libavcodec/vp3.c:737: error: Uninitialized Value
  The value read from motion_x[_] was never initialized.

libavcodec/vp3.c:737:21: 
735.                     s->all_fragments[current_fragment].motion_y = motion_y[k];
736.                 } else {
737.                     s->all_fragments[current_fragment].motion_x = motion_x[0];
                         ^
738.                     s->all_fragments[current_fragment].motion_y = motion_y[0];
739.                 }
