diff options
Diffstat (limited to 'compiler/rustc_trait_selection/src')
8 files changed, 103 insertions, 27 deletions
diff --git a/compiler/rustc_trait_selection/src/regions.rs b/compiler/rustc_trait_selection/src/regions.rs index 068e90b00b8..2b33b8ac9f8 100644 --- a/compiler/rustc_trait_selection/src/regions.rs +++ b/compiler/rustc_trait_selection/src/regions.rs @@ -4,7 +4,7 @@ use rustc_infer::infer::{InferCtxt, RegionResolutionError}; use rustc_macros::extension; use rustc_middle::traits::ObligationCause; use rustc_middle::traits::query::NoSolution; -use rustc_middle::ty::{self, Ty}; +use rustc_middle::ty::{self, Ty, elaborate}; use crate::traits::ScrubbedTraitError; use crate::traits::outlives_bounds::InferCtxtExt; @@ -46,6 +46,11 @@ impl<'tcx> OutlivesEnvironment<'tcx> { } } + // FIXME(-Znext-trait-solver): Normalize these. + let higher_ranked_assumptions = infcx.take_registered_region_assumptions(); + let higher_ranked_assumptions = + elaborate::elaborate_outlives_assumptions(infcx.tcx, higher_ranked_assumptions); + // FIXME: This needs to be modified so that we normalize the known type // outlives obligations then elaborate them into their region/type components. // Otherwise, `<W<'a> as Mirror>::Assoc: 'b` will not imply `'a: 'b` even @@ -59,6 +64,7 @@ impl<'tcx> OutlivesEnvironment<'tcx> { assumed_wf_tys, disable_implied_bounds_hack, ), + higher_ranked_assumptions, ) } } diff --git a/compiler/rustc_trait_selection/src/solve/delegate.rs b/compiler/rustc_trait_selection/src/solve/delegate.rs index 1a24254d57f..670589faf9c 100644 --- a/compiler/rustc_trait_selection/src/solve/delegate.rs +++ b/compiler/rustc_trait_selection/src/solve/delegate.rs @@ -212,8 +212,14 @@ impl<'tcx> rustc_next_trait_solver::delegate::SolverDelegate for SolverDelegate< // Cannot use `take_registered_region_obligations` as we may compute the response // inside of a `probe` whenever we have multiple choices inside of the solver. let region_obligations = self.0.inner.borrow().region_obligations().to_owned(); + let region_assumptions = self.0.inner.borrow().region_assumptions().to_owned(); let region_constraints = self.0.with_region_constraints(|region_constraints| { - make_query_region_constraints(self.tcx, region_obligations, region_constraints) + make_query_region_constraints( + self.tcx, + region_obligations, + region_constraints, + region_assumptions, + ) }); let mut seen = FxHashSet::default(); diff --git a/compiler/rustc_trait_selection/src/traits/coherence.rs b/compiler/rustc_trait_selection/src/traits/coherence.rs index ce5a4edeaaa..f50f01a285b 100644 --- a/compiler/rustc_trait_selection/src/traits/coherence.rs +++ b/compiler/rustc_trait_selection/src/traits/coherence.rs @@ -461,6 +461,7 @@ fn impl_intersection_has_negative_obligation( // requirements, when proving the negated where clauses below. drop(equate_obligations); drop(infcx.take_registered_region_obligations()); + drop(infcx.take_registered_region_assumptions()); drop(infcx.take_and_reset_region_constraints()); plug_infer_with_placeholders( diff --git a/compiler/rustc_trait_selection/src/traits/outlives_bounds.rs b/compiler/rustc_trait_selection/src/traits/outlives_bounds.rs index 59d3ac21387..53518038f8d 100644 --- a/compiler/rustc_trait_selection/src/traits/outlives_bounds.rs +++ b/compiler/rustc_trait_selection/src/traits/outlives_bounds.rs @@ -78,7 +78,10 @@ fn implied_outlives_bounds<'a, 'tcx>( bounds.retain(|bound| !bound.has_placeholders()); if !constraints.is_empty() { - let QueryRegionConstraints { outlives } = constraints; + // FIXME(higher_ranked_auto): Should we register assumptions here? + // We otherwise would get spurious errors if normalizing an implied + // outlives bound required proving some higher-ranked coroutine obl. + let QueryRegionConstraints { outlives, assumptions: _ } = constraints; let cause = ObligationCause::misc(span, body_id); for &(predicate, _) in &outlives { infcx.register_outlives_constraint(predicate, &cause); diff --git a/compiler/rustc_trait_selection/src/traits/query/type_op/custom.rs b/compiler/rustc_trait_selection/src/traits/query/type_op/custom.rs index 3b549244431..f027ba1c5cb 100644 --- a/compiler/rustc_trait_selection/src/traits/query/type_op/custom.rs +++ b/compiler/rustc_trait_selection/src/traits/query/type_op/custom.rs @@ -80,6 +80,11 @@ where pre_obligations.is_empty(), "scrape_region_constraints: incoming region obligations = {pre_obligations:#?}", ); + let pre_assumptions = infcx.take_registered_region_assumptions(); + assert!( + pre_assumptions.is_empty(), + "scrape_region_constraints: incoming region assumptions = {pre_assumptions:#?}", + ); let value = infcx.commit_if_ok(|_| { let ocx = ObligationCtxt::new(infcx); @@ -100,11 +105,13 @@ where let value = infcx.resolve_vars_if_possible(value); let region_obligations = infcx.take_registered_region_obligations(); + let region_assumptions = infcx.take_registered_region_assumptions(); let region_constraint_data = infcx.take_and_reset_region_constraints(); let region_constraints = query_response::make_query_region_constraints( infcx.tcx, region_obligations, ®ion_constraint_data, + region_assumptions, ); if region_constraints.is_empty() { diff --git a/compiler/rustc_trait_selection/src/traits/query/type_op/mod.rs b/compiler/rustc_trait_selection/src/traits/query/type_op/mod.rs index 4bdf04311a0..018e9748cf0 100644 --- a/compiler/rustc_trait_selection/src/traits/query/type_op/mod.rs +++ b/compiler/rustc_trait_selection/src/traits/query/type_op/mod.rs @@ -180,8 +180,9 @@ where span, )?; output.error_info = error_info; - if let Some(QueryRegionConstraints { outlives }) = output.constraints { + if let Some(QueryRegionConstraints { outlives, assumptions }) = output.constraints { region_constraints.outlives.extend(outlives.iter().cloned()); + region_constraints.assumptions.extend(assumptions.iter().cloned()); } output.constraints = if region_constraints.is_empty() { None diff --git a/compiler/rustc_trait_selection/src/traits/select/confirmation.rs b/compiler/rustc_trait_selection/src/traits/select/confirmation.rs index ee8cef20279..488094b15ac 100644 --- a/compiler/rustc_trait_selection/src/traits/select/confirmation.rs +++ b/compiler/rustc_trait_selection/src/traits/select/confirmation.rs @@ -411,18 +411,33 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> { obligation.predicate.self_ty().map_bound(|ty| self.infcx.shallow_resolve(ty)); let self_ty = self.infcx.enter_forall_and_leak_universe(self_ty); - let types = self.constituent_types_for_ty(self_ty)?; - let types = self.infcx.enter_forall_and_leak_universe(types); + let constituents = self.constituent_types_for_auto_trait(self_ty)?; + let constituents = self.infcx.enter_forall_and_leak_universe(constituents); let cause = obligation.derived_cause(ObligationCauseCode::BuiltinDerived); - let obligations = self.collect_predicates_for_types( + let mut obligations = self.collect_predicates_for_types( obligation.param_env, - cause, + cause.clone(), obligation.recursion_depth + 1, obligation.predicate.def_id(), - types, + constituents.types, ); + // FIXME(coroutine_clone): We could uplift this into `collect_predicates_for_types` + // and do this for `Copy`/`Clone` too, but that's feature-gated so it doesn't really + // matter yet. + for assumption in constituents.assumptions { + let assumption = normalize_with_depth_to( + self, + obligation.param_env, + cause.clone(), + obligation.recursion_depth + 1, + assumption, + &mut obligations, + ); + self.infcx.register_region_assumption(assumption); + } + Ok(obligations) }) } 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>>>, +} |