https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113152
--- Comment #18 from anlauf at gcc dot gnu.org --- (In reply to Steve Kargl from comment #17) > Is there something that is different between your OS and FreeBSD? > Or is there some fundamental difference between C and C++ that > I am unaware of? You should not expect everybody to have the latest MPFR installed. That's the whole point. Please use #if / #else / #endif