libavcodec/vc1dec.c:1582: error: Uninitialized Value
  The value read from oppfield_predC[_] was never initialized.

libavcodec/vc1dec.c:1582:9: 
1580.         samefield_pred[1] = samefield_predC[1];
1581.         oppfield_pred[0] = oppfield_predC[0];
1582.         oppfield_pred[1] = oppfield_predC[1];
              ^
1583.     } else if (b_valid) {
1584.         samefield_pred[0] = samefield_predB[0];
