libavcodec/vc1.c:673: error: Uninitialized Value
  The value read from mvx[_] was never initialized.

libavcodec/vc1.c:673:9: 
671.         for(i=0; i<3;i++) if(!intra[i]) {t1 = i; break;}
672.         for(i= t1+1; i<4; i++)if(!intra[i]) {t2 = i; break;}
673.         tx = (mvx[t1] + mvx[t2]) / 2;
             ^
674.         ty = (mvy[t1] + mvy[t2]) / 2;
675.     } else {
