randconfig build error with next-20141218, in net/netfilter/xt_socket.c

Building with the attached randconfig file,

net/built-in.o: In function `socket_mt_init':
/home/jim/linux/net/netfilter/xt_socket.c:477: undefined reference to
`nf_defrag_ipv6_enable'
make: *** [vmlinux] Error 1

cf. https://lkml.org/lkml/2013/9/5/390, though in this case IPV6=y is
set in the configuration file.