diff --git a/src/shared/bus-util.h b/src/shared/bus-util.h
index 1b58744d8e..80f4606ba4 100644
--- a/src/shared/bus-util.h
+++ b/src/shared/bus-util.h
@@ -65,7 +65,7 @@ int bus_connect_transport_systemd(BusTransport transport, const char *host, bool
 
 typedef int (*bus_message_print_t) (const char *name, const char *expected_value, sd_bus_message *m, bool value, bool all);
 
-int bus_print_property_value(const char *name, const char *expected_value, bool only_value, const char *fmt, ...);
+int bus_print_property_value(const char *name, const char *expected_value, bool only_value, const char *fmt, ...) _printf_(4,5);
 int bus_message_print_all_properties(sd_bus_message *m, bus_message_print_t func, char **filter, bool value, bool all, Set **found_properties);
 int bus_print_all_properties(sd_bus *bus, const char *dest, const char *path, bus_message_print_t func, char **filter, bool value, bool all, Set **found_properties);