[Bug c++/121945] g++ rejects constructor with unsatisfied constraint

[avi at scylladb dot com via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=121945

--- Comment #1 from Avi Kivity <avi at scylladb dot com> ---
The diagnostic is probably conforming.

https://eel.is/c++draft/class.copy.ctor#5