PATCH: enhance genautomata error message (obvious)

[Ben Elliston]

Our build system ran low on disk space and I then spent more minutes
than I am willing to disclose :-) trying to work out what genattrtab was
complaining about.  I think this is sufficiently obvious, so I've
committed it.

Cheers, Ben

2007-01-18  Ben Elliston  <bje@au.ibm.com>

        * genautomata.c (write_automata): Include xstrerror output in the
        error message if writing the DFA description file fails.

Index: genautomata.c
===================================================================
--- genautomata.c       (revision 120883)
+++ genautomata.c       (working copy)
@@ -9234,8 +9234,8 @@ write_automata (void)
     {
       fflush (output_description_file);
       if (ferror (stdout) != 0)
-       fatal ("Error in writing DFA description file %s",
-               output_description_file_name);
+       fatal ("Error in writing DFA description file %s: %s",
+               output_description_file_name, xstrerror (errno));
       fclose (output_description_file);
     }
   finish_automaton_decl_table ();