In some email I received from Andrew Brown, sie wrote:
> 
> >> This change is so simple why are you fighting it?
> >
> >because it would look like this:
> >
> >struct foo {
> >	struct sockaddr *sa1;
> >	struct sockaddr *sm1;
> >	struct sockaddr *sa2;
> >	struct sockaddr *sm2;
> >	struct in_addr a4_1;
> >	struct in6_addr a6_1;
> >	struct in_addr m4_1;
> >	struct in6_addr m6_1;
> >	struct in_addr a4_2;
> >	struct in6_addr a6_2;
> >	struct in_addr m4_2;
> >	struct in6_addr m6_2;
> >};
> 
> since you wouldn't be mixing ipv4 stuff with ipv6 stuff in the same
> rule (would you?), i'd imagine you could do away with some of the
> grotesqueness by unioning most of this.  no?

yes.