libavcodec/h264_direct.c:359: error: Uninitialized Value
  The value read from ref[_] was never initialized.

libavcodec/h264_direct.c:359:21: 
357.                 if (ref[0] > 0)
358.                     a = mv[0];
359.                 if (ref[1] > 0)
                         ^
360.                     b = mv[1];
361.                 n++;
