[Ffmpeg-devel] [BUG] on motion_est.c with cmov

[ramiro at lisha.ufsc.br]

Hello,

Regression tests fail with gcc 4.x (tested with 4.0.4 and 4.1.2) if the
--cpu=i686 option is passed to configure.

This is a regression in gcc, since all works well with gcc 3.4.6. I know
you won't bother working around this in FFmpeg, but I'm at least curious
to know why it happens, since I spent a long time to find it.

I narrowed down the bug to the COPY3_IF_LT macro defined in
libavutil/internal.h. It works alright on all other functions except
sad_hpel_motion_search in motion_est.c.

Attached are the disassemblies for the function with and without HAVE_CMOV.

Ramiro Polla
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