[Bug c++/57588] [C++11][constexpr] static constexpr in class fails to link

[redi at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57588

--- Comment #1 from Jonathan Wakely <redi at gcc dot gnu.org> ---
Isn't this just
http://gcc.gnu.org/wiki/VerboseDiagnostics#missing_static_const_definition ?