message: TFTRT: use StrCat and StrAppend in the log
diff: @@ -33,6 +33,7 @@ namespace tensorflow {
  namespace tensorrt {
  namespace segment {
  using ::tensorflow::strings::StrAppend;
  +using ::tensorflow::strings::StrCat;
  // A simple graph representation to mirror tensorflow::Graph. This structure
  // helps saving memory since segmenter modifies the graph in place, preventing
  @@ -433,13 +434,12 @@ tensorflow::Status SegmentGraph(
  }
  node_segments.emplace_back(node);
  }
  - string msg = "There are "
  - + std::to_string(num_unsupported_ops)
  - + " unsupported ops of "
  - + std::to_string(unsupported_ops.size())
  - + " different types in the graph: ";
  + string msg = StrCat("There are ", num_unsupported_ops,
  + " ops of ", unsupported_ops.size(),
  + " different types in the graph that",
  + " are not converted to TensorRT: ");
  for (const auto& elem: unsupported_ops) {
  - msg += elem + ", ";
  + StrAppend(&msg, elem, ", ");
  }
  LOG(INFO) << msg << "(For more information see "
  << "https://docs.nvidia.com/deeplearning"
  