libavcodec/vc1.c:3203: error: Uninitialized Value
  The value read from is_coded[_] was never initialized.

libavcodec/vc1.c:3203:27: 
3201.                             s->dsp.vc1_v_overlap(s->dest[dst_idx] + off, s->linesize >> ((i & 4) >> 2));
3202.                     }
3203.                 } else if(is_coded[i]) {
                                ^
3204.                     status = vc1_decode_p_block(v, s->block[i], i, mquant, ttmb, first_block, s->dest[dst_idx] + off, (i&4)?s->uvlinesize:s->linesize, (i&4) && (s->flags & CODEC_FLAG_GRAY));
3205.                     if(!v->ttmbf && ttmb < 8) ttmb = -1;
