https://gcc.gnu.org/bugzilla/show_bug.cgi?id=119545
--- Comment #2 from Jonathan Wakely <redi at gcc dot gnu.org> --- Or like so: --- a/libstdc++-v3/include/std/tuple +++ b/libstdc++-v3/include/std/tuple @@ -2534,7 +2534,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION { return [&]<size_t... _Inds>(index_sequence<_Inds...>) { // Fold == over the tuples until non-equal elements are found. - return ((std::get<_Inds>(__t) == std::get<_Inds>(__u)) && ...); + return (bool(std::get<_Inds>(__t) == std::get<_Inds>(__u)) && ...); }(index_sequence_for<_Tps...>{}); }