title: Selector name found in current argument registers: isEqual:
body: <p>I am looking for some assistance with squashing a bug in an OSX app that i just can't work out. I am getting a logged error of:</p>
  
  <pre><code>Selector name found in current argument registers: isEqual:
  </code></pre>
  
  <p>But i can't for the life of me work out where it's coming from as the log is very unhelpful. Also i can't reproduce this on my own test systems, but it seems to be happening quite a lot on some of the beta testers machines. This only seems to happen on 10.9.</p>
  
  <p>Here is the log file for the crash:</p>
  
  <pre><code>Incident Identifier: 77FAD32D-0316-489E-B898-9C084A4FF48A
  CrashReporter Key:   A9FEF4E7-53F7-5FD1-AEDE-915C87BD437F
  Hardware Model:      MacBookPro8,1
  Process:         iModerate Deskto [4155]
  Path:            /Users/USER/Desktop/iModerate Desktop.app/Contents/MacOS/iModerate     Desktop
  Identifier:      com.fuzzybadger.iModerate-Desktop
  Version:         1.1.549
  Code Type:       X86-64
  Parent Process:  launchd [159]
  
  Date/Time:       2014-02-28 10:40:33 +0000
  OS Version:      Mac OS X 10.9.0 (13A603)
  Report Version:  104
  
  Exception Type:  SIGSEGV
  Exception Codes: SEGV_NOOP at 0x0
  Crashed Thread:  10
  
  Application Specific Information:
  Selector name found in current argument registers: isEqual:
  
  Thread 0:
  0   libsystem_kernel.dylib               0x00007fff852b1716 __psynch_cvwait + 10
  1   QuartzCore                           0x00007fff8769cce7 _ZN2CA13DispatchGroupD2Ev + 53
  2   QuartzCore                           0x00007fff8768916e _ZN2CA5Layer17display_if_neededEPNS_11TransactionE + 538
  3   QuartzCore                           0x00007fff876888f1 _ZN2CA5Layer28layout_and_display_if_neededEPNS_11TransactionE + 35
  4   QuartzCore                           0x00007fff8768837c _ZN2CA7Context18commit_transactionEPNS_11TransactionE + 236
  5   QuartzCore                           0x00007fff87688016 _ZN2CA11Transaction6commitEv + 388
  6   QuartzCore                           0x00007fff876987a1 _ZN2CA11Transaction17observer_callbackEP19__CFRunLoopObservermPv + 71
  7   CoreFoundation                       0x00007fff8998d0a7 __CFRUNLOOP_IS_CALLING_OUT_TO_AN_OBSERVER_CALLBACK_FUNCTION__ + 23
  8   CoreFoundation                       0x00007fff8998d017 __CFRunLoopDoObservers + 391
  9   CoreFoundation                       0x00007fff8997e294 CFRunLoopRunSpecific + 340
  10  HIToolbox                            0x00007fff8fbd1f0d RunCurrentEventLoopInMode + 226
  11  HIToolbox                            0x00007fff8fbd1b85 ReceiveNextEventCommon + 173
  12  HIToolbox                            0x00007fff8fbd1abc _BlockUntilNextEventMatchingListInModeWithFilter + 65
  13  AppKit                               0x00007fff8ce6828e _DPSNextEvent + 1434
  14  AppKit                               0x00007fff8ce678db -[NSApplication nextEventMatchingMask:untilDate:inMode:dequeue:] + 122
  15  AppKit                               0x00007fff8ce5b9cc -[NSApplication run] + 553
  16  AppKit                               0x00007fff8ce46803 NSApplicationMain + 940
  17  libdyld.dylib                        0x00007fff8ce435fd start + 1
  
  Thread 1:
  0   libsystem_kernel.dylib               0x00007fff852b2662 kevent64 + 10
  1   libdispatch.dylib                    0x00007fff91e9f152 _dispatch_mgr_init + 0
  
