anchor.diff:  in
   
   let
  -  version = "17.2.8";
  +  version = "17.3.3";
     branch  = head (splitString "." version);
     driverLink = "/run/opengl-driver" + optionalString stdenv.isi686 "-32";
   in
  
positive.code:     "--enable-shared-glapi"
      "--enable-sysfs"
      "--enable-llvm-shared-libs"
      "--enable-omx"
      "--enable-va"
      "--disable-opencl"
    ];
  
negative.code:       "ftp://ftp.freedesktop.org/pub/mesa/older-versions/${branch}.x/${version}/mesa-${version}.tar.xz"
        "https://mesa.freedesktop.org/archive/mesa-${version}.tar.xz"
      ];
      sha256 = "16rpm4rwmzd4kdgipa1gw262jqg3346gih0y3bsc3bgn1vgcbfj1";
    };
  
    prePatch = "patchShebangs .";
  