diff --git a/cfg/std.cfg b/cfg/std.cfg
index 3d4331fda..4b3a93fb0 100644
--- a/cfg/std.cfg
+++ b/cfg/std.cfg
@@ -4724,6 +4724,7 @@ The obsolete function 'gets' is called. With 'gets' you'll get a buffer overrun
     <returnValue type="size_t"/>
     <noreturn>false</noreturn>
     <leak-ignore/>
+    <!-- In case the 3rd argument is 0, the 1st argument is permitted to be a null pointer. (#6306) -->
     <arg nr="2">
       <not-null/>
       <not-uninit/>
@@ -4738,9 +4739,7 @@ The obsolete function 'gets' is called. With 'gets' you'll get a buffer overrun
     <returnValue type="size_t"/>
     <noreturn>false</noreturn>
     <leak-ignore/>
-    <arg nr="1">
-      <not-null/>
-    </arg>
+    <!-- In case the 3rd argument is 0, the 1st argument is permitted to be a null pointer. (#6306) -->
     <arg nr="2">
       <not-null/>
       <not-uninit/>