diff --git a/libraries/AP_Common/NMEA.h b/libraries/AP_Common/NMEA.h
index 3207706a68..3054f443cb 100644
--- a/libraries/AP_Common/NMEA.h
+++ b/libraries/AP_Common/NMEA.h
@@ -24,4 +24,4 @@ char *nmea_vaprintf(const char *fmt, va_list ap);
 /*
   formatted print of NMEA message to a uart, with checksum appended
  */
-bool nmea_printf(AP_HAL::UARTDriver *uart, const char *fmt, ...);
+bool nmea_printf(AP_HAL::UARTDriver *uart, const char *fmt, ...) FMT_PRINTF(2,3);