[Bug c++/90291] [8/9/10 Regression] Inline namespace erroneously extends another namespace

[nathan at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=90291

--- Comment #5 from Nathan Sidwell <nathan at gcc dot gnu.org> ---
Igor, was this distilled from real code?  what was the intent of such an
organization?