64-bit time_t on 32-bit powerpc

[Justin Hibbits]

On Fri, Jun 2, 2017 at 11:45 PM, Justin Hibbits <jhibbits at freebsd.org> wrote:
> Calling all powerpc(32) users,
>
> Attached is a patch which changes the size of time_t from 32-bit to 64-bit
> on powerpc.  ARM and MIPS already use 64-bit time_t, the only other holdout
> is i386, which cannot be changed.  I want to get this in soon so there's
> plenty of soak time before 12 is branched.  It works well enough for my
> cases, but I want others to poke, prod, and try to break it.  Especially try
> your favorite ports builds, and make sure things still a) build, and b) work
> as expected.
>
> Almost forgot, too... With powerpc64 users, the compat32 has been updated as
> well, obviously.  So, some testing of that is needed, too.
>
> - Justin

I was just informed I forgot a very crucial part of the patch -- the
update to UPDATING:

20170612:
        The FreeBSD/powerpc platform now uses a 64-bit type for time_t.  This is
        a very major incompatible change, so users of FreeBSD/powerpc must be
        careful when performing source upgrades.  It is best to run 'make
        installworld' from an alternate root system, either a live CD/memory
        stick, or a temporary root partition.  Additionally, all ports must be
        recompiled.

In short: Do _not_ try to reboot to the new kernel with existing
userland.  Boot to an alternate userland and install from there.

Also, shortly after I sent out the patch, I realized I hadn't tested
with TARGET_ARCH=powerpc64, which broke.  I'll send out an updated
patch later tonight.

- Justin