libavcodec/flacenc.c:800: error: Uninitialized Value
  The value read from ref[_] was never initialized.

libavcodec/flacenc.c:800:13: 
798.         }
799.         for(i=max_order-1; i>0; i--)
800.             ref[i] = ref[i-1] - ref[i];
                 ^
801.     }
802.     opt_order = max_order;
