remove fragile union design

Absurd to be memory-conscious about a couple of member variables in an object that represents user input

libs/ardour/ardour/transport_fsm.h

@@ -44,21 +44,20 @@ struct TransportFSM
 
 	struct Event : public boost::intrusive::list_base_hook<> {
 		EventType type;
-		union {
-			bool abort; /* for stop */
-			LocateTransportDisposition ltd; /* for locate */
-		};
-		union {
-			bool clear_state; /* for stop */
-			bool with_flush; /* for locate */
-		};
+		/* for stop */
+		bool abort;
+		bool clear_state;
 		/* for locate */
+		LocateTransportDisposition ltd;
+		bool with_flush;
 		samplepos_t target;
 		bool for_loop_end;
 		bool force;
 
 		Event (EventType t)
 			: type (t)
+			, abort (false)
+			, clear_state (false)
 			, ltd (MustStop)
 			, with_flush (false)
 			, target (0)
@@ -72,11 +71,18 @@ struct TransportFSM
 			: type (t)
 			, abort (ab)
 			, clear_state (cl)
+			, ltd (MustStop)
+			, with_flush (false)
+			, target (0)
+			, for_loop_end (false)
+			, force (false)
 		{
 			assert (t == StopTransport);
 		}
 		Event (EventType t, samplepos_t pos, LocateTransportDisposition l, bool fl, bool lp, bool f4c)
 			: type (t)
+			, abort (false)
+			, clear_state (false)
 			, ltd (l)
 			, with_flush (fl)
 			, target (pos)