https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80370
--- Comment #4 from Vittorio Romeo <vittorio.romeo at outlook dot com> --- Even shorter: template <typename> struct tuple_size { static constexpr int value = 1; }; template <long, typename> struct tuple_element { typedef int type; }; template <typename> struct tuple {}; template <int, typename T> int get(T); int main () { [](auto) { [](tuple<int> b) { auto [c] = b; }; }(0); }