[Bug libstdc++/115885] Build errors when libstdc++ math.h included in extern "C" block

[pinskia at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115885

--- Comment #4 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
(In reply to Eric Gallager from comment #3) 
> Perhaps g++ could issue a warning about it, then?

That is PR 91770.