anchor.diff:    installPhase = ''
       mkdir "$out"
       make install PREFIX="$out"
  -    cp -v cryptopp.dll "$out/lib/libcryptopp.so"
     '';
   
     doCheck = true;
  -  checkPhase = "make test";
  +  checkPhase = "LD_LIBRARY_PATH=`pwd` make test";
   
     meta = {
       description = "Crypto++, a free C++ class library of cryptographic schemes";
  
positive.code: { fetchurl, stdenv, unzip, libtool }:
  
  stdenv.mkDerivation rec {
    name = "crypto++-5.6.0";
  
    src = fetchurl {
      url = "mirror://sourceforge/cryptopp/cryptopp560.zip";
      sha256 = "1icbk50mr1sqycqbxbqg703m8aamz23ajgl22ychxdahz2sz08mm";
    };
  
    patches = [ ./pic.patch ]
  
negative.code:   '';
  
    cxxflags = if stdenv.isi686 then "-march=i686" else
               if stdenv.isx86_64 then "-march=nocona -fPIC" else
               "";
  
    configurePhase = ''
  