libavcodec/vp3.c:738: error: Uninitialized Value
  The value read from motion_y[_] was never initialized.

libavcodec/vp3.c:738:21: 
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.                 }
740.             }
