weird mc crash

2015-10-11 00:19:00.487 java[12323:209981] *** Collection <__NSSetM: 0x7fdf44c84320> was mutated while being enumerated.
2015-10-11 00:19:00.682 java[12323:209981] (
    0   CoreFoundation                      0x00007fff8f41ebd2 __exceptionPreprocess + 178
    1   libobjc.A.dylib                     0x00007fff92d27dd4 objc_exception_throw + 48
    2   CoreFoundation                      0x00007fff8f48509c __NSFastEnumerationMutationHandler + 300
    3   AppKit                              0x00007fff94722505 -[NSView trackingAreas] + 278
    4   AppKit                              0x00007fff9483d12b -[NSView(NSInternal) _updateTrackingAreas] + 391
    5   AppKit                              0x00007fff94ee3ad0 ___NSWindowGetDisplayCycleObserver_block_invoke6334 + 1265
    6   AppKit                              0x00007fff9489319e __37+[NSDisplayCycle currentDisplayCycle]_block_invoke19 + 292
    7   QuartzCore                          0x00007fff9436491d _ZN2CA11Transaction19run_commit_handlersE18CATransactionPhase + 85
    8   QuartzCore                          0x00007fff943646c7 _ZN2CA7Context18commit_transactionEPNS_11TransactionE + 2447
    9   QuartzCore                          0x00007fff94363a98 _ZN2CA11Transaction6commitEv + 508
    10  QuartzCore                          0x00007fff9436f28f _ZN2CA11Transaction17observer_callbackEP19__CFRunLoopObservermPv + 71
    11  CoreFoundation                      0x00007fff8f3b3e07 __CFRUNLOOP_IS_CALLING_OUT_TO_AN_OBSERVER_CALLBACK_FUNCTION__ + 23
    12  CoreFoundation                      0x00007fff8f3b3d77 __CFRunLoopDoObservers + 391
    13  CoreFoundation                      0x00007fff8f392d58 CFRunLoopRunSpecific + 328
    14  HIToolbox                           0x00007fff88fc0d55 RunCurrentEventLoopInMode + 235
    15  HIToolbox                           0x00007fff88fc0b8f ReceiveNextEventCommon + 432
    16  HIToolbox                           0x00007fff88fc09cf _BlockUntilNextEventMatchingListInModeWithFilter + 71
    17  AppKit                              0x00007fff9470d236 _DPSNextEvent + 1067
    18  AppKit                              0x00007fff9470c665 -[NSApplication _nextEventMatchingEventMask:untilDate:inMode:dequeue:] + 454
    19  libosxapp.dylib                     0x0000000123fdc3aa -[NSApplicationAWT nextEventMatchingMask:untilDate:inMode:dequeue:] + 124
    20  AppKit                              0x00007fff947011c8 -[NSApplication run] + 682
    21  libosxapp.dylib                     0x0000000123fdc14d +[NSApplicationAWT runAWTLoopWithApp:] + 156
    22  libawt_lwawt.dylib                  0x0000000124b2a517 -[AWTStarter starter:] + 905
    23  Foundation                          0x00007fff916ff54e __NSThreadPerformPerform + 279
    24  CoreFoundation                      0x00007fff8f3b4621 __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION__ + 17
    25  CoreFoundation                      0x00007fff8f393e1c __CFRunLoopDoSources0 + 556
    26  CoreFoundation                      0x00007fff8f39333f __CFRunLoopRun + 927
    27  CoreFoundation                      0x00007fff8f392d38 CFRunLoopRunSpecific + 296
    28  java                                0x000000010cfd3463 CreateExecutionEnvironment + 871
    29  java                                0x000000010cfcf1ac JLI_Launch + 1952
    30  java                                0x000000010cfd54c0 main + 101
    31  java                                0x000000010cfcea04 start + 52
    32  ???                                 0x0000000000000023 0x0 + 35
)