diff -r 892f8d00426c -r a5da34455a5c src/Tools/Code/code_haskell.ML
--- a/src/Tools/Code/code_haskell.ML	Thu Jul 01 13:38:17 2010 +0200
+++ b/src/Tools/Code/code_haskell.ML	Thu Jul 01 13:47:27 2010 +0200
@@ -382,7 +382,7 @@
           | _ => (Path.ext "hs" o Path.explode o implode o separate "/"
                 o Long_Name.explode) modlname;
         val pathname = Path.append destination filename;
-        val _ = File.mkdir (Path.dir pathname);
+        val _ = File.mkdir_leaf (Path.dir pathname);
       in File.write pathname
         ("{-# OPTIONS_GHC -fglasgow-exts #-}\n\n"
           ^ code_of_pretty content)