src/Tools/cache_io.ML

     val (out2, rc) = bash_output (make_cmd in_path out_path)
     val out1 = the_default [] (try (rev o File.fold_lines cons out_path) [])
   in {output=split_lines out2, redirected_output=out1, return_code=rc} end
 
 fun run make_cmd str =
-  Isabelle_System.with_tmp_file cache_io_prefix (fn in_path =>
-    Isabelle_System.with_tmp_file cache_io_prefix (fn out_path =>
+  Isabelle_System.with_tmp_file cache_io_prefix "" (fn in_path =>
+    Isabelle_System.with_tmp_file cache_io_prefix "" (fn out_path =>
       raw_run make_cmd str in_path out_path))
 
 
 (* cache *)