[Bug c++/107571] Missing fallthrough attribute diagnostics

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107571

--- Comment #1 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Apparently this is
https://www.open-std.org/jtc1/sc22/wg21/docs/cwg_defects.html#2406
which we probably never implemented.