message: adds compile guard
diff: @@ -200,6 +200,9 @@ private:
  };
  +#if GINKGO_BUILD_MPI
  +
  +
  class MpiWrappedTimer : public Timer {
  public:
  MpiWrappedTimer(std::shared_ptr<const gko::Executor> exec,
  @@ -229,4 +232,5 @@ private:
  };
  +#endif // GINKGO_BUILD_MPI
  #endif // GKO_BENCHMARK_UTILS_TIMER_IMPL_HPP_
  