anchor.diff:  
     nativeBuildInputs = [ cmake ];
   
  +  buildInputs = [ gtest ];
  +
     propagatedBuildInputs = [ gflags ];
   
     cmakeFlags = [
  
positive.code: { stdenv, lib, fetchFromGitHub, cmake, gflags, perl }:
  
  stdenv.mkDerivation rec {
    pname = "glog";
  
negative.code:   enableParallelChecking = false;
    checkInputs = [ perl ];
  
    GTEST_FILTER =
      let
        filteredTests = lib.optionals stdenv.hostPlatform.isMusl [
          "Symbolize.SymbolizeStackConsumption"
          "Symbolize.SymbolizeWithDemanglingStackConsumption"
        ] ++ lib.optionals stdenv.hostPlatform.isStatic [
          "LogBacktraceAt.DoesBacktraceAtRightLineWhenEnabled"
        ];
      in
      lib.optionalString doCheck "-${builtins.concatStringsSep ":" filteredTests}";
  
    meta = with lib; {
      homepage = "https://github.com/google/glog";
      license = licenses.bsd3;
  