From bb8667e13b728d0584c21c30daac9bc517b6e300 Mon Sep 17 00:00:00 2001
From: Meco Man <920369182@qq.com>
Date: Sun, 5 Nov 2023 20:53:02 -0500
Subject: [PATCH] [rtdef] add comment for RT_USING_LIBC_ISO_ONLY (#8229)

---
 include/rtdef.h | 1 +
 1 file changed, 1 insertion(+)

diff --git a/include/rtdef.h b/include/rtdef.h
index 10edc25df1..2f55651262 100644
--- a/include/rtdef.h
+++ b/include/rtdef.h
@@ -62,6 +62,7 @@
 
 #ifdef RT_USING_LIBC
 #if !defined(RT_USING_LIBC_ISO_ONLY) && !defined(RT_VER_NUM)
+/* If RT_VER_NUM is not defined, there is no extra libc support. */
 #define RT_USING_LIBC_ISO_ONLY  (1)
 #else
 #define RT_USING_LIBC_ISO_ONLY  (0)