diff options
Diffstat (limited to 'compiler')
| -rw-r--r-- | compiler/rustc_infer/src/infer/opaque_types.rs | 14 |
1 files changed, 14 insertions, 0 deletions
diff --git a/compiler/rustc_infer/src/infer/opaque_types.rs b/compiler/rustc_infer/src/infer/opaque_types.rs index c2ef0b41e27..eab5e5a5fb4 100644 --- a/compiler/rustc_infer/src/infer/opaque_types.rs +++ b/compiler/rustc_infer/src/infer/opaque_types.rs @@ -551,6 +551,20 @@ impl<'a, 'tcx> Instantiator<'a, 'tcx> { let predicate = predicate.subst(tcx, substs); debug!(?predicate); + // Replace all other mentions of the same opaque type with the hidden type, + // as the bounds must hold on the hidden type after all. + let predicate = predicate.fold_with(&mut BottomUpFolder { + tcx, + ty_op: |ty| match *ty.kind() { + ty::Opaque(def_id2, substs2) if def_id == def_id2 && substs == substs2 => { + ty_var + } + _ => ty, + }, + lt_op: |lt| lt, + ct_op: |ct| ct, + }); + // We can't normalize associated types from `rustc_infer`, but we can eagerly register inference variables for them. let predicate = predicate.fold_with(&mut BottomUpFolder { tcx, |