal: Goal<'tcx, Self>, ) -> QueryResult<'tcx>; + fn consider_builtin_async_destruct_candidate( + ecx: &mut EvalCtxt<'_, 'tcx>, + goal: Goal<'tcx, Self>, + ) -> QueryResult<'tcx>; + fn consider_builtin_destruct_candidate( ecx: &mut EvalCtxt<'_, 'tcx>, goal: Goal<'tcx, Self>, @@ -520,6 +525,8 @@ impl<'tcx> EvalCtxt<'_, 'tcx> { G::consider_builtin_coroutine_candidate(self, goal) } else if lang_items.discriminant_kind_trait() == Some(trait_def_id) { G::consider_builtin_discriminant_kind_candidate(self, goal) + } else if lang_items.async_destruct_trait() == Some(trait_def_id) { + G::consider_builtin_async_destruct_candidate(self, goal) } else if lang_items.destruct_trait() == Some(trait_def_id) { G::consider_builtin_destruct_candidate(self, goal) } else if lang_items.transmute_trait() == Some(trait_def_id) { diff --git a/compiler/rustc_trait_selection/src/solve/normalizes_to/mod.rs b/compiler/rustc_trait_selection/src/solve/normalizes_to/mod.rs index ebf2a0d9621..6a2e58bc922 100644 --- a/compiler/rustc_trait_selection/src/solve/normalizes_to/mod.rs +++ b/compiler/rustc_trait_selection/src/solve/normalizes_to/mod.rs @@ -814,6 +814,59 @@ impl<'tcx> assembly::GoalKind<'tcx> for NormalizesTo<'tcx> { }) } + fn consider_builtin_async_destruct_candidate( + ecx: &mut EvalCtxt<'_, 'tcx>, + goal: Goal<'tcx, Self>, + ) -> QueryResult<'tcx> { + let self_ty = goal.predicate.self_ty(); + let discriminant_ty = match *self_ty.kind() { + ty::Bool + | ty::Char + | ty::Int(..) + | ty::Uint(..) + | ty::Float(..) + | ty::Array(..) + | ty::RawPtr(..) + | ty::Ref(..) + | ty::FnDef(..) + | ty::FnPtr(..) + | ty::Closure(..) + | ty::CoroutineClosure(..) + | ty::Infer(ty::IntVar(..) | ty::FloatVar(..)) + | ty::Coroutine(..) + | ty::CoroutineWitness(..) + | ty::Pat(..) + | ty::Never + | ty::Adt(_, _) + | ty::Str + | ty::Slice(_) + | ty::Dynamic(_, _, _) + | ty::Tuple(_) + | ty::Error(_) => self_ty.async_destructor_ty(ecx.tcx(), goal.param_env), + + // We do not call `Ty::discriminant_ty` on alias, param, or placeholder + // types, which return `<self_ty as DiscriminantKind>::Discriminant` + // (or ICE in the case of placeholders). Projecting a type to itself + // is never really productive. + ty::Alias(_, _) | ty::Param(_) | ty::Placeholder(..) => { + return Err(NoSolution); + } + + ty::Infer(ty::TyVar(_) | ty::FreshTy(_) | ty::FreshIntTy(_) | ty::FreshFloatTy(_)) + | ty::Foreign(..) + | ty::Bound(..) => bug!( + "unexpected self ty `{:?}` when normalizing `<T as AsyncDestruct>::AsyncDestructor`", + goal.predicate.self_ty() + ), + }; + + ecx.probe_misc_candidate("builtin async destruct").enter(|ecx| { + ecx.eq(goal.param_env, goal.predicate.term, discriminant_ty.into()) + .expect("expected goal term to be fully unconstrained"); + ecx.evaluate_added_goals_and_make_canonical_response(Certainty::Yes) + }) + } + fn consider_builtin_destruct_candidate( _ecx: &mut EvalCtxt<'_, 'tcx>, goal: Goal<'tcx, Self>, diff --git a/compiler/rustc_trait_selection/src/solve/trait_goals.rs b/compiler/rustc_trait_selection/src/solve/trait_goals.rs index e522339358a..ed76ea74f08 100644 --- a/compiler/rustc_trait_selection/src/solve/trait_goals.rs +++ b/compiler/rustc_trait_selection/src/solve/trait_goals.rs @@ -544,6 +544,18 @@ impl<'tcx> assembly::GoalKind<'tcx> for TraitPredicate<'tcx> { ecx.evaluate_added_goals_and_make_canonical_response(Certainty::Yes) } + fn consider_builtin_async_destruct_candidate( + ecx: &mut EvalCtxt<'_, 'tcx>, + goal: Goal<'tcx, Self>, + ) -> QueryResult<'tcx> { + if goal.predicate.polarity != ty::PredicatePolarity::Positive { + return Err(NoSolution); + } + + // `AsyncDestruct` is automatically implemented for every