diff -upr ex-070224.orig/ex_vis.h ex-070224/ex_vis.h
--- ex-070224.orig/ex_vis.h	2005-08-06 14:41:15.000000000 +0300
+++ ex-070224/ex_vis.h	2015-05-02 20:41:13.938665281 +0300
@@ -104,7 +104,7 @@ var enum {
  */
 var	short	TUBELINES;
 var	short	TUBECOLS;
-var	short	TUBESIZE;
+var	int	TUBESIZE;
 
 /*
  * The screen in visual and crtopen is of varying size; the basic