  Thread 2:
  0   libsystem_kernel.dylib               0x00007fff852ada1a mach_msg_trap + 10
  1   CoreFoundation                       0x00007fff8997f315 __CFRunLoopServiceMachPort + 181
  2   CoreFoundation                       0x00007fff8997e939 __CFRunLoopRun + 1161
  3   CoreFoundation                       0x00007fff8997e275 CFRunLoopRunSpecific + 309
  4   Foundation                           0x00007fff90e47907 +[NSURLConnection(Loader) _resourceLoadLoop:] + 348
  5   Foundation                           0x00007fff90e4770b __NSThread__main__ + 1318
  6   libsystem_pthread.dylib              0x00007fff905e8899 _pthread_body + 138
  7   libsystem_pthread.dylib              0x00007fff905e872a _pthread_struct_init + 0
  
  Thread 3:
  0   libsystem_kernel.dylib               0x00007fff852ada1a mach_msg_trap + 10
  1   CoreFoundation                       0x00007fff8997f315 __CFRunLoopServiceMachPort + 181
  2   CoreFoundation                       0x00007fff8997e939 __CFRunLoopRun + 1161
  3   CoreFoundation                       0x00007fff8997e275 CFRunLoopRunSpecific + 309
  4   AppKit                               0x00007fff8d0081ce _NSEventThread + 144
  5   libsystem_pthread.dylib              0x00007fff905e8899 _pthread_body + 138
  6   libsystem_pthread.dylib              0x00007fff905e872a _pthread_struct_init + 0
  
  Thread 4:
  0   libsystem_kernel.dylib               0x00007fff852ada1a mach_msg_trap + 10
  1   CoreFoundation                       0x00007fff8997f315 __CFRunLoopServiceMachPort + 181
  2   CoreFoundation                       0x00007fff8997e939 __CFRunLoopRun + 1161
  3   CoreFoundation                       0x00007fff8997e275 CFRunLoopRunSpecific + 309
  4   Foundation                           0x00007fff90e49a7c -[NSRunLoop(NSRunLoop) runMode:beforeDate:] + 253
  5   Simperium-OSX                        0x000000010cb6b838 -[_SRRunLoopThread main] (SRWebSocket.m:1744)
  6   Foundation                           0x00007fff90e4770b __NSThread__main__ + 1318
  7   libsystem_pthread.dylib              0x00007fff905e8899 _pthread_body + 138
  8   libsystem_pthread.dylib              0x00007fff905e872a _pthread_struct_init + 0
  
  Thread 5:
  0   libsystem_kernel.dylib               0x00007fff852b19aa __select + 10
  1   libsystem_pthread.dylib              0x00007fff905e8899 _pthread_body + 138
  2   libsystem_pthread.dylib              0x00007fff905e872a _pthread_struct_init + 0
  
  Thread 6:
  0   libsystem_kernel.dylib               0x00007fff852b1e6a __workq_kernreturn + 10
  1   libsystem_pthread.dylib              0x00007fff905ecfb9 start_wqthread + 13
  
  Thread 7:
  0   libsystem_kernel.dylib               0x00007fff852b1e6a __workq_kernreturn + 10
  1   libsystem_pthread.dylib              0x00007fff905ecfb9 start_wqthread + 13
  
