[Bug c++/127887] [miscompilation] GCC fails to match a friend declaration with its definition when the return type is `C<> auto` with a defaulted concept argument; friendship and access are lost

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=127887

--- Comment #1 from Drea Pinski <pinskia at gcc dot gnu.org> ---
Concepts part i thought should not take inot account friendship at all. But I
could be wrong.