diff --git a/ghc/compiler/basicTypes/UniqSupply.lhs b/ghc/compiler/basicTypes/UniqSupply.lhs
index 4b8a7564f7c5f6f1ada17f766ff64129de7969ac..ba06f24253eed453d67c1e2b92eea0c7519ecc96 100644
--- a/ghc/compiler/basicTypes/UniqSupply.lhs
+++ b/ghc/compiler/basicTypes/UniqSupply.lhs
@@ -86,7 +86,7 @@ mkSplitUniqSupply (C# c#)
 		return (MkSplitUniqSupply uniq s1 s2)
 	    )
 
-	mk_unique = _ccall_ genSymZh		>>= \ (W# u#) ->
+	mk_unique = _ccall_ genSymzh		>>= \ (W# u#) ->
 		    return (I# (w2i (mask# `or#` u#)))
     in
     mk_supply#