[FFmpeg-devel] [PATCH] rv34dsp: Exclude mmx for x86_64 at build time

Hendrik Leppkes h.leppkes at gmail.com
Fri Feb 17 15:10:03 EET 2017

On Fri, Feb 17, 2017 at 11:56 AM, Hugo Beauzée-Luyssen <hugo at beauzee.fr> wrote:
> On Fri, Feb 17, 2017, at 11:50 AM, Carl Eugen Hoyos wrote:
>> 2017-02-17 11:24 GMT+01:00 Hugo Beauzée-Luyssen <hugo at beauzee.fr>:
>> > The function is not defined when building for x86_64
>> But it is declared unconditionally.
>> How can the issue you are trying to fix be reproduced?
>> Why is this the only occurrence?
>> Carl Eugen
> Hi,
> This problem arose while building VLC for Android-x86_64.
> I'm quite convinced there is a similar issue for VP8, but we don't use
> that module in our builds.
> It could be a good idea to conditionally declare the function as well
> indeed.

There is already a condition that will exclude actually using the
function on x86_64, and all our regular builds pass just fine.

Note that FFmpeg currently relies on DCE (Dead Code Eliminiation) to
strip references to unused functions, like in this case, so if your
build system doesn't provide DCE, then FFmpeg build can and will fail.

- Hendrik

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