asn.h: Guard against being included twice.

In order to surpress a warning on clang.

diff --git a/asn.h b/asn.h
index dd2d4407e3460e0bd76aae3819851c7c2d01a77f..803a099a626e17075c58c62bb2a37b250fb12a11 100644 (file)
--- a/asn.h
+++ b/asn.h
@@ -25,8 +25,9 @@
 // It will evaluate to nothing if we don't need it. 
 
 #ifndef NO_IPINFO
-#define IPINFO
 
+#ifndef IPINFO
+#define IPINFO
 
 extern int ipinfo_no;
 extern int ipinfo_max;
@@ -38,4 +39,5 @@ char *fmt_ipinfo(ip_t *addr);
 int get_iiwidth(void);
 int is_printii(void);
 
-#endif
+#endif /* IPINFO */
+#endif /* NO_IPINFO */