gcc complained:

client.c: In function 'init_netmask6':
client.c:181:1: warning: no return statement in function returning
non-void

and Suse' build system complained

I: Program returns random data in a function
E: nfs-utils no-return-in-nonvoid-function client.c:181

when I built without --enable-ipv6

Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Steve Dickson <steved@redhat.com>