libavcodec/vc1dec.c:1599: error: Uninitialized Value
  The value read from oppfield_predC[_] was never initialized.

libavcodec/vc1dec.c:1599:32: 
1597.             oppfield_pred[0] = mid_pred(oppfield_predA[0], oppfield_predB[0], oppfield_predC[0]);
1598.         if (v->numref)
1599.             oppfield_pred[1] = mid_pred(oppfield_predA[1], oppfield_predB[1], oppfield_predC[1]);
                                     ^
1600.     }
1601. 
