title: In iOS, what caused this crash?
body: <p>I got a crash in my iOS app, but their has only a few messages, some like this.</p>
  
  <pre><code>Application received signal SIGABRT
  (null)
  (
  0   CoreFoundation                      0x359c68a7 __exceptionPreprocess + 186
  1   libobjc.A.dylib                     0x37d6d259 objc_exception_throw + 32
  2   CoreFoundation                      0x359c6789 +[NSException raise:format:] + 0
  3   CoreFoundation                      0x359c67ab +[NSException raise:format:] + 34
  4   myapp                               0x00241bf9 _ZNSt11_Deque_baseIsSaIsEE15_M_create_nodesEPPsS3_ + 1432772
  5   libsystem_c.dylib                   0x32dd27e3 _sigtramp + 38
  6   libsystem_c.dylib                   0x32dc820f pthread_kill + 54
  7   libsystem_c.dylib                   0x32dc129f abort + 94
  8   libc++abi.dylib                     0x35d7ef6b abort_message + 46
  9   libc++abi.dylib                     0x35d7c3f1 _ZL19safe_handler_callerPFvvE + 120
  10  libc++abi.dylib                     0x35d7c451 _ZdlPv + 0
  11  libc++abi.dylib                     0x35d7d825 __cxa_current_exception_type + 0
  12  libobjc.A.dylib                     0x37d6d2a9 objc_exception_rethrow + 12
  13  CoreFoundation                      0x3591c50d CFRunLoopRunSpecific + 404
  14  CoreFoundation                      0x3591c36d CFRunLoopRunInMode + 104
  15  GraphicsServices                    0x375b8439 GSEventRunModal + 136
  16  UIKit                               0x33428cd5 UIApplicationMain + 1080
  17  myapp                               0x000d4293 _mh_execute_header + 41619
  18  myapp                               0x000ccd20 _mh_execute_header + 11552
  )
  </code></pre>
  
  <p>I can't find what caused this crash, but it is the most frequently appears in my app. I am very anxious, does any one know something about it? Thanks a lot.</p>