[Bug c++/109648] New: ICE: tree check: expected type_pack_expansion or expr_pack_expansion, have error_mark in tsubst_pack_expansion, at cp/pt.cc:13551

[hewillk at gmail dot com via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109648

            Bug ID: 109648
           Summary: ICE: tree check: expected type_pack_expansion or
                    expr_pack_expansion, have error_mark in
                    tsubst_pack_expansion, at cp/pt.cc:13551
           Product: gcc
           Version: 13.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: hewillk at gmail dot com
  Target Milestone: ---

struct S {
  int operator[](int);
};

auto foo(auto v) {
  return [&]<int... Is> {
    return (v()[Is] + ...);
  }.template operator()<>();
}

auto test() {
  auto v = [] { return S{}; };
  return [&]<int... Is> {
    return (foo(v()[Is]) + ...);
  }.template operator()<>();
}

int main() {
  test();
}

https://godbolt.org/z/Ye89xfKdY