diff --git a/compiler/rustc_trait_selection/src/solve/mod.rs b/compiler/rustc_trait_selection/src/solve/mod.rs index 2f3111a2414..dac8b3cce80 100644 --- a/compiler/rustc_trait_selection/src/solve/mod.rs +++ b/compiler/rustc_trait_selection/src/solve/mod.rs @@ -22,6 +22,7 @@ use rustc_middle::traits::solve::{ CanonicalResponse, Certainty, ExternalConstraintsData, Goal, GoalSource, IsNormalizesToHack, QueryResult, Response, }; +use rustc_middle::traits::Reveal; use rustc_middle::ty::{self, OpaqueTypeKey, Ty, TyCtxt, UniverseIndex}; use rustc_middle::ty::{ CoercePredicate, RegionOutlivesPredicate, SubtypePredicate, TypeOutlivesPredicate, @@ -317,18 +318,21 @@ impl<'tcx> EvalCtxt<'_, 'tcx> { }; // We do no always define opaque types eagerly to allow non-defining uses in the defining scope. - if let (DefineOpaqueTypes::No, ty::AliasKind::Opaque) = (define_opaque_types, kind) { - if let Some(def_id) = alias.def_id.as_local() { - if self - .unify_existing_opaque_tys( - param_env, - OpaqueTypeKey { def_id, args: alias.args }, - self.next_ty_infer(), - ) - .is_empty() - { - return Some(ty); - } + if let DefineOpaqueTypes::No = define_opaque_types + && let Reveal::UserFacing = param_env.reveal() + && let ty::Opaque = kind + && let Some(def_id) = alias.def_id.as_local() + && self.can_define_opaque_ty(def_id) + { + if self + .unify_existing_opaque_tys( + param_env, + OpaqueTypeKey { def_id, args: alias.args }, + self.next_ty_infer(), + ) + .is_empty() + { + return Some(ty); } }