mdb_conf_isa
.t_isa = (const char *(*)())mdb_conf_isa,
arg_i.a_un.a_str = mdb_conf_isa();
extern const char *mdb_conf_isa(void);
mdb.m_root, mdb_conf_isa());
.t_isa = (const char *(*)())mdb_conf_isa,
.t_isa = (const char *(*)())mdb_conf_isa,
.t_isa = (const char *(*)())mdb_conf_isa,
.t_isa = (const char *(*)())mdb_conf_isa,
.t_isa = (const char *(*)())mdb_conf_isa,