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

[redi at gcc dot gnu.org]

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

--- Comment #7 from Jonathan Wakely <redi at gcc dot gnu.org> ---
I see. Well please do report to the upstream projects telling them it's bad.