Please, someone correct me if I'm wrong.
I found a bug of memory leak.
static structure "*cd" of "cue_parser.y" was memory leak, when "cue_parser_string()" was parse error and return NULL.
I think solution code.
/- cue_parser.y -
Cd *cue_parse_file(FILE *fp)
if (0 == yyparse())
cd_delete(cd); <- added this code
P.S. Please excuse my English, it isn't good.