libavcodec/h264.c:1019: error: Uninitialized Value
  The value read from ref[_] was never initialized.

libavcodec/h264.c:1019:21: 
1017.             for(list=0; list<2; list++){
1018.                 if(ref[list] >= 0)
1019.                     pred_motion(h, 0, 4, list, ref[list], &mv[list][0], &mv[list][1]);
                          ^
1020.                 else
1021.                     mv[list][0] = mv[list][1] = 0;
