Index: xgas.h
--- xgas.h.orig
+++ xgas.h
@@ -17,6 +17,8 @@
 #include <X11/Xutil.h>
 #include <X11/Xlib.h>
 #include <math.h>
+#include <stdio.h>
+#include <stdlib.h>
 
 /* Force the numerical instability out into the open */
 #define double float
