Re: Build failure 'wmmintrin.h' file not found

On Wed, Jan 18, 2017 at 1:21 PM, Dimitry Andric <dim_at_freebsd.org> wrote:
> On 18 Jan 2017, at 14:42, Magnus Ringman <bmr_at_ringman.ch> wrote:
>>
>> On Wed, Jan 18, 2017 at 2:16 PM, Hans Petter Selasky <hps_at_selasky.org>
>> wrote:
> ...
>>> And the error popped out. I'm not observing this error when building a
>>> 12-current kernel from an 11-stable install.
>>
>>
>> Isn't it all bets are off if going to -current from anything but most
>> recent -stable?

Nope. There's a range of supported major branches. This has been the
case for at least 15 years. Typically, we've supported 2-4 old
branches building current due to the needs of the FreeBSD community
and that community making sure it works often enough that we don't
just shut the door to it entirely. Each individual developer only
needs to test the latest branch, but that's not the same as what's
supported. From time to time we bump the minimum system, but it isn't
in lock step with the major branches.

>> Recommended practice[citation needed] would be
>> 10-stable->11-stable->12-current.
>
> That is the safest way, indeed.  But it should not be totally impossible
> to build recent versions of -current on 10.x.

We support building world on 10.3 and newer for -current today. There
were compiler changes to fix bad code generation between 10.2 and
10.3, however, so the usual "any stable-10' is no longer the case. In
fact, it's still supported building from the tip of stable/9 for
current. However, the same compiler bug is not fixed in the last 9.x
release, so there the upgrade is needed.

> Normally, buildworld takes care of the heavy lifting by building all the
> needed tools first.  But if you build only parts of the tree, you might
> encounter "interesting" situations. :)

Anything less than buildworld is defintely not supported when the host
system isn't completely up to date. Well, make kernel-toolchain is
sufficient for make buildkernel.

Warner