libavcodec/mpegvideo_enc.c:2753: error: Uninitialized Value
  The value read from dc[_] was never initialized.

libavcodec/mpegvideo_enc.c:2753:41: 
2751.                                 if(s->mb_intra && s->dc_val[0]){
2752.                                     for(i=0; i<6; i++){
2753.                                         s->dc_val[0][ s->block_index[i] ]= dc[i];
                                              ^
2754.                                         memcpy(s->ac_val[0][s->block_index[i]], ac[i], sizeof(int16_t)*16);
2755.                                     }
