Corrected a bug related to an “unused” macro unintentionally being used in a way not intended; GCC 6.20 compiler picked up on conflict and flagged code as in error (GCC 6.20 is installed by default with the Ubuntu 16.10 release). Lesson learned - macros stink and can be dangerous. Modern C++ compilers in general not only generate errors for C++ code that does not conform to the standard or syntactically make sense, but they also are starting to generate warnings if code quality or clarity of purpose is in question - this is a good thing.