diff --git a/testsuite/tests/polykinds/T7438.stderr b/testsuite/tests/polykinds/T7438.stderr
index 92e01e747971f4ca789db41ab2e0ec7dc980e029..b20233cb40c49a1ba9a0085c4adfbf6d17ec51c4 100644
--- a/testsuite/tests/polykinds/T7438.stderr
+++ b/testsuite/tests/polykinds/T7438.stderr
@@ -4,7 +4,7 @@ T7438.hs:6:14:
       ‘t’ is untouchable
         inside the constraints (t2 ~ t3)
         bound by a pattern with constructor
-                   Nil :: forall (a :: k). Thrist a a,
+                   Nil :: forall (k :: BOX) (a :: k). Thrist a a,
                  in an equation for ‘go’
         at T7438.hs:6:4-6
       ‘t’ is a rigid type variable bound by