anchor.diff:      substitute preload.sh $out/bin/preload-hardened-malloc --replace "\$dir" $out/lib
       chmod 0555 $out/bin/preload-hardened-malloc
     '';
  +
  +  separateDebugInfo = true;
   
     doInstallCheck = true;
     installCheckPhase = ''
  
positive.code: 
  stdenv.mkDerivation rec {
    name = "graphene-hardened-malloc-${version}";
    version = "190405.003.2019.04.01.19";
  
    src = fetchurl {
      url = "https://github.com/GrapheneOS/hardened_malloc/archive/PQ2A.${version}.tar.gz";
      sha256 = "1qczmajy3q07jd236dmal4iq5xxcsrkyw26gc9r4vs4wj4m42d11";
    };
  
    installPhase = ''
  
negative.code:     make
  
      # these tests don't actually appear to generate overflows currently
      rm read_after_free_small string_overflow eight_byte_overflow_large
  
      for t in `find . -regex ".*/[a-z_]+"` ; do
        echo "Running $t..."
  