libavcodec/vc1.c:3206: error: Uninitialized Value
  The value read from pat was never initialized.

libavcodec/vc1.c:3206:40: 
3204.                             top_cbp  = v->cbp[s->mb_x - s->mb_stride] >> (i * 4);
3205.                         }else{
3206.                             left_cbp = (i & 1) ? (pat >> ((i-1)*4)) : (v->cbp[s->mb_x - 1]           >> ((i+1)*4));
                                             ^
3207.                             top_cbp  = (i & 2) ? (pat >> ((i-2)*4)) : (v->cbp[s->mb_x - s->mb_stride] >> ((i+2)*4));
3208.                         }
