message: In file made the variable readonly.
diff: @@ -31,7 +31,7 @@ namespace {
  template <typename Scalar>
  bool AreAllBufferElementsEqualTo(const std::vector<Scalar>& buffer_data,
  Scalar value) {
  - for (auto x : buffer_data) {
  + for (const auto& x : buffer_data) {
  if (x != value) {
  return false;
  }
  