IN6_IFF_NODAD
ia->ia6_flags &= ~IN6_IFF_NODAD; /* Mobile IPv6 */
!(ifra->ifra_flags & IN6_IFF_NODAD))
!(ifra->ifra_flags & IN6_IFF_NODAD) &&
ifra.ifra_flags |= IN6_IFF_NODAD;
ia->ia6_flags &= ~IN6_IFF_NODAD;
ifra.ifra_flags |= IN6_IFF_NODAD;