  Thread 8:
  0   libsystem_platform.dylib             0x00007fff8bde7cd1 OSAtomicDequeue + 17
  1   libsystem_malloc.dylib               0x00007fff8f4b16c4 nano_malloc + 35
  2   libsystem_malloc.dylib               0x00007fff8f4af87c malloc_zone_malloc + 71
  3   CoreFoundation                       0x00007fff899118df __CFBasicHashRehash + 287
  4   CoreFoundation                       0x00007fff89917566 __CFBasicHashAddValue + 86
  5   CoreFoundation                       0x00007fff89916609 CFDictionarySetValue + 217
  6   libCGCMS.A.dylib                     0x00007fff8b857fb8 CreateProfileSet + 104
  7   libCGCMS.A.dylib                     0x00007fff8b857e61 profileRef + 189
  8   libCGCMS.A.dylib                     0x00007fff8b858b79 create + 1205
  9   libCGCMS.A.dylib                     0x00007fff8b859454 get_cms_space_for_space + 140
  10  libCGCMS.A.dylib                     0x00007fff8b8592ca get_color_world_for_space + 166
  11  libCGCMS.A.dylib                     0x00007fff8b8591f0 CMSTransformCreateConverter + 63
  12  CoreGraphics                         0x00007fff86681ba1 CGColorTransformCacheGetConversionType + 145
  13  CoreGraphics                         0x00007fff86681aeb CGColorTransformConvertNeedsCMS + 113
  14  CoreGraphics                         0x00007fff8667f8e9 img_data_lock + 1217
  15  CoreGraphics                         0x00007fff8667e480 CGSImageDataLock + 149
  16  libRIP.A.dylib                       0x00007fff86548b3c ripc_AcquireImage + 769
  17  libRIP.A.dylib                       0x00007fff86547b85 ripc_DrawImage + 1025
  18  CoreGraphics                         0x00007fff8667e023 CGContextDrawImage + 457
  19  AppKit                               0x00007fff8cfd8c02 __74-[NSImageRep drawInRect:fromRect:operation:fraction:respectFlipped:hints:]_block_invoke + 835
  20  AppKit                               0x00007fff8cfd86a8 -[NSImageRep drawInRect:fromRect:operation:fraction:respectFlipped:hints:] + 1073
  21  AppKit                               0x00007fff8cfd7fee __71-[NSImage drawInRect:fromRect:operation:fraction:respectFlipped:hints:]_block_invoke + 896
  22  AppKit                               0x00007fff8cf63626 -[NSImage _usingBestRepresentationForRect:context:hints:body:] + 170
  23  AppKit                               0x00007fff8cfd7b6c -[NSImage drawInRect:fromRect:operation:fraction:respectFlipped:hints:] + 1447
  24  AppKit                               0x00007fff8cfd7153 -[NSImage _drawMappingAlignmentRectToRect:withState:backgroundStyle:operation:fraction:flip:hints:] + 1453
  25  AppKit                               0x00007fff8d01fa21 -[NSImageCell _drawImageWithFrame:inView:] + 225
  26  AppKit                               0x00007fff8d01f8e5 -[NSImageCell drawInteriorWithFrame:inView:] + 625
  27  AppKit                               0x00007fff8cfd4728 -[NSControl drawRect:] + 341
  28  AppKit                               0x00007fff8cfc98b0 -[NSView(NSInternal) _recursive:displayRectIgnoringOpacity:inGraphicsContext:CGContext:topView:shouldChangeFontReferenceColor:] + 1075
  29  AppKit                               0x00007fff8cfc9bb0 -[NSView(NSInternal) _recursive:displayRectIgnoringOpacity:inGraphicsContext:CGContext:topView:shouldChangeFontReferenceColor:] + 1843
  30  AppKit                               0x00007fff8cfc9bb0 -[NSView(NSInternal) _recursive:displayRectIgnoringOpacity:inGraphicsContext:CGContext:topView:shouldChangeFontReferenceColor:] + 1843
  31  AppKit                               0x00007fff8cfc9bb0 -[NSView(NSInternal) _recursive:displayRectIgnoringOpacity:inGraphicsContext:CGContext:topView:shouldChangeFontReferenceColor:] + 1843
  32  AppKit                               0x00007fff8cfc936d __46-[NSView(NSLayerKitGlue) drawLayer:inContext:]_block_invoke + 186
  33  AppKit                               0x00007fff8cfc9153 -[NSView(NSLayerKitGlue) _drawViewBackingLayer:inContext:drawingHandler:] + 2297
  34  AppKit                               0x00007fff8cfc8848 -[NSView(NSLayerKitGlue) drawLayer:inContext:] + 108
  35  QuartzCore                           0x00007fff8768a852 CABackingStoreUpdate_ + 2220
  36  QuartzCore                           0x00007fff87689fa0 ___ZN2CA5Layer8display_Ev_block_invoke + 59
  37  QuartzCore                           0x00007fff87689f5c x_blame_allocations + 84
  38  QuartzCore                           0x00007fff87689a6b _ZN2CA5Layer8display_Ev + 1539
  39  AppKit                               0x00007fff8cfc8713 _NSBackingLayerDisplay + 235
  40  AppKit                               0x00007fff8cf9faab -[_NSViewBackingLayer display] + 811
  41  QuartzCore                           0x00007fff8769ce1a _ZL16display_callbackPvS_ + 81
  42  QuartzCore                           0x00007fff8769cd69 _ZN2CA13DispatchGroup8dispatchEb + 69
  43  libdispatch.dylib                    0x00007fff91e9d2ad _dispatch_client_callout + 8
  44  libdispatch.dylib                    0x00007fff91e9f09e _dispatch_root_queue_drain + 326
  45  libdispatch.dylib                    0x00007fff91ea0193 _dispatch_worker_thread2 + 40
  46  libsystem_pthread.dylib              0x00007fff905e9ef8 _pthread_wqthread + 314
  47  libsystem_pthread.dylib              0x00007fff905ecfb9 start_wqthread + 13
  
