[PATCH][BZ #18740] Fix for SSE vector math tests run on non SSE4.1 machines

[Carlos O'Donell]

On 07/30/2015 10:42 AM, H.J. Lu wrote:
> On Thu, Jul 30, 2015 at 7:27 AM, Andrew Senkevich
> <andrew.n.senkevich@gmail.com> wrote:
>> Hi,
>>
>> we can build SSE vector math tests with -msse2 because ifunc in vector
>> function itself selects SSE2 or SSE4 implementation to test.
>>
>> 2015-07-30  Andrew Senkevich  <andrew.senkevich@intel.com>
>>
>>         [BZ #18740]
>>         * sysdeps/x86_64/fpu/Makefile (double-vlen2-arch-ext-cflags,
>>         float-vlen4-arch-ext-cflags): Use -msee2 instead of -msse4.
>>
>> diff --git a/ChangeLog b/ChangeLog
>> index bcb14cf..b5c21b5 100644
>> --- a/ChangeLog
>> +++ b/ChangeLog
>> @@ -1,3 +1,9 @@
>> +2015-07-30  Andrew Senkevich  <andrew.senkevich@intel.com>
>> +
>> +       [BZ #18740]
>> +       * sysdeps/x86_64/fpu/Makefile (double-vlen2-arch-ext-cflags,
>> +       float-vlen4-arch-ext-cflags): Use -msee2 instead of -msse4.
>> +
>>  2015-07-30  Mike Frysinger  <vapier@gentoo.org>
>>
>>         * sysdeps/hppa/nptl/bits/pthreadtypes.h (pthread_mutex_t): Change
>> diff --git a/sysdeps/x86_64/fpu/Makefile b/sysdeps/x86_64/fpu/Makefile
>> index e270b8a..28802dd 100644
>> --- a/sysdeps/x86_64/fpu/Makefile
>> +++ b/sysdeps/x86_64/fpu/Makefile
>> @@ -33,12 +33,12 @@ ifeq (yes,$(config-cflags-avx512))
>>  libmvec-tests += double-vlen8 float-vlen16
>>  endif
>>
>> -double-vlen2-arch-ext-cflags = -msse4
>> +double-vlen2-arch-ext-cflags = -msse2
>>  double-vlen4-arch-ext-cflags = -mavx
>>  double-vlen4-arch-ext2-cflags = -mavx2
>>  double-vlen8-arch-ext-cflags = -mavx512f
>>
>> -float-vlen4-arch-ext-cflags = -msse4
>> +float-vlen4-arch-ext-cflags = -msse2
>>  float-vlen8-arch-ext-cflags = -mavx
>>  float-vlen8-arch-ext2-cflags = -mavx2
>>  float-vlen16-arch-ext-cflags = -mavx512f
>>
> 
> SSE2 is the default for x86-64.  Please just remove the line.

Is it the default for all versions we support building glibc with?

What harm is there in leaving the line there for the sake or robustness?

Cheers,
Carlos.