[Bug c++/117294] Concept swallow diagnostics when they're defined in terms of type traits

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=117294

--- Comment #8 from Jonathan Wakely <redi at gcc dot gnu.org> ---
I have a patch for (I believe) all of them ...