Re: dhcpd build break

[Valery Ushakov <uwe%stderr.spb.ru@localhost>]

On Sat, Jun 22, 2013 at 02:32:04 +0100, Roy Marples wrote:

> >/build/netbsd-local/src/external/bsd/dhcpcd/dist/dhcp6.c:641:11:
> >error: operation on 'o->len' may be undefined
> 
> The code in question:
> 
>                         o = D6_NEXT_OPTION(o);
>                         o->code = htons(D6_OPTION_ORO);
>                         o->len = 0;

No, the code in question is:

    o->len = htons(++o->len);

and since on big-endian hton* is a no-op it becomes

    o->len = ++o->len;

which violates C sequence point rules.

-uwe