message: docs: Clang STL symbols
  Document a solution until if/when we add support to detect Clang and set this option
  by default.
diff: @@ -61,6 +61,12 @@ Though Envoy has been run in production compiled with GCC 4.9 extensively, we no
  recommend GCC >= 5 due to known issues with std::string thread safety. Clang >= 4.0 is also known
  to work.
  +## Clang STL debug symbols
  +
  +By default Clang drops some debug symbols that are required for pretty printing to work correctly.
  +More information can be found [here](https://bugs.llvm.org/show_bug.cgi?id=24202). The easy solution
  +is to set ```--copt=-fno-limit-debug-info``` on the CLI or in your bazel.rc file.
  +
  # Testing Envoy with Bazel
  All the Envoy tests can be built and run with:
  