anchor.diff:  , debugVersion ? false
   , enableSharedLibraries ? true
   , darwin
  +, buildPackages
  +, buildPlatform
  +, hostPlatform
   }:
   
   let
  
positive.code: 
    outputs = [ "out" ] ++ stdenv.lib.optional enableSharedLibraries "lib";
  
    buildInputs = [ perl groff cmake libxml2 python libffi ]
      ++ stdenv.lib.optionals stdenv.isDarwin [ libcxxabi ];
  
    propagatedBuildInputs = [ ncurses zlib ];
  
negative.code:     ++ stdenv.lib.optionals (isDarwin) [
      "-DLLVM_ENABLE_LIBCXX=ON"
      "-DCAN_TARGET_i386=false"
    ] ++ stdenv.lib.optionals (buildPlatform != hostPlatform) [
      "-DCMAKE_CROSSCOMPILING=True"
      "-DLLVM_TABLEGEN=${buildPackages.llvmPackages_39.llvm}/bin/llvm-tblgen"
    ];
  
    postBuild = ''
  