Please file a radar with more information about your project/machine/OS. A small reproducible project would also be useful.
You can check the system log to see if there were any crashes of a process called LeakAgent. If there was, attaching that would also be helpful.
11:03:39.600684 +0900 SubmitDiagInfo Submitted problem report file:///Users/user/Library/Logs/DiagnosticReports/LeakAgent_2016-09-29-111632.crash
I found this entry in the log. It seems it's already been filed and I can't reproduce the problem with sample project. Would it still help if I filed the radar with the log?