diff --git a/cfg/std.cfg b/cfg/std.cfg
index f50ab5eff..6266f35ca 100644
--- a/cfg/std.cfg
+++ b/cfg/std.cfg
@@ -2362,7 +2362,9 @@
     <returnValue type="size_t"/>
     <noreturn>false</noreturn>
     <leak-ignore/>
-    <arg nr="1" direction="out"/>
+    <arg nr="1" direction="out">
+      <not-uninit indirect="1"/>
+    </arg>
     <arg nr="2" direction="in">
       <not-null/>
       <not-uninit/>
diff --git a/test/cfg/std.c b/test/cfg/std.c
index 38b8002ff..6f278789f 100644
--- a/test/cfg/std.c
+++ b/test/cfg/std.c
@@ -1651,14 +1651,23 @@ void uninitvar_mbstowcs(void)
     (void)mbstowcs(ws,s,n);
 }
 
-void uninitvar_mbsrtowcs(void)
+void uninitvar_mbsrtowcs(wchar_t* d, const char** s, size_t m, mbstate_t *p)
 {
     wchar_t* dest;
     const char* src;
     size_t max;
     mbstate_t* ps;
     // cppcheck-suppress uninitvar
-    (void)mbsrtowcs(dest,&src,max,ps);
+    (void)mbsrtowcs(dest,s,m,p);
+    // cppcheck-suppress uninitvar
+    (void)mbsrtowcs(dest,&src,m,p);
+    // cppcheck-suppress uninitvar
+    (void)mbsrtowcs(dest,s,max,p);
+    // cppcheck-suppress uninitvar
+    (void)mbsrtowcs(dest,s,m,ps);
+
+    // No warning is expected
+    (void)mbsrtowcs(d,s,m,p);
 }
 
 void uninitvar_wctob(void)