diff options
Diffstat (limited to 'compiler/rustc_infer/src/infer/sub.rs')
| -rw-r--r-- | compiler/rustc_infer/src/infer/sub.rs | 15 |
1 files changed, 12 insertions, 3 deletions
diff --git a/compiler/rustc_infer/src/infer/sub.rs b/compiler/rustc_infer/src/infer/sub.rs index 2c6987cc3..bd38b52ba 100644 --- a/compiler/rustc_infer/src/infer/sub.rs +++ b/compiler/rustc_infer/src/infer/sub.rs @@ -130,12 +130,16 @@ impl<'tcx> TypeRelation<'tcx> for Sub<'_, '_, 'tcx> { Ok(self.tcx().ty_error_with_guaranteed(e)) } - (&ty::Opaque(a_def_id, _), &ty::Opaque(b_def_id, _)) if a_def_id == b_def_id => { + ( + &ty::Alias(ty::Opaque, ty::AliasTy { def_id: a_def_id, .. }), + &ty::Alias(ty::Opaque, ty::AliasTy { def_id: b_def_id, .. }), + ) if a_def_id == b_def_id => { self.fields.infcx.super_combine_tys(self, a, b)?; Ok(a) } - (&ty::Opaque(did, ..), _) | (_, &ty::Opaque(did, ..)) - if self.fields.define_opaque_types && did.is_local() => + (&ty::Alias(ty::Opaque, ty::AliasTy { def_id, .. }), _) + | (_, &ty::Alias(ty::Opaque, ty::AliasTy { def_id, .. })) + if self.fields.define_opaque_types && def_id.is_local() => { self.fields.obligations.extend( infcx @@ -213,6 +217,11 @@ impl<'tcx> TypeRelation<'tcx> for Sub<'_, '_, 'tcx> { where T: Relate<'tcx>, { + // A binder is always a subtype of itself if it's structually equal to itself + if a == b { + return Ok(a); + } + self.fields.higher_ranked_sub(a, b, self.a_is_expected)?; Ok(a) } |