[Bug c++/111504] compare operator not defined for recursive data types on C++20

[xgao at nvidia dot com via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111504

--- Comment #3 from Xiang Gao <xgao at nvidia dot com> ---
Cross posted at: https://github.com/llvm/llvm-project/issues/67056