libavcodec/motionpixels.c:247: error: Uninitialized Value
  The value read from p.v was never initialized.

libavcodec/motionpixels.c:247:17: 
245.             p.y = av_clip_uintp2(p.y, 5);
246.             if ((y & 3) == 0) {
247.                 p.v += mp_gradient(mp, 1, mp_get_vlc(mp, gb));
                     ^
248.                 p.v = av_clip_intp2(p.v, 5);
249.                 p.u += mp_gradient(mp, 2, mp_get_vlc(mp, gb));
