Trouble using IPv6 when no default route is present #405
Description
CI started acting up when Codeberg's Woodpecker stopped having an IPv6 route.
Deeper investigation is pending, but what I think is the trouble and would need to be fixed is that the custom getaddr info variant (that works across platforms even when AI_V6MAPPED is unsupported), and there is no IPv6 loopback address, IPv6 literals are still not let pass through.
Observed behavior on an affected system:
$ ip -6 a 1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 state UNKNOWN qlen 1000 inet6 ::1/128 scope host proto kernel_lo valid_lft forever preferred_lft forever $ ip -6 r $ socat /dev/null tcp6:localhost:1234 || true 2026/02/18 14:15:50 socat[285] W connect(6, AF=10 [0000:0000:0000:0000:0000:0000:0000:0001]:1234, 28): Connection refused 2026/02/18 14:15:50 socat[285] E tcp6:localhost:1234: Connection refused $ echo 'import socket; print(await asyncio.get_event_loop().getaddrinfo("::1", 1234, family=socket.AF_UNSPEC, type=socket.SOCK_DGRAM, proto=socket.IPPROTO_UDP, flags=socket.AI_ADDRCONFIG))' | python3 -m asyncio [...] File "/usr/local/lib/python3.13/socket.py", line 977, in getaddrinfo for res in _socket.getaddrinfo(host, port, family, type, proto, flags): ~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ socket.gaierror: [Errno -9] Address family for hostname not supportedWe're looking up something that is an IP address, so getaddrinfo should never get in our way there.