  Thread 9:
   0   libsystem_kernel.dylib               0x00007fff852b1e6a __workq_kernreturn + 10
  1   libsystem_pthread.dylib              0x00007fff905ecfb9 start_wqthread + 13
  
  Thread 10 Crashed:
  0   libobjc.A.dylib                      0x00007fff87f0e097 objc_msgSend + 23
  1   CoreFoundation                       0x00007fff899573d9 -[__NSDictionaryM setObject:forKey:] + 505
  2   AppKit                               0x00007fff8ceb032b -[NSCell _textAttributes] + 531
  3   AppKit                               0x00007fff8ceb00e2 -[NSCell _unformattedAttributedStringValue:] + 301
  4   AppKit                               0x00007fff8cfead57 -[NSButtonCell _currentTitle] + 122
  5   AppKit                               0x00007fff8cfea3fb -[NSButtonCell _configureAndDrawTitleWithRect:cellFrame:controlView:] + 148
  6   AppKit                               0x00007fff8cfd62cf -[NSButtonCell drawInteriorWithFrame:inView:] + 1965
  7   AppKit                               0x00007fff8cfd5ac8 -[NSButtonCell drawWithFrame:inView:] + 498
  8   AppKit                               0x00007fff8cfd4728 -[NSControl drawRect:] + 341
  9   AppKit                               0x00007fff8cfc98b0 -[NSView(NSInternal) _recursive:displayRectIgnoringOpacity:inGraphicsContext:CGContext:topView:shouldChangeFontReferenceColor:] + 1075
  10  AppKit                               0x00007fff8cfc9bb0 -[NSView(NSInternal) _recursive:displayRectIgnoringOpacity:inGraphicsContext:CGContext:topView:shouldChangeFontReferenceColor:] + 1843
  11  AppKit                               0x00007fff8cfc9bb0 -[NSView(NSInternal) _recursive:displayRectIgnoringOpacity:inGraphicsContext:CGContext:topView:shouldChangeFontReferenceColor:] + 1843
  12  AppKit                               0x00007fff8cfc9bb0 -[NSView(NSInternal) _recursive:displayRectIgnoringOpacity:inGraphicsContext:CGContext:topView:shouldChangeFontReferenceColor:] + 1843
  13  AppKit                               0x00007fff8cfc936d __46-[NSView(NSLayerKitGlue) drawLayer:inContext:]_block_invoke + 186
  14  AppKit                               0x00007fff8cfc9153 -[NSView(NSLayerKitGlue) _drawViewBackingLayer:inContext:drawingHandler:] + 2297
  15  AppKit                               0x00007fff8cfc8848 -[NSView(NSLayerKitGlue) drawLayer:inContext:] + 108
  16  AppKit                               0x00007fff8d01e57c -[_NSBackingLayerContents drawLayer:inContext:] + 149
  17  QuartzCore                           0x00007fff8768bcc9 -[CALayer drawInContext:] + 115
  18  AppKit                               0x00007fff8d01e0b8 -[_NSTiledLayer drawTile:inContext:] + 654
  19  AppKit                               0x00007fff8d01ddbc -[_NSTiledLayerContents drawLayer:inContext:] + 172
