Index: add_window.c
--- add_window.c.orig
+++ add_window.c
@@ -43,6 +43,7 @@ static char RCSinfo[]=
 #endif
 
 #include <stdio.h>
+#include <stdlib.h>
 #include "twm.h"
 #include <X11/Xatom.h>
 #include "add_window.h"
@@ -55,6 +56,7 @@ static char RCSinfo[]=
 #include "screen.h"
 #include "iconmgr.h"
 #include "move.h"
+#include "vdt.h"
 
 #define gray_width 2
 #define gray_height 2