[FFmpeg-devel] Configure with --cpu=host and Clang

[Reimar Döffinger]

On 26.03.2016, at 13:10, yukari yakumo <yukariin at yandex.ru> wrote:
> Hi everyone!
> I'm Gentoo Linux user and currently I play with Clang as default compiler.
> And currently I tried to build ffmpeg 2.8.6 with Clang 3.9.0 and `-march=native` in C(XX)FLAGS (ffmpeg-2.8.6.ebuild automatically convert this to `--cpu=host` configure flag).
> But I get `--cpu=host not supported with compiler clang` error on configure phase. It's seems like output of clang test compilation different from GCC's output.
> I make a little patch that you can find in attachment to fix this issue. This is very similar to GCC's check_native method.

Is there a need for all that?
It's used for gcc because the gcc developers decided to randomly use -march and -mcpu with no sense or system.
If -march=native always does the right thing for clang, just testing if it is accepted should be enough?