From 4405ac7386605672d1439e2bc830e5f67b856e07 Mon Sep 17 00:00:00 2001
From: Jakob Borg <jakob@nym.se>
Date: Sun, 23 Aug 2015 15:50:57 +0200
Subject: [PATCH] Report reason for no IPv6 multicast with STTRACE=discover

---
 lib/discover/discover.go | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/lib/discover/discover.go b/lib/discover/discover.go
index da63d60d..f979c398 100644
--- a/lib/discover/discover.go
+++ b/lib/discover/discover.go
@@ -102,6 +102,9 @@ func (d *Discoverer) startLocalIPv4Broadcasts(localPort int) {
 func (d *Discoverer) startLocalIPv6Multicasts(localMCAddr string) {
 	mb, err := beacon.NewMulticast(localMCAddr)
 	if err != nil {
+		if debug {
+			l.Debugln("beacon.NewMulticast:", err)
+		}
 		l.Infoln("Local discovery over IPv6 unavailable")
 		return
 	}