libavcodec/vc1dec.c:742: error: Uninitialized Value
  The value read from ty was never initialized.

libavcodec/vc1dec.c:742:9: 
740.         }
741.         s->current_picture.f.motion_val[1][s->block_index[0] + v->blocks_off][0] = tx;
742.         s->current_picture.f.motion_val[1][s->block_index[0] + v->blocks_off][1] = ty;
             ^
743.         for (k = 0; k < 4; k++)
744.             v->mv_f[1][s->block_index[k] + v->blocks_off] = f;
