native_code.cpp

   auto TargetTriple = sys::getDefaultTargetTriple();
    Owner->setTargetTriple(TargetTriple);
    std::string Error;
    auto Target = TargetRegistry::lookupTarget(TargetTriple, Error);
    if (!Target) {
        errs() << Error;
        return 1;
    }

    auto CPU = "generic";
    auto Features = "";

    TargetOptions opt;
    auto RM = Optional<Reloc::Model>();
    auto TheTargetMachine =
      Target->createTargetMachine(TargetTriple, CPU, Features, opt, RM);

    Owner->setDataLayout(TheTargetMachine->createDataLayout());

    auto Filename = "output.o";
    std::error_code EC;
    raw_fd_ostream dest(Filename, EC, sys::fs::F_None);
if (EC) {
        errs() << "Could not open file: " << EC.message();
        return 1;
    }

    legacy::PassManager pass;
    auto FileType = TargetMachine::CGFT_ObjectFile;

    if (TheTargetMachine->addPassesToEmitFile(pass, dest, FileType)) {
        errs() << "TheTargetMachine can't emit a file of this type";
       return 1;
    }

    pass.run(*Owner);
    dest.flush();