diff -r dc6439c0b8b1 -r b07a0dbc8a38 src/Tools/Code/code_haskell.ML
--- a/src/Tools/Code/code_haskell.ML	Sat Nov 27 14:32:08 2010 +0100
+++ b/src/Tools/Code/code_haskell.ML	Sat Nov 27 15:28:00 2010 +0100
@@ -353,7 +353,7 @@
             val _ = File.check destination;
             val filepath = (Path.append destination o Path.ext "hs" o Path.explode o implode
               o separate "/" o Long_Name.explode) module_name;
-            val _ = File.mkdir_leaf (Path.dir filepath);
+            val _ = Isabelle_System.mkdir_leaf (Path.dir filepath);
           in
             (File.write filepath o format [] width o Pretty.chunks2)
               [str "{-# OPTIONS_GHC -fglasgow-exts #-}", content]