[Bug libstdc++/99846] [11 regression] std::variant comparison operator error for recursive type

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99846

--- Comment #2 from Jonathan Wakely <redi at gcc dot gnu.org> ---
That's because C++20 <=> comparisons aren't present on the branch. They were
added by g:9e58988061f4175896de11af0caf9bdd48c9b046