  20  QuartzCore                           0x00007fff8768bcc9 -[CALayer drawInContext:] + 115
  21  AppKit                               0x00007fff8d7f2565 -[NSTileLayer drawInContext:] +     169
  22  QuartzCore                           0x00007fff8768a852 CABackingStoreUpdate_ + 2220
  23  QuartzCore                           0x00007fff87689fa0 ___ZN2CA5Layer8display_Ev_block_invoke + 59
  24  QuartzCore                           0x00007fff87689f5c x_blame_allocations + 84
  25  QuartzCore                           0x00007fff87689a6b _ZN2CA5Layer8display_Ev + 1539
  26  AppKit                               0x00007fff8d01dccf -[NSTileLayer display] + 119
  27  AppKit                               0x00007fff8d01a175 -[_NSTiledLayerContents update:] + 5545
  28  AppKit                               0x00007fff8d0188e8 -[_NSTiledLayer display] + 404
  29  QuartzCore                           0x00007fff8769ce1a _ZL16display_callbackPvS_ + 81
  30  QuartzCore                           0x00007fff8769cd69 _ZN2CA13DispatchGroup8dispatchEb + 69
  31  libdispatch.dylib                    0x00007fff91e9d2ad _dispatch_client_callout + 8
  32  libdispatch.dylib                    0x00007fff91e9f09e _dispatch_root_queue_drain + 326
  33  libdispatch.dylib                    0x00007fff91ea0193 _dispatch_worker_thread2 + 40
  34  libsystem_pthread.dylib              0x00007fff905e9ef8 _pthread_wqthread + 314
  35  libsystem_pthread.dylib              0x00007fff905ecfb9 start_wqthread + 13
  
  Thread 11:
  0   libsystem_kernel.dylib               0x00007fff852b1e6a __workq_kernreturn + 10
  1   libsystem_pthread.dylib              0x00007fff905ecfb9 start_wqthread + 13
  
  Thread 12:
  0   libsystem_kernel.dylib               0x00007fff852b1e6a __workq_kernreturn + 10
  1   libsystem_pthread.dylib              0x00007fff905ecfb9 start_wqthread + 13
  
  Thread 13:
  0   libsystem_kernel.dylib               0x00007fff852b1e6a __workq_kernreturn + 10
  1   libsystem_pthread.dylib              0x00007fff905ecfb9 start_wqthread + 13
  
  Thread 10 crashed with X86-64 Thread State:
     rip: 0x00007fff87f0e097    rbp: 0x000000011ab59d20    rsp: 0x000000011ab59cb8    rax: 0x00007fff76b7c648 
     rbx: 0x0000000000000001    rcx: 0x0000000000000000    rdx: 0x00007fff76b7c648    rdi: 0x00006080006321a0 
     rsi: 0x00007fff8d89320c     r8: 0x00007fff8d85082b     r9: 0x0000000000000032    r10: 0x00007fff8d89320c 
     r11: 0xbadd0dacedb8bead    r12: 0x0000608000232d00    r13: 0x0000000000000002    r14: 0x0000000000000003 
     r15: 0x0000000000000003 rflags: 0x0000000000010246     cs: 0x000000000000002b     fs: 0x0000000000000000 
      gs: 0x000000000e5d0000 
  </code></pre>