diff --git a/cfg/std.cfg b/cfg/std.cfg
index 399f85e5f..f93c5e0ed 100644
--- a/cfg/std.cfg
+++ b/cfg/std.cfg
@@ -7924,7 +7924,9 @@ initializer list (7) string& replace (const_iterator i1, const_iterator i2, init
       <not-null/>
     </arg>
     <arg nr="2"/>
-    <arg nr="3"/>
+    <arg nr="3" direction="in">
+      <not-uninit/>
+    </arg>
   </function>
   <!-- thrd_t thrd_current(void); // since C11 -->
   <function name="thrd_current">