1 files changed, 22 insertions, 4 deletions
diff --git a/libcxx/test/std/utilities/time/time.duration/time.duration.arithmetic/op_--int.pass.cpp b/libcxx/test/std/utilities/time/time.duration/time.duration.arithmetic/op_--int.pass.cpp
index 7fc6a1df603..a908c44dda8 100644
--- a/libcxx/test/std/utilities/time/time.duration/time.duration.arithmetic/op_--int.pass.cpp
+++ b/libcxx/test/std/utilities/time/time.duration/time.duration.arithmetic/op_--int.pass.cpp
@@ -11,15 +11,33 @@
 
 // duration
 
-// duration operator--(int);
+// constexpr duration operator--(int);   // constexpr in C++17
 
 #include <chrono>
 #include <cassert>
 
+#include "test_macros.h"
+
+#if TEST_STD_VER > 14
+constexpr bool test_constexpr()
+{
+    std::chrono::hours h1(3);
+    std::chrono::hours h2 = h1--;
+    return h1.count() == 2 && h2.count() == 3;
+}
+#endif
+
+
 int main()
 {
-    std::chrono::hours h(3);
-    std::chrono::hours h2 = h--;
-    assert(h.count() == 2);
+    {
+    std::chrono::hours h1(3);
+    std::chrono::hours h2 = h1--;
+    assert(h1.count() == 2);
     assert(h2.count() == 3);
+    }
+
+#if TEST_STD_VER > 14
+    static_assert(test_constexpr(), "");
+#endif
 }