1 files changed, 1 insertions, 0 deletions
diff --git a/Sink.hs b/Sink.hs
index 1368cb6..c258dc5 100644
--- a/Sink.hs
+++ b/Sink.hs
@@ -39,6 +39,7 @@ sinkExp w = \case
     Ifold sht e1 e2 e3 -> Ifold sht (sinkExp w e1) (sinkExp w e2) (sinkExp w e3)
     Index e1 e2 -> Index (sinkExp w e1) (sinkExp w e2)
     Shape e -> Shape (sinkExp w e)
+    Undef t -> Undef t
 
 sinkExp1 :: Exp env a -> Exp (t ': env) a
 sinkExp1 = sinkExp (wSucc wId)