diff --git a/tests/time_test.cpp b/tests/time_test.cpp
index 40e5c6d..f0ad937 100644
--- a/tests/time_test.cpp
+++ b/tests/time_test.cpp
@@ -998,6 +998,10 @@
   ASSERT_EQ(-1, ts.tv_sec);
 }
 
+TEST(time, clock_getres_null_resolution) {
+  ASSERT_EQ(0, clock_getres(CLOCK_REALTIME, nullptr));
+}
+
 TEST(time, clock) {
   // clock(3) is hard to test, but a 1s sleep should cost less than 10ms on average.
   static const clock_t N = 5;