in6_are_prefix_equal
int in6_are_prefix_equal(struct in6_addr *p1, struct in6_addr *p2, int len);
!in6_are_prefix_equal(&ifa6->ia_addr.sin6_addr,
in6_are_prefix_equal(&pr->ndpr_prefix.sin6_addr,
in6_are_prefix_equal(&pr->ndpr_prefix.sin6_addr,
in6_are_prefix_equal(&pr->ndpr_prefix.sin6_addr,