[Bug c++/99931] Unnamed `struct` defined with `using` having internal linkage instead of external, unlike `typedef`, yielding different semantics for two

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99931

--- Comment #6 from Nathaniel Shead <nshead at gcc dot gnu.org> ---
FWIW this issue is CWG2973:
https://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#2973.