anchor.diff:    };
   
     buildInputs = [ gmp readline openssl libjpeg unixODBC libXinerama
  -    libXft libXpm libSM libXt zlib freetype pkgconfig fontconfig ];
  +    libXft libXpm libSM libXt zlib freetype pkgconfig fontconfig ]
  +  ++ stdenv.lib.optional stdenv.isDarwin makeWrapper;
   
     hardeningDisable = [ "format" ];
   
  
positive.code: 
    buildFlags = "world";
  
    meta = {
      homepage = http://www.swi-prolog.org/;
      description = "A Prolog compiler and interpreter";
      license = "LGPL";
  
      platforms = stdenv.lib.platforms.linux;
      maintainers = [ stdenv.lib.maintainers.peti ];
    };
  }
  
negative.code: { stdenv, fetchurl, gmp, readline, openssl, libjpeg, unixODBC, zlib
  , libXinerama, libXft, libXpm, libSM, libXt, freetype, pkgconfig
  , fontconfig, makeWrapper ? stdenv.isDarwin
  }:
  
  let
  