libavcodec/ac3enc.c:1571: error: Uninitialized Value
  The value read from ch0 was never initialized.

libavcodec/ac3enc.c:1571:13: 
1569.         }
1570.         if (ch == CPL_CH)
1571.             ch = ch0;
                  ^
1572.     }
1573. }
