1 files changed, 88 insertions, 0 deletions
diff --git a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.apply/make_from_tuple.pass.cpp b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.apply/make_from_tuple.pass.cpp
index e3a2114..d737435 100644
--- a/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.apply/make_from_tuple.pass.cpp
+++ b/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.apply/make_from_tuple.pass.cpp
@@ -195,6 +195,94 @@ void test_noexcept() {
     }
 }
 
+namespace LWG3528 {
+template <class T, class Tuple>
+auto test_make_from_tuple(T&&, Tuple&& t) -> decltype(std::make_from_tuple<T>(t), uint8_t()) {
+  return 0;
+}
+template <class T, class Tuple>
+uint32_t test_make_from_tuple(...) {
+  return 0;
+}
+
+template <class T, class Tuple>
+static constexpr bool can_make_from_tuple =
+    std::is_same_v<decltype(test_make_from_tuple<T, Tuple>(T{}, Tuple{})), uint8_t>;
+
+template <class T, class Tuple>
+auto test_make_from_tuple_impl(T&&, Tuple&& t)
+    -> decltype(std::__make_from_tuple_impl<T>(
+                    t, typename std::__make_tuple_indices< std::tuple_size_v<std::remove_reference_t<Tuple>>>::type{}),
+                uint8_t()) {
+  return 0;
+}
+template <class T, class Tuple>
+uint32_t test_make_from_tuple_impl(...) {
+  return 0;
+}
+
+template <class T, class Tuple>
+static constexpr bool can_make_from_tuple_impl =
+    std::is_same_v<decltype(test_make_from_tuple_impl<T, Tuple>(T{}, Tuple{})), uint8_t>;
+
+struct A {
+  int a;
+};
+struct B : public A {};
+
+struct C {
+  C(const B&) {}
+};
+
+enum class D {
+  ONE,
+  TWO,
+};
+
+// Test std::make_from_tuple constraints.
+
+// reinterpret_cast
+static_assert(!can_make_from_tuple<int*, std::tuple<A*>>);
+static_assert(can_make_from_tuple<A*, std::tuple<A*>>);
+
+// const_cast
+static_assert(!can_make_from_tuple<char*, std::tuple<const char*>>);
+static_assert(!can_make_from_tuple<volatile char*, std::tuple<const volatile char*>>);
+static_assert(can_make_from_tuple<volatile char*, std::tuple<volatile char*>>);
+static_assert(can_make_from_tuple<char*, std::tuple<char*>>);
+static_assert(can_make_from_tuple<const char*, std::tuple<char*>>);
+static_assert(can_make_from_tuple<const volatile char*, std::tuple<volatile char*>>);
+
+// static_cast
+static_assert(!can_make_from_tuple<int, std::tuple<D>>);
+static_assert(!can_make_from_tuple<D, std::tuple<int>>);
+static_assert(can_make_from_tuple<long, std::tuple<int>>);
+static_assert(can_make_from_tuple<double, std::tuple<float>>);
+static_assert(can_make_from_tuple<float, std::tuple<double>>);
+
+// Test std::__make_from_tuple_impl constraints.
+
+// reinterpret_cast
+static_assert(!can_make_from_tuple_impl<int*, std::tuple<A*>>);
+static_assert(can_make_from_tuple_impl<A*, std::tuple<A*>>);
+
+// const_cast
+static_assert(!can_make_from_tuple_impl<char*, std::tuple<const char*>>);
+static_assert(!can_make_from_tuple_impl<volatile char*, std::tuple<const volatile char*>>);
+static_assert(can_make_from_tuple_impl<volatile char*, std::tuple<volatile char*>>);
+static_assert(can_make_from_tuple_impl<char*, std::tuple<char*>>);
+static_assert(can_make_from_tuple_impl<const char*, std::tuple<char*>>);
+static_assert(can_make_from_tuple_impl<const volatile char*, std::tuple<volatile char*>>);
+
+// static_cast
+static_assert(!can_make_from_tuple_impl<int, std::tuple<D>>);
+static_assert(!can_make_from_tuple_impl<D, std::tuple<int>>);
+static_assert(can_make_from_tuple_impl<long, std::tuple<int>>);
+static_assert(can_make_from_tuple_impl<double, std::tuple<float>>);
+static_assert(can_make_from_tuple_impl<float, std::tuple<double>>);
+
+} // namespace LWG3528
+
 int main(int, char**)
 {
     test_constexpr_construction();