diff --git a/cfg/windows.cfg b/cfg/windows.cfg
index c619f38c1..eda1d18de 100644
--- a/cfg/windows.cfg
+++ b/cfg/windows.cfg
@@ -1388,6 +1388,21 @@
     </arg>
     <warn severity="style" reason="Obsolete" alternatives="RtlFillMemory"/>
   </function>
+  <!-- int _iswctype( wint_t wc, wctype_t desc ); -->
+  <function name="_iswctype">
+    <use-retval/>
+    <pure/>
+    <returnValue type="int"/>
+    <noreturn>false</noreturn>
+    <leak-ignore/>
+    <arg nr="1" direction="in">
+      <not-uninit/>
+    </arg>
+    <arg nr="2" direction="in">
+      <not-uninit/>
+    </arg>
+    <warn severity="style" reason="Obsolete" alternatives="iswctype"/>
+  </function>
   <!--PVOID RtlSecureZeroMemory(
   _Out_ PVOID  ptr,
   _In_  SIZE_T cnt);-->