  void connectErr(const AsyncSocketException& ex) noexcept override {
    VLOG(1) << "TCP connect failed: " << ex.what();
    fail(ex);
    delete this;
  }
  void connectErr(const AsyncSocketException& ex) noexcept override {
    VLOG(1) << "TCP connect failed: " << ex.what();
    fail(ex);
    delete this;
  }