https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98150
--- Comment #2 from Nick Krempel <ndkrempel at gmail dot com> --- Realised it doesn't need C++20 and was able to repro back in gcc 6.1 too.
ndkrempel at gmail dot com via Gcc-bugs Fri, 04 Dec 2020 16:51:56 -0800
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98150
--- Comment #2 from Nick Krempel <ndkrempel at gmail dot com> --- Realised it doesn't need C++20 and was able to repro back in gcc 6.1 too.