I've only seen wrong use: CS students working on a project in C++, using "and" and "or" as identifiers (which their local MSVC compiler apparently was cool with

I've only seen wrong use: CS students working on a project in C++, using "and" and "or" as identifiers (which their local MSVC compiler apparently was cool with) and then being surprised that the course's testing environment (using gcc) found some errors.