[Bug libstdc++/113099] locale without RTTI uses dynamic_cast before gcc 13.2 or has ODR violation since gcc 13.2

[pdimov at gmail dot com via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113099

--- Comment #10 from Peter Dimov <pdimov at gmail dot com> ---
Maybe the right thing to do is to use dynamic_cast only for virtual inheritance
(either have a trait or check whether static_cast isn't a valid expression),
otherwise static_cast, in both cases (standard and user-defined Facet.)