title: Crashlytics Swift: Get fatalError() message to the crashlog
body: <p>I have a number of <code>fatalError("Descriptive Error")</code> lines in my app. I'd like to find which line has actually triggered the error.</p>
  
  <p>However, I can't get such an information with Crashlytics. Here's what I got:</p>
  
  <pre><code>#0. Crashed: com.apple.main-thread
  0  libswiftCore.dylib             0x10173cd24 specialized _fatalErrorMessage(_:_:file:line:flags:) + 128
  1  libswiftCore.dylib             0x101561118 _ArrayBuffer._checkInoutAndNativeTypeCheckedBounds(_:wasNativeTypeChecked:) + 240
  2  libswiftCore.dylib             0x10157b318 Array.subscript.getter + 112
  3  AppName                       0x10097d520 ClassName3.select(_:) (ClassName3.swift:61)
  4  AppName                       0x1008ee03c ClassName2.init(_:) (ClassName2.swift:28)
  5  AppName                       0x1008edca0 ClassName2.__allocating_init(_:) (ClassName2.swift:24)
  6  AppName                       0x1008603c4 ClassName4.makeController() (ClassName4.swift:19)
  7  AppName                       0x1008d6c88 ClassName.ClassName6(_:didSelect:) (ClassName.swift:108)
  8  AppName                       0x1008d6e04 protocol witness for ClassName6Delegate.ClassName6(_:didSelect:) in conformance ClassName (&lt;compiler-generated&gt;)
  9  AppName                       0x100855de0 ClassName6.text(card:) (ClassName6Item.swift:71)
  10 AppName                       0x100855f04 protocol witness for ClassName5.text(card:) in conformance ClassName6 (&lt;compiler-generated&gt;)
  11 AppName                       0x1007da8f4 ClassCell.buttonDidTap(_:) (ClassCell.swift:48)
  12 AppName                       0x1007da958 @objc ClassCell.buttonDidTap(_:) (&lt;compiler-generated&gt;)
  13 UIKit                          0x18d4826c8 -[UIApplication sendAction:to:from:forEvent:] + 96
  14 UIKit                          0x18d5a38a4 -[UIControl sendAction:to:forEvent:] + 80
  15 UIKit                          0x18d48877c -[UIControl _sendActionsForEvents:withEvent:] + 440
  16 UIKit                          0x18d5be1dc -[UIControl touchesEnded:withEvent:] + 572
  17 UIKit                          0x18da63dd8 _UIGestureEnvironmentSortAndSendDelayedTouches + 4340
  18 UIKit                          0x18da60b50 _UIGestureEnvironmentUpdate + 1236
  19 UIKit                          0x18d4fb540 -[UIGestureEnvironment _deliverEvent:toGestureRecognizers:usingBlock:] + 404
  20 UIKit                          0x18d4fb078 -[UIGestureEnvironment _updateGesturesForEvent:window:] + 276
  21 UIKit                          0x18d4fa8dc -[UIWindow sendEvent:] + 3132
  22 UIKit                          0x18d4f9238 -[UIApplication sendEvent:] + 340
  23 UIKit                          0x18dcdac0c __dispatchPreprocessedEventFromEventQueue + 2340
  24 UIKit                          0x18dcdd1b8 __handleEventQueueInternal + 4744
  25 UIKit                          0x18dcd6258 __handleHIDEventFetcherDrain + 152
  26 CoreFoundation                 0x1836fb404 __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION__ + 24
  27 CoreFoundation                 0x1836fac2c __CFRunLoopDoSources0 + 276
  28 CoreFoundation                 0x1836f879c __CFRunLoopRun + 1204
  29 CoreFoundation                 0x183618da8 CFRunLoopRunSpecific + 552
  30 GraphicsServices               0x1855fb020 GSEventRunModal + 100
  31 UIKit                          0x18d5f978c UIApplicationMain + 236
  32 AppName                       0x1008925c0 main (AppDelegate.swift:13)
  33 libdyld.dylib                  0x1830a9fc0 start + 
  </code></pre>
  
  <p>4</p>
  
  <p>Is there any way I can retrieve the message in <code>specialized _fatalErrorMessage(_:_:file:line:flags:) + 128</code> ?</p>