Update struct fields to ensure 64-bit alignment

lib/reversetunnel/conn.go

@@ -45,6 +45,10 @@ type connKey struct {
 
 // remoteConn holds a connection to a remote host, either node or proxy.
 type remoteConn struct {
+	// lastHeartbeat is the last time a heartbeat was received.
+	// this field is intentionally placed first to ensure 64-bit alignment
+	lastHeartbeat int64
+
 	*connConfig
 	mu  sync.Mutex
 	log *logrus.Entry
@@ -68,9 +72,6 @@ type remoteConn struct {
 
 	// clock is used to control time in tests.
 	clock clockwork.Clock
-
-	// lastHeartbeat is the last time a heartbeat was received.
-	lastHeartbeat int64
 }
 
 // connConfig is the configuration for the remoteConn.

lib/srv/keepalive_test.go

@@ -123,8 +123,8 @@ func waitForRequests(requestSender *testRequestSender, count int) error {
 }
 
 type testRequestSender struct {
+	count int64 // intentionally placed first to ensure 64-bit alignment
 	reply bool
-	count int64
 }
 
 func (n *testRequestSender) SendRequest(name string, wantReply bool, payload []byte) (bool, []byte, error) {