[Bug c++/116491] GCC defines macro linux if -std is not set, and does not define otherwise

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=116491

--- Comment #5 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Specifically https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84400#c2