Yet another OSX RTTI question

Hello, I have viewed many old questions, even some resolved, but I cannot figure out how to enable RTTI on OSX (it works on Windows). I need for an external library (mysql-cpp), which cannot work without it.

On Windows UEBuildConfiguration.bForceEnableExceptions = true; is enough. I’ve added bUseRTTI = true; to no avail.

Any information on the UE build system is greatly appreciated.
Thank you.