Merge "Disable warnings and errors during include-scanning." into main

      std::unordered_map<std::string, std::string> &abs_paths)

      : abs_paths_(abs_paths) {}

  bool BeginSourceFileAction(clang::CompilerInstance &ci) override {

    // Be more resilient against all warnings/errors, as we want

    // include-scanning to work even on incomplete sources.

    ci.getDiagnostics().setEnableAllWarnings(false);

    ci.getDiagnostics().setSeverityForAll(clang::diag::Flavor::WarningOrError,

                                          clang::diag::Severity::Ignored);

    std::string cwd;

    auto cwd_or_err = ci.getVirtualFileSystem().getCurrentWorkingDirectory();

    if (!cwd_or_err || cwd_or_err.get().empty()) return false;

                        main_file.get()->getBuffer().str());

  std::vector<std::string> argv = cmd.CommandLine;

  // Disable all warnings to be more robust in analysis.

  argv.insert(llvm::find(argv, "--"), {"-Wno-error", "-w"});

  fs = OverlayBuiltinHeaders(argv, std::move(fs));

  llvm::IntrusiveRefCntPtr<clang::FileManager> files(