diff -r 39bd6f7c25c2 -r 62fc16341922 src/Tools/Code/code_haskell.ML
--- a/src/Tools/Code/code_haskell.ML	Wed Jun 30 11:39:10 2010 +0200
+++ b/src/Tools/Code/code_haskell.ML	Wed Jun 30 12:20:45 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)