Fix #12060 (#12076)

src/generators/gencpp.ml

@@ -4412,7 +4412,7 @@ let current_virtual_functions_rev clazz base_functions =
       | TFun (args,return_type), Method _  ->
           if (is_override elem ) then
             if List.exists (fun (e,a,r) -> e.cf_name=elem.cf_name ) result then
-               result
+               List.map (fun (e,a,r) -> if e.cf_name<>elem.cf_name then (e,a,r) else (elem,args,return_type) ) result
             else
                (elem,args,return_type) :: result
           else