Bug#870676: ffmpeg requires NEON on armhf, which is not part of the ARMv7 ABI

[Edmund Grimley Evans]

James:

> I think the runtime is working, but this is the testcase from the SIGBUS
> bug which you can use:
>
> ffmpeg -f lavfi -i testsrc=s=32x32:d=0.1 -strict -2 -c:v libx264rgb -f avi libx264rgb.avi -y -hide_banner -nostdin
> ffmpeg -strict -2 -i libx264rgb.avi -t 1 -c:v rawvideo -c:a pcm_s32le -f nut /dev/null -y -hide_banner -nostdin
>
> Since the SIGBUS bug occurs in NEON code, if the runtime detection is
> working, this will _only_ fail on machines with NEON and work on
> non-NEON machines.

This bug was closed while I was sleeping, but I will mention anyway
that with 7:3.3.3-1 those commands give a SIGBUS, as expected, but
only if /proc is mounted.

Presumably with the fixed version, 7:3.3.3-2, performance will be
measurably worse on a system with NEON when /proc is not mounted.

Upstream should probably switch to using getauxval(). Do you want to
suggest it to them?