diff --git a/openslp-2.0.0-ifdef-slpv2.diff b/openslp-2.0.0-ifdef-slpv2.diff
new file mode 100644
index 0000000..57f6de3
--- /dev/null
+++ b/openslp-2.0.0-ifdef-slpv2.diff
@@ -0,0 +1,14 @@
+Index: openslp-2.0.0/slpd/slpd_process.c
+===================================================================
+--- openslp-2.0.0.orig/slpd/slpd_process.c
++++ openslp-2.0.0/slpd/slpd_process.c
+@@ -1055,7 +1055,9 @@ RESPOND:
+       if (truncate && size > truncate && G_SlpdProperty.hardMTU)
+       {
+          attrlistlen = 0;
++#ifdef ENABLE_SLPv2_SECURITY
+          opaqueauth = 0;
++#endif
+          size = message->header.langtaglen + 19; /* 14 bytes for header */
+          truncated = 1;
+       }
diff --git a/openslp.changes b/openslp.changes
index cedd85a..bafcf33 100644
--- a/openslp.changes
+++ b/openslp.changes
@@ -1,3 +1,9 @@
+-------------------------------------------------------------------
+Mon Aug 27 22:13:24 UTC 2018 - Jason Sikes <jsikes@suse.de>
+
+- Fixed failure to compile when ENABLE_SLPv2_SECURITY is not set
+  new patch: openslp-2.0.0-ifdef-slpv2.diff
+
 -------------------------------------------------------------------
 Wed Apr 11 14:39:03 CEST 2018 - mls@suse.de
 
diff --git a/openslp.spec b/openslp.spec
index f95856b..efb036d 100644
--- a/openslp.spec
+++ b/openslp.spec
@@ -12,7 +12,7 @@
 # license that conforms to the Open Source Definition (Version 1.9)
 # published by the Open Source Initiative.
 
-# Please submit bugfixes or comments via http://bugs.opensuse.org/
+# Please submit bugfixes or comments via https://bugs.opensuse.org/
 #
 
 
@@ -66,6 +66,7 @@ Patch17:        openslp.foldws.diff
 Patch18:        openslp.openssl-1.1.diff
 Patch19:        openslp.localaddr.diff
 Patch20:        openslp.tcpunicast.diff
+Patch21:        openslp-2.0.0-ifdef-slpv2.diff
 
 %description
 Service Location Protocol is an IETF standards track protocol that
@@ -138,6 +139,7 @@ such applications.
 %patch18 -p2
 %patch19
 %patch20
+%patch21 -p1
 
 %build
 autoreconf -fiv