That's assuming you don't include a header that will somewhere have some #if defined(__cpp_rtti) Some ABI- or ODR- breaking code #endif Given how mu

That's assuming you don't include a header that will somewhere have some #if defined(__cpp_rtti) Some ABI- or ODR- breaking code #endif Given how much of these ifdef I can find by grepping on the repos I have cloned on my hard drive, I would in practice really not be too confident about mixing -fno-rtti with -frtti code