diff --git a/cfg/std.cfg b/cfg/std.cfg
index 164371ca7..c0c5dbbe3 100644
--- a/cfg/std.cfg
+++ b/cfg/std.cfg
@@ -2312,6 +2312,7 @@
     </arg>
     <arg nr="3" direction="inout">
       <not-uninit/>
+      <not-null/>
     </arg>
   </function>
   <!-- wint_t btowc(int c); -->
diff --git a/test/cfg/std.c b/test/cfg/std.c
index 26f02bba8..3dce3c204 100644
--- a/test/cfg/std.c
+++ b/test/cfg/std.c
@@ -1598,6 +1598,15 @@ void uninitvar_mbrlen(const char* p, size_t m, mbstate_t* s)
     (void)mbrlen(p,m,s);
 }
 
+void nullPointer_mbrlen(const char* p, size_t m, mbstate_t* s)
+{
+    /* no warning is expected: A call to the function with a null pointer as pmb resets the shift state (and ignores parameter max). */
+    (void)mbrlen(NULL,m,s);
+    (void)mbrlen(NULL,0,s);
+    /* cppcheck-suppress nullPointer */
+    (void)mbrlen(p,m,NULL);
+}
+
 void uninitvar_btowc(void)
 {
     int c;
diff --git a/test/cfg/std.cpp b/test/cfg/std.cpp
index a61e8e7c7..d9cd7b261 100644
--- a/test/cfg/std.cpp
+++ b/test/cfg/std.cpp
@@ -1106,6 +1106,15 @@ void uninitvar_mbrlen(const char* p, size_t m, mbstate_t* s)
     (void)std::mbrlen(p,m,s);
 }
 
+void nullPointer_mbrlen(const char* p, size_t m, mbstate_t* s)
+{
+    // no warning is expected: A call to the function with a null pointer as pmb resets the shift state (and ignores parameter max).
+    (void)std::mbrlen(NULL,m,s);
+    (void)std::mbrlen(NULL,0,s);
+    // cppcheck-suppress nullPointer
+    (void)std::mbrlen(p,m,NULL);
+}
+
 void uninitvar_btowc(void)
 {
     int c;