libavcodec/mpegvideo_motion.c:477: error: Uninitialized Value
  The value read from ptr[_] was never initialized.

libavcodec/mpegvideo_motion.c:477:13: 
475.     for (i = 0; i < 5; i++) {
476.         if (i && mv[i][0] == mv[MID][0] && mv[i][1] == mv[MID][1]) {
477.             ptr[i] = ptr[MID];
                 ^
478.         } else {
479.             ptr[i] = s->sc.obmc_scratchpad + 8 * (i & 1) +
