diff --git a/sys/contrib/ipfilter/netinet/ip_proxy.h b/sys/contrib/ipfilter/netinet/ip_proxy.h
index 659b0a7ebe27..c6a77ba4ebee 100644
--- a/sys/contrib/ipfilter/netinet/ip_proxy.h
+++ b/sys/contrib/ipfilter/netinet/ip_proxy.h
@@ -13,7 +13,7 @@
 #define	__IP_PROXY_H__
 
 #ifndef	SOLARIS
-# if defined(sun) && defined(__SVR4))
+# if defined(sun) && defined(__SVR4)
 #  define	SOLARIS		1
 # else
 #  define	SOLARIS		0