diff --git a/libs/ardour/session_command.cc b/libs/ardour/session_command.cc
index 2fdcfb17a2..f2909ea10d 100644
--- a/libs/ardour/session_command.cc
+++ b/libs/ardour/session_command.cc
@@ -84,8 +84,8 @@ Session::memento_command_factory(XMLNode *n)
     }
 
     if (!child) {
-	error << _("Tried to reconstitute a MementoCommand with no contents, failing. id=%1") << id.to_s() << endmsg;
-	return 0;
+	    error << string_compose (_("Tried to reconstitute a MementoCommand with no contents, failing. id=%1"), id.to_s()) << endmsg;
+	    return 0;
     }
 
     /* create command */