diff --git a/src/librustc_infer/infer/canonical/query_response.rs b/src/librustc_infer/infer/canonical/query_response.rs index 77f1c6bf281..966bd997877 100644 --- a/src/librustc_infer/infer/canonical/query_response.rs +++ b/src/librustc_infer/infer/canonical/query_response.rs @@ -12,14 +12,15 @@ use crate::infer::canonical::{ Canonical, CanonicalVarValues, CanonicalizedQueryResponse, Certainty, OriginalQueryValues, QueryOutlivesConstraint, QueryRegionConstraints, QueryResponse, }; +use crate::infer::nll_relate::{NormalizationStrategy, TypeRelating, TypeRelatingDelegate}; use crate::infer::region_constraints::{Constraint, RegionConstraintData}; -use crate::infer::InferCtxtBuilder; -use crate::infer::{InferCtxt, InferOk, InferResult}; +use crate::infer::{InferCtxt, InferCtxtBuilder, InferOk, InferResult, NLLRegionVariableOrigin}; use crate::traits::query::{Fallible, NoSolution}; -use crate::traits::TraitEngine; +use crate::traits::{DomainGoal, TraitEngine}; use crate::traits::{Obligation, ObligationCause, PredicateObligation}; use rustc::arena::ArenaAllocatable; use rustc::ty::fold::TypeFoldable; +use rustc::ty::relate::TypeRelation; use rustc::ty::subst::{GenericArg, GenericArgKind}; use rustc::ty::{self, BoundVar, Ty, TyCtxt}; use rustc_data_structures::captures::Captures; @@ -304,13 +305,31 @@ impl<'cx, 'tcx> InferCtxt<'cx, 'tcx> { } (GenericArgKind::Type(v1), GenericArgKind::Type(v2)) => { - let ok = self.at(cause, param_env).eq(v1, v2)?; - obligations.extend(ok.into_obligations()); + TypeRelating::new( + self, + QueryTypeRelatingDelegate { + infcx: self, + param_env, + cause, + obligations: &mut obligations, + }, + ty::Variance::Invariant, + ) + .relate(&v1, &v2)?; } (GenericArgKind::Const(v1), GenericArgKind::Const(v2)) => { - let ok = self.at(cause, param_env).eq(v1, v2)?; - obligations.extend(ok.into_obligations()); + TypeRelating::new( + self, + QueryTypeRelatingDelegate { + infcx: self, + param_env, + cause, + obligations: &mut obligations, + }, + ty::Variance::Invariant, + ) + .relate(&v1, &v2)?; } _ => { @@ -656,3 +675,55 @@ pub fn make_query_region_constraints<'tcx>( QueryRegionConstraints { outlives, member_constraints: member_constraints.clone() } } + +struct QueryTypeRelatingDelegate<'a, 'tcx> { + infcx: &'a InferCtxt<'a, 'tcx>, + obligations: &'a mut Vec>, + param_env: ty::ParamEnv<'tcx>, + cause: &'a ObligationCause<'tcx>, +} + +impl<'tcx> TypeRelatingDelegate<'tcx> for QueryTypeRelatingDelegate<'_, 'tcx> { + fn create_next_universe(&mut self) -> ty::UniverseIndex { + self.infcx.create_next_universe() + } + + fn next_existential_region_var(&mut self, from_forall: bool) -> ty::Region<'tcx> { + let origin = NLLRegionVariableOrigin::Existential { from_forall }; + self.infcx.next_nll_region_var(origin) + } + + fn next_placeholder_region(&mut self, placeholder: ty::PlaceholderRegion) -> ty::Region<'tcx> { + self.infcx.tcx.mk_region(ty::RePlaceholder(placeholder)) + } + + fn generalize_existential(&mut self, universe: ty::UniverseIndex) -> ty::Region<'tcx> { + self.infcx.next_nll_region_var_in_universe( + NLLRegionVariableOrigin::Existential { from_forall: false }, + universe, + ) + } + + fn push_outlives(&mut self, sup: ty::Region<'tcx>, sub: ty::Region<'tcx>) { + self.obligations.push(Obligation { + cause: self.cause.clone(), + param_env: self.param_env, + predicate: ty::Predicate::RegionOutlives(ty::Binder::dummy(ty::OutlivesPredicate( + sup, sub, + ))), + recursion_depth: 0, + }); + } + + fn push_domain_goal(&mut self, _: DomainGoal<'tcx>) { + bug!("should never be invoked with eager normalization") + } + + fn normalization() -> NormalizationStrategy { + NormalizationStrategy::Eager + } + + fn forbid_inference_vars() -> bool { + true + } +} diff --git a/src/test/ui/nll/user-annotations/type-annotation-with-hrtb.rs b/src/test/ui/nll/user-annotations/type-annotation-with-hrtb.rs new file mode 100644 index 00000000000..1f7c060386b --- /dev/null +++ b/src/test/ui/nll/user-annotations/type-annotation-with-hrtb.rs @@ -0,0 +1,33 @@ +// Regression test for issue #69490 + +// check-pass + +pub trait Trait { + const S: &'static str; +} + +impl Trait<()> for T +where + T: for<'a> Trait<&'a ()>, +{ + // Use of `T::S` here caused an ICE + const S: &'static str = T::S; +} + +// Some similar cases that didn't ICE: + +impl<'a, T> Trait<()> for (T,) +where + T: Trait<&'a ()>, +{ + const S: &'static str = T::S; +} + +impl Trait<()> for [T; 1] +where + T: Trait fn(&'a ())>, +{ + const S: &'static str = T::S; +} + +fn main() {}