anchor.diff:        src = ./config-compat.patch;
         inherit configVersion;
       })
  -    (fetchpatch {
  -      name = "glibc-2.25.diff";
  -      url = "https://cgit.freedesktop.org/fontconfig/patch/?id=1ab5258f7c";
  -      sha256 = "0x2a4qx51j3gqcp1kp4lisdzmhrkw1zw0r851d82ksgjlc0vkbaz";
  -    })
     ];
  -  # additionally required for the glibc-2.25 patch; avoid requiring gperf
  -  postPatch = ''
  -    sed s/CHAR_WIDTH/CHARWIDTH/g -i src/fcobjshash.{h,gperf}
  -    sleep 2
  -    touch src/fcobjshash.h
  -  '';
   
     outputs = [ "bin" "dev" "lib" "out" ]; # $out contains all the config
   
     propagatedBuildInputs = [ freetype ];
  -  nativeBuildInputs = [ pkgconfig ];
  +  nativeBuildInputs = [ pkgconfig gperf ];
     buildInputs = [ expat ];
   
     configureFlags = [
  
positive.code:   configVersion = "2.11"; # bump whenever fontconfig breaks compatibility with older configurations
  in
  stdenv.mkDerivation rec {
    name = "fontconfig-2.12.1";
  
    src = fetchurl {
      url = "http://fontconfig.org/release/${name}.tar.bz2";
      sha256 = "1wy7svvp7df6bjpg1m5vizb3ngd7rhb20vpclv3x3qa71khs6jdl";
    };
  
    patches = [
  
negative.code: { stdenv, substituteAll, fetchurl, fetchpatch
  , pkgconfig, freetype, expat, libxslt, gperf, dejavu_fonts
  , hostPlatform
  }:
  
  