nd6_dad_start
nd6_dad_start((struct ifaddr *)ia, delay);
nd6_dad_start(ifa,
nd6_dad_start((struct ifaddr *)ia6, delay);
void nd6_dad_start(struct ifaddr *, int);
nd6_dad_start((struct ifaddr *)ifa, 0);
nd6_dad_start((struct ifaddr *)ifa, 0);