Syscall param open(filename) points to unaddressable byte(s)

valgrind 调试出现如题所示的错误，原因是存取文件名的空间被释放了

源代码：

        cfg->snteam_cfg->snt.score.nd.wrd_dict_db_fn=cfg->wrd_dict_db_fn；

修改之后：          

	cfg->snteam_cfg->snt.heap = wtk_heap_new(1024);
	cfg->snteam_cfg->snt.score.nd.wrd_dict_db_fn= wtk_heap_dup_str(cfg->snteam_cfg->snt.heap, cfg->wrd_dict_db_fn);