Is isSourceFilterSupported still needed on AIX builds?

[Alan Bateman]

On 30/12/2019 22:48, Langer, Christoph wrote:
> Hi Alan,
>
> I checked... Although AIX documentation only refers to IPV6_JOIN_GROUP and IPV6_LEAVE_GROUP, as per: https://www.ibm.com/support/knowledgecenter/en/ssw_ibm_i_71/apis/ssocko.htm we can find this in netinet/in.h in both, AIX 7.1 and AIX 7.2:
>
> #define	IPV6_ADD_MEMBERSHIP	IP_ADD_MEMBERSHIP
> #define	IPV6_JOIN_GROUP		IP_ADD_MEMBERSHIP
> #define	IPV6_DROP_MEMBERSHIP	IP_DROP_MEMBERSHIP
> #define	IPV6_LEAVE_GROUP	IP_DROP_MEMBERSHIP
>
> So, both symbols are defined and to me it seems fine to drop their (conditional) definition from Net.c
>
Thanks for checking. Would you have time to check one more thing? As 
part of JDK-8236410 I want to improve the underlying 
join/drop/block/unblock so that we use the protocol independent 
MCAST_XXXX socket options where possible. I have an initial patch [1] 
that should be good enough to try if you have time. My guess is that 
USE_MCAST_XXXX should be defined on AIX. Also I suspect 
Net.canJoin6WithV4Group should return true. It has historically returned 
false on AIX which means that a DatagramChannel to an IPv6 socket cannot 
join IPv4 multicast groups. The spec allows tolerates this but it will 
become an issue in the future once legacy MulticastSocket is switched to 
use a DatagramChannel.

-Alan

[1] http://cr.openjdk.java.net/~alanb/8236410/webrev/