--- /dev/null
+// PR c++/92601
+// { dg-additional-options "-g -fchecking -std=c++17" }
+
+typedef int size_t;
+template <typename, int __v> struct integral_constant {
+ static constexpr int value = __v;
+};
+template <typename> struct A;
+template <typename _Tp> using __remove_cv_t = typename A<_Tp>::type;
+template <typename _Tp, typename _Up>
+struct B : integral_constant<bool, __is_same_as(_Tp, _Up)> {};
+template <typename...> class tuple;
+template <typename> struct A {
+ using type = tuple<const char *, const char *>;
+};
+template <typename> struct C { typedef __remove_cv_t<int> __type; };
+template <typename _Tp> class D {
+public:
+ typedef typename C<_Tp>::__type type;
+};
+template <bool> struct enable_if;
+template <int> struct F {};
+template <typename, typename> class G {
+public:
+ int operator*();
+ void operator++();
+};
+template <typename _Iterator, typename _Container>
+bool operator!=(G<_Iterator, _Container>, G<_Iterator, _Container>);
+template <typename> class H;
+template <typename = H<tuple<const char *, const char *>>> class vector {
+public:
+ typedef G<int, vector> iterator;
+ iterator begin();
+ iterator end();
+};
+template <typename> struct pack_c { typedef pack_c type; };
+template <typename, typename> struct make_index_pack_join;
+template <size_t... Left, size_t... Right>
+struct make_index_pack_join<pack_c<size_t, Left...>, pack_c<size_t, Right...>>
+ : pack_c<size_t> {};
+template <int N>
+struct I
+ : make_index_pack_join<typename I<N / 2>::type, typename I<N / 2>::type> {};
+template <> struct I<1> : pack_c<size_t> {};
+template <typename TTuple, typename>
+struct are_tuples_compatible_not_same
+ : F<B<typename D<TTuple>::type, int>::value> {};
+template <typename...> struct tuple_impl;
+template <size_t... Is, typename... Ts>
+struct tuple_impl<pack_c<size_t, Is...>, Ts...> {
+ template <typename UTuple, typename enable_if<are_tuples_compatible_not_same<
+ tuple<>, UTuple>::value>::type>
+ tuple_impl(UTuple &&);
+};
+template <typename... Ts> class tuple {
+ tuple_impl<typename I<sizeof...(Ts)>::type> _impl;
+ tuple(tuple &) = default;
+};
+vector message_handler_registrations;
+void fn1() {
+ for (auto t : message_handler_registrations)
+ ;
+}