title: Crash on __pthread_kill
body: <p>Got the crash report below, but have no clue why it would be happening and how to fix it.</p>
  
  <blockquote>
    <p>SIGABRT ABORT at 0x000000019aa3258c</p>
    
    <p>libsystem_kernel.dylib
    __pthread_kill</p>
  </blockquote>
  
  <pre><code>Thread : Crashed: com.apple.main-thread
  0  libsystem_kernel.dylib         0x000000019aa3258c __pthread_kill + 8
  1  libsystem_pthread.dylib        0x000000019aab516c pthread_kill + 104
  2  libsystem_c.dylib              0x000000019a9c6808 abort + 112
  3  libc++abi.dylib                0x0000000199bec994 __cxa_bad_cast
  4  libc++abi.dylib                0x0000000199c07184 std::__terminate(void (*)()) + 44
  5  libc++abi.dylib                0x0000000199c06d3c __cxa_rethrow + 144
  6  libobjc.A.dylib                0x000000019a3443a8 objc_exception_rethrow + 44
  7  CoreFoundation                 0x000000018dd3d74c CFRunLoopRunSpecific + 576
  8  GraphicsServices               0x0000000193a21c0c GSEventRunModal + 168
  9  UIKit                          0x0000000190e6efdc UIApplicationMain + 1156
  10 *************                  0x00000001000a5c80 main (main.m:17)
  11 libdyld.dylib                  0x000000019a937aa0 start + 4
  </code></pre>