type. + ecx.evaluate_added_goals_and_make_canonical_response(Certainty::Yes) + } + fn consider_builtin_destruct_candidate( ecx: &mut EvalCtxt<'_, 'tcx>, goal: Goal<'tcx, Self>, diff --git a/compiler/rustc_trait_selection/src/traits/project.rs b/compiler/rustc_trait_selection/src/traits/project.rs index 4a8df6c6a5b..9217bf77ba6 100644 --- a/compiler/rustc_trait_selection/src/traits/project.rs +++ b/compiler/rustc_trait_selection/src/traits/project.rs @@ -1074,6 +1074,42 @@ fn assemble_candidates_from_impls<'cx, 'tcx>( | ty::Infer(..) | ty::Error(_) => false, } + } else if lang_items.async_destruct_trait() == Some(trait_ref.def_id) { + match self_ty.kind() { + ty::Bool + | ty::Char + | ty::Int(_) + | ty::Uint(_) + | ty::Float(_) + | ty::Adt(..) + | ty::Str + | ty::Array(..) + | ty::Slice(_) + | ty::RawPtr(..) + | ty::Ref(..) + | ty::FnDef(..) + | ty::FnPtr(..) + | ty::Dynamic(..) + | ty::Closure(..) + | ty::CoroutineClosure(..) + | ty::Coroutine(..) + | ty::CoroutineWitness(..) + | ty::Pat(..) + | ty::Never + | ty::Tuple(..) + | ty::Infer(ty::InferTy::IntVar(_) | ty::InferTy::FloatVar(..)) => true, + + // type parameters, opaques, and unnormalized projections don't have + // a known discriminant and may need to be normalized further or rely + // on param env for async destructor projections + ty::Param(_) + | ty::Foreign(_) + | ty::Alias(..) + | ty::Bound(..) + | ty::Placeholder(..) + | ty::Infer(..) + | ty::Error(_) => false, + } } else if lang_items.pointee_trait() == Some(trait_ref.def_id) { let tail = selcx.tcx().struct_tail_with_normalize( self_ty, @@ -1488,15 +1524,20 @@ fn confirm_builtin_candidate<'cx, 'tcx>( ) -> Progress<'tcx> { let tcx = selcx.tcx(); let self_ty = obligation.predicate.self_ty(); - let args = tcx.mk_args(&[self_ty.into()]); let lang_items = tcx.lang_items(); let item_def_id = obligation.predicate.def_id; let trait_def_id = tcx.trait_of_item(item_def_id).unwrap(); + let args = tcx.mk_args(&[self_ty.into()]); let (term, obligations) = if lang_items.discriminant_kind_trait() == Some(trait_def_id) { let discriminant_def_id = tcx.require_lang_item(LangItem::Discriminant, None); assert_eq!(discriminant_def_id, item_def_id); (self_ty.discriminant_ty(tcx).into(), Vec::new()) + } else if lang_items.async_destruct_trait() == Some(trait_def_id) { + let destructor_def_id = tcx.associated_item_def_ids(trait_def_id)[0]; + assert_eq!(destructor_def_id, item_def_id); + + (self_ty.async_destructor_ty(tcx, obligation.param_env).into(), Vec::new()) } else if lang_items.pointee_trait() == Some(trait_def_id) { let metadata_def_id = tcx.require_lang_item(LangItem::Metadata, None); assert_eq!(metadata_def_id, item_def_id); diff --git a/compiler/rustc_trait_selection/src/traits/select/candidate_assembly.rs b/compiler/rustc_trait_selection/src/traits/select/candidate_assembly.rs index 3ef7cc01f90..61fe66be6f5 100644 --- a/compiler/rustc_trait_selection/src/traits/select/candidate_assembly.rs +++ b/compiler/rustc_trait_selection/src/traits/select/candidate_assembly.rs @@ -81,6 +81,9 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> { } else if lang_items.discriminant_kind_trait() == Some(def_id) { // `DiscriminantKind` is automatically implemented for every type. candidates.vec.push(BuiltinCandidate { has_nested: false }); + } else if lang_items.async_destruct_trait() == Some(def_id) { + // `AsyncDestruct` is automatically implemented for every type. + candidates.vec.push(BuiltinCandidate { has_nested: false }); } else if lang_items.pointee_trait() == Some(def_id) { // `Pointee` is automatically implemented for every type. candidates.vec.push(BuiltinCandidate { has_nested: false }); |