QFileDialog crashes sporadically

Sometimes when I open a file dialog, my application crashes. Sample dump:

Thread 0 Crashed:
0 ??? 0x0000000000000003 0 + 3
1 com.apple.FinderKit 0x00007fff878b0a27 AppBundleIDCanOpenExtension(TString const&, TString const&) + 392
2 com.apple.FinderKit 0x00007fff878b114d ThisAppCanOpenExtension(TString const&) + 208
3 com.apple.FinderKit 0x00007fff878b154f -[FIFinderViewGutsController finderLocationPopUpWillDisplay:] + 183
4 com.apple.FinderKit 0x00007fff878db7ff -[FILocationPopUp menuNeedsUpdate:] + 46
5 com.apple.AppKit 0x00007fff88f756a8 -[NSMenu _populateFromDelegateWithEventRef:] + 674
6 com.apple.AppKit 0x00007fff88f19e64 -[NSMenu _populateWithEventRef:] + 83
7 com.apple.AppKit 0x00007fff88f746ac -[NSCarbonMenuImpl _carbonPopulateEvent:handlerCallRef:] + 427
8 com.apple.AppKit 0x00007fff88f74245 NSSLMMenuEventHandler + 342
9 com.apple.HIToolbox 0x00007fff87c07f0a DispatchEventToHandlers(EventTargetRec*, OpaqueEventRef*, HandlerCallRec*) + 1206
10 com.apple.HIToolbox 0x00007fff87c073d9 SendEventToEventTargetInternal(OpaqueEventRef*, OpaqueEventTargetRef*, HandlerCallRec*) + 410
11 com.apple.HIToolbox 0x00007fff87c07236 SendEventToEventTargetWithOptions + 43
12 com.apple.HIToolbox 0x00007fff87c50d58 SendMenuPopulate(MenuData*, OpaqueEventTargetRef*, unsigned int, double, unsigned int, OpaqueEventRef*, unsigned char*) + 279
13 com.apple.HIToolbox 0x00007fff87bd9d5a SendMenuOpening(MenuSelectData*, MenuData*, double, unsigned int, unsigned int, __CFDictionary*, unsigned char, unsigned char*) + 286
14 com.apple.HIToolbox 0x00007fff87d6ecff PopUpMenuSelectCore(MenuData*, Point, double, Point, unsigned short, unsigned int, Rect const*, unsigned short, unsigned int, Rect const*, Rect const*, __CFString const*, OpaqueMenuRef*, unsigned short) + 895
15 com.apple.HIToolbox 0x00007fff87d6e924 _HandlePopUpMenuSelection7 + 629
16 com.apple.AppKit 0x00007fff88ff761b _NSSLMPopUpCarbonMenu3 + 3916
17 com.apple.AppKit 0x00007fff89358d2a _NSPopUpCarbonMenu3 + 39
18 com.apple.AppKit 0x00007fff88ff65dc -[NSCarbonMenuImpl popUpMenu:atLocation:width:forView:withSelectedItem:withFont:withFlags:withOptions:] + 346
19 com.apple.AppKit 0x00007fff891ba315 -[NSPopUpButtonCell trackMouse:inRect:ofView:untilMouseUp:] + 540
20 com.apple.AppKit 0x00007fff88e42c9c -[NSControl mouseDown:] + 820
21 com.apple.AppKit 0x00007fff88e3a60e -[NSWindow sendEvent:] + 6853
22 com.apple.AppKit 0x00007fff88e36744 -[NSApplication sendEvent:] + 5761
23 QtGui 0x0000000112baeb7e -[QNSApplication sendEvent:] + 78
24 com.apple.AppKit 0x00007fff88f9f76a -[NSApplication _realDoModalLoop:peek:] + 582
25 com.apple.AppKit 0x00007fff88f9f9ce -[NSApplication runModalForWindow:] + 120
26 com.apple.AppKit 0x00007fff891eadb6 -[NSSavePanel runModal] + 302
27 QtGui 0x0000000112be81da -[QNSOpenSavePanelDelegate runApplicationModalPanel] + 266
28 QtGui 0x0000000112bea70f QFileDialogPrivate::_q_macRunNativeAppModalPanel() + 63
29 QtGui 0x0000000113038c0b QFileDialog::qt_static_metacall(QObject*, QMetaObject::Call, int, void**) + 1067
30 QtCore 0x0000000113a7cf23 QMetaObject::activate(QObject*, QMetaObject const*, int, void**) + 2259
31 QtCore 0x0000000113a81f32 QSingleShotTimer::timerEvent(QTimerEvent*) + 50
32 QtCore 0x0000000113a78663 QObject::event(QEvent*) + 51
33 QtGui 0x0000000112c011af QApplicationPrivate::notify_helper(QObject*, QEvent*) + 255
34 QtGui 0x0000000112c041ae QApplication::notify(QObject*, QEvent*) + 7470
35 QtCore 0x0000000113a65e41 QCoreApplication::notifyInternal(QObject*, QEvent*) + 113
36 QtGui 0x0000000112c0489c qt_sendSpontaneousEvent(QObject*, QEvent*) + 44
37 QtGui 0x0000000112bb673b QEventDispatcherMacPrivate::activateTimer(__CFRunLoopTimer*, void*) + 187
38 com.apple.CoreFoundation 0x00007fff900b4da4 _CFRUNLOOP_IS_CALLING_OUT_TO_A_TIMER_CALLBACK_FUNCTION_ + 20
39 com.apple.CoreFoundation 0x00007fff900b48bd __CFRunLoopDoTimer + 557
40 com.apple.CoreFoundation 0x00007fff9009a099 __CFRunLoopRun + 1513
41 com.apple.CoreFoundation 0x00007fff900996b2 CFRunLoopRunSpecific + 290
42 com.apple.HIToolbox 0x00007fff87c2f0a4 RunCurrentEventLoopInMode + 209
43 com.apple.HIToolbox 0x00007fff87c2ed84 ReceiveNextEventCommon + 166
44 com.apple.HIToolbox 0x00007fff87c2ecd3 BlockUntilNextEventMatchingListInMode + 62
45 com.apple.AppKit 0x00007fff88d55613 _DPSNextEvent + 685
46 com.apple.AppKit 0x00007fff88d54ed2 -[NSApplication nextEventMatchingMask:untilDate:inMode:dequeue:] + 128
47 com.apple.AppKit 0x00007fff88d4c283 -[NSApplication run] + 517
48 QtGui 0x0000000112bb7733 QEventDispatcherMac::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) + 1219
49 QtCore 0x0000000113a63485 QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) + 501
50 QtGui 0x0000000113024b22 QDialog::exec() + 258
51 QtGui 0x0000000113030409 QFileDialog::getSaveFileName(QWidget*, QString const&, QString const&, QString const&, QString*, QFlags<QFileDialog::Option>) + 377