https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96489
--- Comment #7 from DV Henkel-Wallace <gu...@henkel-wallace.org> --- Thanks. That is clear. BTW FWIW, defining <=> myself and then defining == default does appear to do what I want (i.e. I don't have to use. = default with both operators). I saw that cppreference claims that `== default` will do `<=> < 0` -- though I know that site isn't authoritative, merely close to authorotative. Sorry about reporting a non-bug and thanks for your patience in your response.