[Bug c++/102869] New: Expansion pattern 'std::integer_sequence' contains no parameter packs

[hewillk at gmail dot com via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102869

            Bug ID: 102869
           Summary: Expansion pattern 'std::integer_sequence<long unsigned
                    int, __integer_pack(int)(Is)...>' contains no
                    parameter packs
           Product: gcc
           Version: 12.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: hewillk at gmail dot com
  Target Milestone: ---

[11 Regression]

#include <utility>

template<class...>
struct Tuple {};

template<std::size_t... Is>
using tuple_t = Tuple<std::make_index_sequence<Is>...>;

int main() {
  []<std::size_t... Is>(std::index_sequence<Is...>) {
    tuple_t<Is...> t;
  }(std::make_index_sequence<5>{});
}

https://godbolt.org/z/YKWEs5snW