Update.
* iconv/gconv_int.h (gconv_module): Add new element from_regex_mem.
* iconv/gconv_conf.c (module_compare): Make s1 and s2 const.
(detect_conflict): New function.
(add_alias): Call detect_conflict to see whether there is already
a module for the new name.
(add_module): Make sure there is no alias for the new name.
(read_conf_file): Call add_alias with new argument.
(__gconv_read_conf): Don't destroy module tree immediately after
walking it. We need it to test the internal conversions for
conflicts.
* iconv/gconv_db.c (find_derivation): Don't allocate memory for
regular expression. There is now room in the module descriptor.
(free_mem): Don't free memory for regular expression.