X-Git-Url: https://main.carlh.net/gitweb/?a=blobdiff_plain;f=libs%2Fardour%2Fslavable_automation_control.cc;h=d4002343e881e48909eb37e7c54b0da16e00d4a4;hb=91ab5e31751105d59386aab6a6e16ac5582904dc;hp=8c50863d954235c0a6f67fd7498d5ad9b8fc74cc;hpb=51064f77a874f15c2cebd4fed12996177f951936;p=ardour.git

diff --git a/libs/ardour/slavable_automation_control.cc b/libs/ardour/slavable_automation_control.cc
index 8c50863d95..d4002343e8 100644
--- a/libs/ardour/slavable_automation_control.cc
+++ b/libs/ardour/slavable_automation_control.cc
@@ -139,10 +139,18 @@ SlavableAutomationControl::add_master (boost::shared_ptr<AutomationControl> m)
 			   itself.
 			*/
 
-			m->DropReferences.connect_same_thread (masters_connections, boost::bind (&SlavableAutomationControl::master_going_away, this, m));
+			m->DropReferences.connect_same_thread (masters_connections, boost::bind (&SlavableAutomationControl::master_going_away, this, boost::weak_ptr<AutomationControl>(m)));
 
-			/* Store the connection inside the MasterRecord, so that when we destroy it, the connection is destroyed
-			   and we no longer hear about changes to the AutomationControl.
+			/* Store the connection inside the MasterRecord, so
+			   that when we destroy it, the connection is destroyed
+			   and we no longer hear about changes to the
+			   AutomationControl. 
+
+			   Note that this also makes it safe to store a
+			   boost::shared_ptr<AutomationControl> in the functor,
+			   since we know we will destroy the functor when the 
+			   connection is destroyed, which happens when we
+			   disconnect from the master (for any reason).
 
 			   Note that we fix the "from_self" argument that will
 			   be given to our own Changed signal to "false",
@@ -246,13 +254,18 @@ SlavableAutomationControl::remove_master (boost::shared_ptr<AutomationControl> m
 		Glib::Threads::RWLock::WriterLock lm (master_lock);
 		current_value = get_value_locked ();
 		erased = _masters.erase (m->id());
-		if (erased) {
+		if (erased && !_session.deletion_in_progress()) {
 			recompute_masters_ratios (current_value);
 		}
 		masters_left = _masters.size ();
 		new_value = get_value_locked ();
 	}
 
+	if (_session.deletion_in_progress()) {
+		/* no reason to care about new values or sending signals */
+		return;
+	}
+
 	if (erased) {
 		MasterStatusChange (); /* EMIT SIGNAL */
 	}