anchor.diff:  
     buildInputs =
       [ mesa libpulseaudio ]
  -    ++ (if withQt5 then [ qtbase qtquick1 qttools ] else [ qt4 ]);
  +    ++ (if withQt5 then [ qtbase qttools ] else [ qt4 ]);
   
     nativeBuildInputs = [ cmake pkgconfig ] ++ optional withQt5 extra-cmake-modules;
   
  
positive.code: { stdenv, lib, fetchurl, cmake, mesa, pkgconfig, libpulseaudio
  , qt4 ? null, extra-cmake-modules ? null, qtbase ? null, qtquick1 ? null, qttools ? null
  , debug ? false }:
  
  with lib;
  
negative.code: in
  
  assert withQt5 -> qtbase != null;
  assert withQt5 -> qttools != null;
  
  stdenv.mkDerivation rec {
  