[FFmpeg-cvslog] r16488 - in trunk: configure libavutil/mem.c

[Måns Rullgård]

Michael Niedermayer wrote:
> On Fri, Jan 09, 2009 at 03:35:52AM -0200, ramiro wrote:
>> Michael Niedermayer wrote:
>> > On Thu, Jan 08, 2009 at 07:40:18PM -0200, ramiro wrote:
>> >> Michael Niedermayer wrote:
>> >>> On Thu, Jan 08, 2009 at 09:34:06PM +0100, Vitor Sessak wrote:
>> >>>> ramiro wrote:
>> >>>>> Author: ramiro
>> >>>>> Date: Thu Jan  8 00:36:34 2009
>> >>>>> New Revision: 16488
>> >>>>>
>> >>>>> Log:
>> >>>>> Use posix_memalign() if available.
>> >>>> By looking at FATE, it looks like this change broke H264 decoding on
>> gcc
>> >>>> 2.95.3. See for example
>> >>>> http://fate.multimedia.cx/index.php?test_result=6753660 .
>> >>> as far as i understand it fate didnt build 3 revissions and this one
>> >>> does not look like the most likely cause, 16490 looks more likely
>> >> I couldn't get a hold of gcc 2.95 to test, but this patch should fix it.
>> >
>> > i seriously doubt this patch will fix it. The problem IIRC was that
>> > gcc 2.95 had some problem with alignment somewhere. gcc 2.95 should not
>> > have any problem with sse as such.
>>
>> I finally got gcc 2.95 working. This patch really changes nothing.
>>
>> So, what could be done here?
>> - check gcc version in configure and have sse depend on it
>> or
>> - #if defined(HAVE_SSE) && (!defined(__GNUC__) || __GNUC__ > 2)
>> or
>> - disable HAVE_SSE in some internal header based on __GNUC__
>>
>> I'm slightly more in favor of configure, because then we can keep
>> HAVE_SSE as the only basis to disable building SSE code in the future.
>> This patch only disabled selecting it at run-time. The functions are
>> still being built.
>
> fine though you need approval from the configure maintainers for this

Are there any binutils versions still in use that don't support sse?

> also strictly the correct solution would be to leave HAVE_SSE enabled
> as gcc 2.95 supports it and just disable functions where actual alignment
> problems exists.

Disabling working code out of laziness is unacceptable IMO.

-- 
M?ns Rullg?rd
mans at mansr.com