https://gcc.gnu.org/bugzilla/show_bug.cgi?id=60304
--- Comment #22 from Manuel López-Ibáñez <manu at gcc dot gnu.org> --- (In reply to Jonathan Wakely from comment #21) > (In reply to Manuel López-Ibáñez from comment #19) > > This is exactly what G++'s stdbool.h is doing with -std=gnu++98 and > > -std=c++98. > > <stdbool.h> is a "header" which is C++ standardese for a standard library > header. The rule only applies to user code, not std::lib headers. In your > testcase sys.h is OK but nonsys.h is not. We can drop the nonsys.h case. It is only testing that the no system_headers case also works (according to your other comment, it will be valid if no system_header is included). My point is that the fix cannot be only limited to tweaking stdbool.h, as long as any C++ mode still defines false as a macro.
