diff options
Diffstat (limited to 'src/compiler/scala/tools/nsc/typechecker/Typers.scala')
| -rw-r--r-- | src/compiler/scala/tools/nsc/typechecker/Typers.scala | 9 |
1 files changed, 7 insertions, 2 deletions
diff --git a/src/compiler/scala/tools/nsc/typechecker/Typers.scala b/src/compiler/scala/tools/nsc/typechecker/Typers.scala index cff3f4f0fa..4fb68fc2a9 100644 --- a/src/compiler/scala/tools/nsc/typechecker/Typers.scala +++ b/src/compiler/scala/tools/nsc/typechecker/Typers.scala @@ -222,8 +222,13 @@ trait Typers extends Modes with Adaptations with Tags { new SubstWildcardMap(tparams).apply(tp) case TypeRef(_, sym, _) if sym.isAliasType => val tp0 = tp.dealias - val tp1 = dropExistential(tp0) - if (tp1 eq tp0) tp else tp1 + if (tp eq tp0) { + debugwarn(s"dropExistential did not progress dealiasing $tp, see SI-7126") + tp + } else { + val tp1 = dropExistential(tp0) + if (tp1 eq tp0) tp else tp1 + } case _ => tp } |