anchor.diff:  
     buildInputs = [
       (python3.withPackages (p: with p; [ orderedmultidict ]))
  +    gtest
  +  ];
  +
  +  cmakeFlags = [
  +    "-DUHDM_USE_HOST_GTEST=On"
     ];
   
     doCheck = true;
  
positive.code:     rm -rf $out/lib/uhdm
    '';
  
    prePatch = ''
      substituteInPlace CMakeLists.txt --replace \
      'capnp compile' \
      'capnp compile --src-prefix=''${GENDIR}/..'
    '';
  
    meta = {
      description = "Universal Hardware Data Model";
      homepage = "https://github.com/chipsalliance/UHDM";
  
negative.code: , fetchFromGitHub
  , cmake
  , python3
  , gtest
  , fetchpatch
  }:
  
  stdenv.mkDerivation rec {
    pname = "UHDM";
    version = "1.45";
  
    src = fetchFromGitHub {
      owner = "chipsalliance";
      repo = pname;
      rev = "v${version}";
      hash = "sha256-mxQRmI8yUUrSUYa4kUT9URgfqYvuz3V9e1IGjtiHyhc=";
      fetchSubmodules = true;
    };
  
    # Add ability to use local googletest provided from nix instead of
    # the version from the submodule in third_party/. The third_party/ version
    # is slightly older and does not work with our hydra Darwin builds that needs
    # to set a particular temp directory.
    # This patch allows to choose UHDM_USE_HOST_GTEST=On in the cflags.
    patches = [
      (fetchpatch {
        url = "https://github.com/chipsalliance/UHDM/commit/ad60fdb65a7c49fdc8ee3fffdca791f9364af4f5.patch";
        sha256 = "sha256-IkwnepWWmBychJ0mu+kaddUEc9jkldIRq+GyJkhrO8A=";
        name = "allow-local-gtest.patch";
      })
    ];
  
    nativeBuildInputs = [
      cmake
  