silence compiler warning

diff --git a/lib/dns/resolver.c b/lib/dns/resolver.c
index 43c746dbb7d094c2e44f3de2f53e75f0dcb917da..4e869d73ef33d9d105b9622c9ceaf8b10e891577 100644 (file)
--- a/lib/dns/resolver.c
+++ b/lib/dns/resolver.c
@@ -7682,9 +7682,21 @@ resquery_response(isc_task_t *task, isc_event_t *event) {
                        }
                        /*
                         * XXXMPA we should really test against the version of
-                        * EDNS we sent in the request.
+                        * EDNS we sent in the request.  Some servers return
+                        * BADVERS for unknown EDNS options.
+                        * RFC 2671 was not clear that they should be ignored.
+                        * RFC 6891 is clear that that they should be ignored.
+                        * If we are supporting EDNS > 0 then perform strict
+                        * version checking of badvers responses.  We won't
+                        * be sending SIT etc. in that case.
                         */
-                       if (version < DNS_EDNS_VERSION) {
+#if DNS_EDNS_VERSION == 0
+                        /* Avoids a compiler warning with < 0 */
+                       if (version <= DNS_EDNS_VERSION)
+#else
+                       if (version < DNS_EDNS_VERSION)
+#endif
+                       {
                                dns_adb_changeflags(fctx->adb, query->addrinfo,
                                                    flags, mask);
                        } else {