1 files changed, 2 insertions, 0 deletions
diff --git a/testsuite/tests/typecheck/should_compile/T6018.hs b/testsuite/tests/typecheck/should_compile/T6018.hs
index 8605cec1a7..99b99d9294 100644
--- a/testsuite/tests/typecheck/should_compile/T6018.hs
+++ b/testsuite/tests/typecheck/should_compile/T6018.hs
@@ -5,6 +5,7 @@
 {-# LANGUAGE UndecidableInstances      #-}
 {-# LANGUAGE ScopedTypeVariables       #-}
 {-# LANGUAGE NoMonomorphismRestriction #-}
+{-# LANGUAGE StandaloneKindSignatures    #-}
 
 module T6018 where
 
@@ -199,6 +200,7 @@ class Kcl a b where
 
 -- Declaring kind injectivity. Here we only claim that knowing the RHS
 -- determines the LHS kind but not the type.
+type L :: k1 -> k2
 type family L (a :: k1) = (r :: k2) | r -> k1 where
     L 'True  = Int
     L 'False = Int