Help/OBJC_STANDARD: Document Objective C17 and C23 support
This was missed in
* commit 93b7d3d292 (C17 support, 2021-02-06, v3.21.0-rc1~587^2~10)
* commit dcd599757f (C23 support, 2021-02-06, v3.21.0-rc1~587^2~9)
Fixes: #25746
diff --git a/Help/prop_tgt/OBJC_STANDARD.rst b/Help/prop_tgt/OBJC_STANDARD.rst
index 0609239..a3c5653 100644
--- a/Help/prop_tgt/OBJC_STANDARD.rst
+++ b/Help/prop_tgt/OBJC_STANDARD.rst
@@ -20,6 +20,16 @@
``11``
Objective C11
+``17``
+ .. versionadded:: 3.21
+
+ Objective C17
+
+``23``
+ .. versionadded:: 3.21
+
+ Objective C23
+
If the value requested does not result in a compile flag being added for
the compiler in use, a previous standard flag will be added instead. This
means that using:
