[PATCH] X86-64: Add _dl_runtime_resolve_avx[512]_opt [BZ #20508]

[H.J. Lu]

On Tue, Oct 4, 2016 at 12:20 PM, Florian Weimer <fweimer@redhat.com> wrote:
> On 10/04/2016 06:08 PM, H.J. Lu wrote:
>>>>>>
>>>>>> Good question.  This is also needed:
>>>>>>
>>>>>> commit f43cb35c9b3c35addc6dc0f1427caf51786ca1d2
>>>>>> Author: H.J. Lu <hjl.tools@gmail.com>
>>>>>> Date:   Fri Jul 1 05:54:43 2016 -0700
>>>>>>
>>>>>>     Require binutils 2.24 to build x86-64 glibc [BZ #20139]
>>>
>>>
>>>
>>>>> That's not really backportable, I'm afraid.  Our users don't expect we
>>>>> break
>>>>> builds in this way.
>>>>>
>>>>
>>>> Who are those users?
>>>
>>>
>>>
>>> We don't know, really.  But moving forward the baseline binutils
>>> requirement
>>> in a stable release really contradicts what a stable release is about.
>
>
>> Do our users expect a broken glibc binary of a stable release on AVX512
>> machine?
>
>
> Either switch to the XSAVE approach, or encode the relevant opcodes using
> .byte.
>
> We used the latter in Red Hat Enterprise Linux 6, and I'm attaching our
> patch in case it is helpful.
>

This patch was for a very different code base.  _dl_runtime_resolve
has been rewritten in glibc 2.23.


-- 
H.J.