https://gcc.gnu.org/bugzilla/show_bug.cgi?id=87016
--- Comment #8 from Jonathan Wakely <redi at gcc dot gnu.org> --- (In reply to bobogu from comment #7) > All right, I'm sorry then... I just thought that as this is undocumented, it > could lead to producing an unportable code. It could, except that you should get the same behaviour for every correct implementation. Your example doesn't compile with libc++, but that's a bug: https://bugs.llvm.org/show_bug.cgi?id=38638
