https://gcc.gnu.org/bugzilla/show_bug.cgi?id=119721
Bug ID: 119721 Summary: tuple<> cannot be compared with array<T, 0> Product: gcc Version: 15.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: libstdc++ Assignee: unassigned at gcc dot gnu.org Reporter: hewillk at gmail dot com Target Milestone: --- The following should be well-formed since C++23. #include <tuple> #include <array> int main() { std::array<int, 0> a; std::tuple<> t; auto eq = (t == a); auto cmp = (t <=> a); } https://godbolt.org/z/T9zME3x6v