fix ARM unsafe access

Signed-off-by: Victor Vieux <vieux@docker.com>

vendor.conf

@@ -23,7 +23,7 @@ github.com/RackSec/srslog 365bf33cd9acc21ae1c355209865f17228ca534e
 github.com/imdario/mergo 0.2.1
 
 #get libnetwork packages
-github.com/docker/libnetwork 1861587d0fe7cdf85b89160ed36f20b81e96528d
+github.com/docker/libnetwork 57be722e077059d1ee0539be31743a3642ccbeb3
 github.com/docker/go-events 18b43f1bc85d9cdd42c05a6cd2d444c7a200a894
 github.com/armon/go-radix e39d623f12e8e41c7b5529e9a9dd67a1e2261f80
 github.com/armon/go-metrics eb0af217e5e9747e41dd5303755356b62d28e3ec

vendor/github.com/docker/libnetwork/networkdb/networkdb.go

@@ -24,6 +24,15 @@ const (
 // NetworkDB instance drives the networkdb cluster and acts the broker
 // for cluster-scoped and network-scoped gossip and watches.
 type NetworkDB struct {
+	// The clocks MUST be the first things
+	// in this struct due to Golang issue #599.
+
+	// Global lamport clock for node network attach events.
+	networkClock serf.LamportClock
+
+	// Global lamport clock for table events.
+	tableClock serf.LamportClock
+
 	sync.RWMutex
 
 	// NetworkDB configuration.
@@ -59,12 +68,6 @@ type NetworkDB struct {
 	// waiting for an ack.
 	bulkSyncAckTbl map[string]chan struct{}
 
-	// Global lamport clock for node network attach events.
-	networkClock serf.LamportClock
-
-	// Global lamport clock for table events.
-	tableClock serf.LamportClock
-
 	// Broadcast queue for network event gossip.
 	networkBroadcasts *memberlist.TransmitLimitedQueue