2 files changed, 56 insertions, 0 deletions
diff --git a/test/libcxx/utilities/variant/variant.variant/variant.assign/copy.pass.cpp b/test/libcxx/utilities/variant/variant.variant/variant.assign/copy.pass.cpp
index c0084e0b5..3295e5cf5 100644
--- a/test/libcxx/utilities/variant/variant.variant/variant.assign/copy.pass.cpp
+++ b/test/libcxx/utilities/variant/variant.variant/variant.assign/copy.pass.cpp
@@ -10,6 +10,9 @@
 
 // UNSUPPORTED: c++98, c++03, c++11, c++14
 
+// Clang 3.8 doesn't generate constexpr special members correctly.
+// XFAIL: clang-3.8
+
 // <variant>
 
 // template <class ...Types> class variant;
@@ -174,8 +177,32 @@ void test_copy_assignment_different_index() {
   }
 }
 
+template <size_t NewIdx, class ValueType>
+constexpr bool test_constexpr_assign_extension_imp(
+    std::variant<long, void*, int>&& v, ValueType&& new_value)
+{
+  const std::variant<long, void*, int> cp(
+      std::forward<ValueType>(new_value));
+  v = cp;
+  return v.index() == NewIdx &&
+        std::get<NewIdx>(v) == std::get<NewIdx>(cp);
+}
+
+void test_constexpr_copy_assignment_extension() {
+#ifdef _LIBCPP_VERSION
+  using V = std::variant<long, void*, int>;
+  static_assert(std::is_trivially_copyable<V>::value, "");
+  static_assert(std::is_trivially_copy_assignable<V>::value, "");
+  static_assert(test_constexpr_assign_extension_imp<0>(V(42l), 101l), "");
+  static_assert(test_constexpr_assign_extension_imp<0>(V(nullptr), 101l), "");
+  static_assert(test_constexpr_assign_extension_imp<1>(V(42l), nullptr), "");
+  static_assert(test_constexpr_assign_extension_imp<2>(V(42l), 101), "");
+#endif
+}
+
 int main() {
   test_copy_assignment_same_index();
   test_copy_assignment_different_index();
   test_copy_assignment_sfinae();
+  test_constexpr_copy_assignment_extension();
 }
diff --git a/test/libcxx/utilities/variant/variant.variant/variant.assign/move.pass.cpp b/test/libcxx/utilities/variant/variant.variant/variant.assign/move.pass.cpp
index 3c8436d5a..44a9f3b10 100644
--- a/test/libcxx/utilities/variant/variant.variant/variant.assign/move.pass.cpp
+++ b/test/libcxx/utilities/variant/variant.variant/variant.assign/move.pass.cpp
@@ -10,6 +10,9 @@
 
 // UNSUPPORTED: c++98, c++03, c++11, c++14
 
+// Clang 3.8 doesn't generate constexpr special members correctly.
+// XFAIL: clang-3.8
+
 // <variant>
 
 // template <class ...Types> class variant;
@@ -160,8 +163,34 @@ void test_move_assignment_different_index() {
   }
 }
 
+
+template <size_t NewIdx, class ValueType>
+constexpr bool test_constexpr_assign_extension_imp(
+    std::variant<long, void*, int>&& v, ValueType&& new_value)
+{
+  std::variant<long, void*, int> v2(
+      std::forward<ValueType>(new_value));
+  const auto cp = v2;
+  v = std::move(v2);
+  return v.index() == NewIdx &&
+        std::get<NewIdx>(v) == std::get<NewIdx>(cp);
+}
+
+void test_constexpr_move_assignment_extension() {
+#ifdef _LIBCPP_VERSION
+  using V = std::variant<long, void*, int>;
+  static_assert(std::is_trivially_copyable<V>::value, "");
+  static_assert(std::is_trivially_move_assignable<V>::value, "");
+  static_assert(test_constexpr_assign_extension_imp<0>(V(42l), 101l), "");
+  static_assert(test_constexpr_assign_extension_imp<0>(V(nullptr), 101l), "");
+  static_assert(test_constexpr_assign_extension_imp<1>(V(42l), nullptr), "");
+  static_assert(test_constexpr_assign_extension_imp<2>(V(42l), 101), "");
+#endif
+}
+
 int main() {
   test_move_assignment_same_index();
   test_move_assignment_different_index();
   test_move_assignment_sfinae();
+  test_constexpr_move_assignment_extension();
 }