$NetBSD: patch-ap,v 1.2 2021/07/04 07:57:13 jnemeth Exp $

--- libmilter/sm_gethost.c.orig	2020-05-19 19:54:32.000000000 +0000
+++ libmilter/sm_gethost.c
@@ -64,15 +64,15 @@ sm_getipnodebyname(name, family, flags, 
 	if (family == AF_INET6)
 	{
 		/* From RFC2133, section 6.1 */
-		resv6 = bitset(RES_USE_INET6, _res.options);
-		_res.options |= RES_USE_INET6;
+		resv6 = bitset(RES_USE_INET6, sm_res.options);
+		sm_res.options |= RES_USE_INET6;
 	}
 #  endif /* RES_USE_INET6 */
 	SM_SET_H_ERRNO(0);
 	h = gethostbyname(name);
 #  ifdef RES_USE_INET6
 	if (!resv6)
-		_res.options &= ~RES_USE_INET6;
+		sm_res.options &= ~RES_USE_INET6;
 #  endif
 
 	/* the function is supposed to return only the requested family */
