[FFmpeg-devel] [PATCH]Only set attribute_align_arg for x86_32

Måns Rullgård mans
Tue Jul 6 11:35:41 CEST 2010


Eli Friedman <eli.friedman at gmail.com> writes:

> 2010/7/3 M?ns Rullg?rd <mans at mansr.com>:
>> Carl Eugen Hoyos <cehoyos at ag.or.at> writes:
>>
>>> M?ns Rullg?rd <mans <at> mansr.com> writes:
>>>
>>>> > ?#ifndef attribute_align_arg
>>>> > -#if (!defined(__ICC) || __ICC > 1110) && AV_GCC_VERSION_AT_LEAST(4,2)
>>>> > +#if ARCH_X86_32 && (!defined(__ICC) || __ICC > 1110) &&
>>> ?AV_GCC_VERSION_AT_LEAST(4,2)
>>>> > ?# ? ?define attribute_align_arg __attribute__((force_align_arg_pointer))
>>>> > ?#else
>>>> > ?# ? ?define attribute_align_arg
>>>>
>>>> The warning is annoying, but it serves a purpose.
>>>
>>> Could you elaborate?
>>
>> An aligned stack is beneficial on any CPU, not only x86.
>
> Sure, but force_align_arg_pointer doesn't mean "align the stack"; it
> means "recover from a misaligned stack",

What is the difference?

> and that is only expected to happen on x86-32.

Said who?  Anyhow, I don't think we actually require an aligned stack
on anything but x86, so I'm OK with the patch.

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



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