https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84890
--- Comment #6 from Jonathan Wakely <redi at gcc dot gnu.org> --- I have very little sympathy for anybody who thinks that an automated message from a compiler is "kind of personal", but how about instead of asking a question or equivocating with "you may want to ..." just say what the required header is: #include <foo.h> to define std::foo
