diff options
Diffstat (limited to 'compiler/rustc_trait_selection/src/traits/select/mod.rs')
| -rw-r--r-- | compiler/rustc_trait_selection/src/traits/select/mod.rs | 73 |
1 files changed, 55 insertions, 18 deletions
diff --git a/compiler/rustc_trait_selection/src/traits/select/mod.rs b/compiler/rustc_trait_selection/src/traits/select/mod.rs index 2e65750db25..b46fa9a44d3 100644 --- a/compiler/rustc_trait_selection/src/traits/select/mod.rs +++ b/compiler/rustc_trait_selection/src/traits/select/mod.rs @@ -20,6 +20,7 @@ use rustc_infer::infer::DefineOpaqueTypes; use rustc_infer::infer::at::ToTrace; use rustc_infer::infer::relate::TypeRelation; use rustc_infer::traits::{PredicateObligations, TraitObligation}; +use rustc_macros::{TypeFoldable, TypeVisitable}; use rustc_middle::bug; use rustc_middle::dep_graph::{DepNodeIndex, dep_kinds}; pub use rustc_middle::traits::select::*; @@ -2247,10 +2248,10 @@ impl<'tcx> SelectionContext<'_, 'tcx> { /// Zed<i32> where enum Zed { A(T), B(u32) } -> [i32, u32] /// ``` #[instrument(level = "debug", skip(self), ret)] - fn constituent_types_for_ty( + fn constituent_types_for_auto_trait( &self, t: Ty<'tcx>, - ) -> Result<ty::Binder<'tcx, Vec<Ty<'tcx>>>, SelectionError<'tcx>> { + ) -> Result<ty::Binder<'tcx, AutoImplConstituents<'tcx>>, SelectionError<'tcx>> { Ok(match *t.kind() { ty::Uint(_) | ty::Int(_) @@ -2261,17 +2262,26 @@ impl<'tcx> SelectionContext<'_, 'tcx> { | ty::Error(_) | ty::Infer(ty::IntVar(_) | ty::FloatVar(_)) | ty::Never - | ty::Char => ty::Binder::dummy(Vec::new()), + | ty::Char => { + ty::Binder::dummy(AutoImplConstituents { types: vec![], assumptions: vec![] }) + } // This branch is only for `experimental_default_bounds`. // Other foreign types were rejected earlier in // `assemble_candidates_from_auto_impls`. - ty::Foreign(..) => ty::Binder::dummy(Vec::new()), + ty::Foreign(..) => { + ty::Binder::dummy(AutoImplConstituents { types: vec![], assumptions: vec![] }) + } - ty::UnsafeBinder(ty) => ty.map_bound(|ty| vec![ty]), + ty::UnsafeBinder(ty) => { + ty.map_bound(|ty| AutoImplConstituents { types: vec![ty], assumptions: vec![] }) + } // Treat this like `struct str([u8]);` - ty::Str => ty::Binder::dummy(vec![Ty::new_slice(self.tcx(), self.tcx().types.u8)]), + ty::Str => ty::Binder::dummy(AutoImplConstituents { + types: vec![Ty::new_slice(self.tcx(), self.tcx().types.u8)], + assumptions: vec![], + }), ty::Placeholder(..) | ty::Dynamic(..) @@ -2283,30 +2293,41 @@ impl<'tcx> SelectionContext<'_, 'tcx> { } ty::RawPtr(element_ty, _) | ty::Ref(_, element_ty, _) => { - ty::Binder::dummy(vec![element_ty]) + ty::Binder::dummy(AutoImplConstituents { + types: vec![element_ty], + assumptions: vec![], + }) } - ty::Pat(ty, _) | ty::Array(ty, _) | ty::Slice(ty) => ty::Binder::dummy(vec![ty]), + ty::Pat(ty, _) | ty::Array(ty, _) | ty::Slice(ty) => { + ty::Binder::dummy(AutoImplConstituents { types: vec![ty], assumptions: vec![] }) + } ty::Tuple(tys) => { // (T1, ..., Tn) -- meets any bound that all of T1...Tn meet - ty::Binder::dummy(tys.iter().collect()) + ty::Binder::dummy(AutoImplConstituents { + types: tys.iter().collect(), + assumptions: vec![], + }) } ty::Closure(_, args) => { let ty = self.infcx.shallow_resolve(args.as_closure().tupled_upvars_ty()); - ty::Binder::dummy(vec![ty]) + ty::Binder::dummy(AutoImplConstituents { types: vec![ty], assumptions: vec![] }) } ty::CoroutineClosure(_, args) => { let ty = self.infcx.shallow_resolve(args.as_coroutine_closure().tupled_upvars_ty()); - ty::Binder::dummy(vec![ty]) + ty::Binder::dummy(AutoImplConstituents { types: vec![ty], assumptions: vec![] }) } ty::Coroutine(_, args) => { let ty = self.infcx.shallow_resolve(args.as_coroutine().tupled_upvars_ty()); let witness = args.as_coroutine().witness(); - ty::Binder::dummy([ty].into_iter().chain(iter::once(witness)).collect()) + ty::Binder::dummy(AutoImplConstituents { + types: [ty].into_iter().chain(iter::once(witness)).collect(), + assumptions: vec![], + }) } ty::CoroutineWitness(def_id, args) => self @@ -2314,16 +2335,23 @@ impl<'tcx> SelectionContext<'_, 'tcx> { .tcx .coroutine_hidden_types(def_id) .instantiate(self.infcx.tcx, args) - .map_bound(|witness| witness.types.to_vec()), + .map_bound(|witness| AutoImplConstituents { + types: witness.types.to_vec(), + assumptions: witness.assumptions.to_vec(), + }), // For `PhantomData<T>`, we pass `T`. ty::Adt(def, args) if def.is_phantom_data() => { - ty::Binder::dummy(args.types().collect()) + ty::Binder::dummy(AutoImplConstituents { + types: args.types().collect(), + assumptions: vec![], + }) } - ty::Adt(def, args) => { - ty::Binder::dummy(def.all_fields().map(|f| f.ty(self.tcx(), args)).collect()) - } + ty::Adt(def, args) => ty::Binder::dummy(AutoImplConstituents { + types: def.all_fields().map(|f| f.ty(self.tcx(), args)).collect(), + assumptions: vec![], + }), ty::Alias(ty::Opaque, ty::AliasTy { def_id, args, .. }) => { if self.infcx.can_define_opaque_ty(def_id) { @@ -2333,7 +2361,10 @@ impl<'tcx> SelectionContext<'_, 'tcx> { // which enforces a DAG between the functions requiring // the auto trait bounds in question. match self.tcx().type_of_opaque(def_id) { - Ok(ty) => ty::Binder::dummy(vec![ty.instantiate(self.tcx(), args)]), + Ok(ty) => ty::Binder::dummy(AutoImplConstituents { + types: vec![ty.instantiate(self.tcx(), args)], + assumptions: vec![], + }), Err(_) => { return Err(SelectionError::OpaqueTypeAutoTraitLeakageUnknown(def_id)); } @@ -3113,3 +3144,9 @@ pub(crate) enum ProjectionMatchesProjection { Ambiguous, No, } + +#[derive(Clone, Debug, TypeFoldable, TypeVisitable)] +pub(crate) struct AutoImplConstituents<'tcx> { + pub types: Vec<Ty<'tcx>>, + pub assumptions: Vec<ty::OutlivesPredicate<'tcx, ty::GenericArg<'tcx>>>, +} |