anchor.diff:      "--enable-gobject-cast-checks"
       "--enable-glib-asserts"
       (enFlag "orc" (orc != null) null)
  +    "--enable-Bsymbolic"
       # Internal plugins
  -    "--enable-static-plugins"
  +    "--disable-static-plugins"
       "--enable-asfdemux"
       "--enable-dvdlpcmdec"
       "--enable-dvdsub"
  
positive.code:     libdvdread
      libmad
      libmpeg2
      orc
      x264
    ];
  
negative.code: , libdvdread
  , libmad
  , libmpeg2
  , mpg123
  , orc
  , x264
  }:
  