anchor.diff:    enableParallelBuilding = true;
   
     postInstall = ''
  -    rm -rf $out/share/gtk-doc
       substituteInPlace "$out/lib/gtk-3.0/3.0.0/printbackends/libprintbackend-cups.la" \
         --replace '-L${gmp.dev}/lib' '-L${gmp.out}/lib'
     '';
  
positive.code: , cupsSupport ? stdenv.isLinux, cups ? null
  }:
  
  assert xineramaSupport -> xlibs.libXinerama != null;
  assert cupsSupport -> cups != null;
  
  let
  
negative.code:     ''; # workaround for bug of nix-mode for Emacs */ '';
    };
  
    meta = with stdenv.lib; {
      description = "A multi-platform toolkit for creating graphical user interfaces";
  
      longDescription = ''
  