anchor.diff:                              ${if static then "LDFLAGS=-static" else ""}
                               --with${if static == true || popt == null then "" else "out"}-included-popt
                               --with${if avahi != null then "" else "out"}-avahi
  -                            --with${if gtk2 != null then "" else "out"}-gtk
  +                            --with${if gtk3 != null then "" else "out"}-gtk
                               --without-gnome
                               --enable-rfc2553
                               --disable-Werror   # a must on gcc 4.6
  
positive.code: 
  let
    name    = "distcc";
    version = "2016-02-24";
    distcc = stdenv.mkDerivation {
      name = "${name}-${version}";
      src = fetchFromGitHub {
        owner = "distcc";
        repo = "distcc";
        rev = "b2fa4e21b4029e13e2c33f7b03ca43346f2cecb8";
        sha256 = "1vj31wcdas8wy52hy6749mlrca9v6ynycdiigx5ay8pnya9z73c6";
      };
  
    nativeBuildInputs = [ pkg-config ];
      buildInputs = [popt avahi pkg-config python3 gtk2 autoconf automake which procps libiberty_static];
      preConfigure =
      ''
        export CPATH=$(ls -d ${gcc.cc}/lib/gcc/*/${gcc.cc.version}/plugin/include)
  
negative.code: { lib, stdenv, fetchFromGitHub, popt, avahi, pkg-config, python3, gtk3, runCommand
  , gcc, autoconf, automake, which, procps, libiberty_static
  , runtimeShell
  , sysconfDir ? ""   # set this parameter to override the default value $out/etc
  