diff --git a/hping3/hping2.h b/hping3/hping2.h
index 70e2035..3766e1d 100644
--- a/hping3/hping2.h
+++ b/hping3/hping2.h
@@ -353,7 +353,7 @@ struct delaytable_element {
 	int status;
 };
 
-volatile struct delaytable_element delaytable[TABLESIZE];
+extern volatile struct delaytable_element delaytable[TABLESIZE];
 
 /* protos */
 void	nop(void);				/* nop */