diff --git a/rtl/win64/classes.pp b/rtl/win64/classes.pp
index 04de6cd4d9..cc9ca67add 100644
--- a/rtl/win64/classes.pp
+++ b/rtl/win64/classes.pp
@@ -35,7 +35,10 @@ type
 function MakeObjectInstance(Method: TWndMethod): Pointer;
 procedure FreeObjectInstance(ObjectInstance: Pointer);
 
-  {$i classesh.inc}
+function AllocateHWnd(Method: TWndMethod): HWND;
+procedure DeallocateHWnd(Wnd: HWND);
+
+{$i classesh.inc}
 
 implementation
 
@@ -57,6 +60,18 @@ procedure FreeObjectInstance(ObjectInstance: Pointer);
   end;
 
 
+function AllocateHWnd(Method: TWndMethod): HWND;
+  begin
+    runerror(211);
+  end;
+
+
+procedure DeallocateHWnd(Wnd: HWND);
+  begin
+    runerror(211);
+  end;
+
+
 initialization
   CommonInit;