diff --git a/newlib/libc/include/time.h b/newlib/libc/include/time.h
index 58c5066ed..e972bd416 100644
--- a/newlib/libc/include/time.h
+++ b/newlib/libc/include/time.h
@@ -62,6 +62,9 @@ time_t	   time (time_t *_timer);
 
 int        timespec_get(struct timespec *ts, int base);
 #endif
+#if (__ISO_C_VISIBLE >= 2023)
+int        timespec_getres(struct timespec *ts, int base);
+#endif
 #ifndef _REENT_ONLY
 char	  *asctime (const struct tm *_tblock);
 char	  *ctime (const time_t *_time);