diff --git a/src/udev/udevadm-monitor.c b/src/udev/udevadm-monitor.c
index b5f7f0d512d..c0ef073476b 100644
--- a/src/udev/udevadm-monitor.c
+++ b/src/udev/udevadm-monitor.c
@@ -40,7 +40,7 @@ static void sig_handler(int signum) {
 static void print_device(struct udev_device *device, const char *source, int prop) {
         struct timespec ts;
 
-        clock_gettime(CLOCK_MONOTONIC, &ts);
+        assert_se(clock_gettime(CLOCK_MONOTONIC, &ts) == 0);
         printf("%-6s[%"PRI_TIME".%06ld] %-8s %s (%s)\n",
                source,
                ts.tv_sec, ts.tv_nsec/1000,