port-i386/51462: mDNSResponder name resolution broken in 7.99.36 i386

[richard%NetBSD.org@localhost]

>Number:         51462
>Category:       port-i386
>Synopsis:       mDNSResponder name resolution broken in 7.99.36 i386
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    port-i386-maintainer
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Wed Sep 07 14:00:00 +0000 2016
>Originator:     Richard PALO
>Release:        NetBSD 7.99.36 (GENERIC)
>Organization:
>Environment:
NetBSD nb32 7.99.36 NetBSD 7.99.36 (GENERIC) #0: Wed Sep  7 00:49:06 CEST 2016  richard%nb32.xxxx.fr@localhost:/usr/obj/sys/arch/i386/compile/GENERIC i386

>Description:
as discussed on current-user@, i386 still has issues resolving mdns hostnames.

>nb32$ grep hosts /etc/nsswitch.conf
>hosts:          files dns mdnsd multicast_dns
># hosts:                dns, files, nis, mdnsd, multicast_dns

I tried:
> # /usr/sbin/mdnsd -debug
> CheckNATMappings: Failed to allocate port 5350 UDP multicast socket for NAT-PMP announcements

in another session:
> nb32$ grep 5350 /etc/services 
> #                  5350        tcp    Reserved
> pcp-multicast      5350/udp    # Port Control Protocol  ...   
> nb32$ ping omnis.local
> ping: Cannot resolve "omnis.local" (Resolver internal error)

where it works okay on a different (linux) client:
> richard@odroid-001e06336dd6:/home/richard$ ping omnis.local
> PING omnis.local (192.168.0.6) 56(84) bytes of data.
> 64 bytes from omnis.local (192.168.0.6): icmp_seq=1 ttl=255 time=0.569 ms
> 64 bytes from omnis.local (192.168.0.6): icmp_seq=2 ttl=255 time=0.659 ms
> ...



>How-To-Repeat:
see above
>Fix: