libavcodec/mpegvideo.c:646: error: Uninitialized Value
  The value read from yc_size was never initialized.

libavcodec/mpegvideo.c:646:21: 
644.             s->dc_val[1] = s->dc_val_base + y_size + s->mb_stride + 1;
645.             s->dc_val[2] = s->dc_val[1] + c_size;
646.             for(i=0;i<yc_size;i++)
                         ^
647.                 s->dc_val_base[i] = 1024;
648.         }
