title: UIFeedbackGenerator _autoDeactivate crashes iOS 11.2.2
body: <p>I am seeing intermittent crashes with the haptic feedback engine in iOS 11. Unfortunately, I do not have reproducible steps because it seems to be happening randomly.</p>
  
  <p>Here are the exception and stack traces:</p>
  
  <blockquote>
    <p>Exception raised while auto-deactivating &lt;UIImpactFeedbackGenerator: 0x1c850a710: prepared=0> for style 2: force deactivating &lt;UIImpactFeedbackGenerator: 0x1c850a710: prepared=0> with style TurnOn which is not active (activationCount = -1) configuration: &lt;_UIImpactFeedbackGeneratorConfiguration: 0x1c80bc920: isEnabled=1, activationStyle=2, requiredSupportLevel=2> activationCount: -1, styleActivationCount: -1 engines: {( &lt;_UIFeedbackHapticOnlyEngine: 0x1c80db040: state=4, numberOfClients=1, prewarmCount=0, _isSuspended=0> )}</p>
  </blockquote>
  
  <pre>
  # Platform: ios
  # Application: MyApp
  # Version: 3.1.0.4
  # Bundle Identifier: com.company.myApp
  # Issue #: 8845
  # Issue ID: 59ff154761b02d480dd20c28
  # Session ID: 2ec9b043edaa4fcaad12fa480d690e8a_0c4f8c61fbbd11e7924356847afe9799_0_v2
  # Date: 2018-01-17T19:31:00Z
  # OS Version: 11.2.2 (15C202)
  # Device: iPhone 8
  # RAM Free: 20.8%
  # Disk Free: 82.9%
  
  #0. Crashed: com.twitter.crashlytics.ios.exception
  0  MyApp                  0x100d02fb8 CLSProcessRecordAllThreads + 1125008
  1  MyApp                  0x100d02fb8 CLSProcessRecordAllThreads + 1125008
  2  MyApp                  0x100d02e74 CLSProcessRecordAllThreads + 1124684
  3  MyApp                  0x100cf2fa0 CLSHandler + 1059448
  4  MyApp                  0x100d00fd0 __CLSExceptionRecord_block_invoke + 1116840
  5  libdispatch.dylib              0x1853aaa14 _dispatch_client_callout + 16
  6  libdispatch.dylib              0x1853e7d4c _dispatch_queue_barrier_sync_invoke_and_complete + 56
  7  MyApp                  0x100d00a64 CLSExceptionRecord + 1115452
  8  MyApp                  0x100d0088c CLSExceptionRecordNSException + 1114980
  9  MyApp                  0x100d004a0 CLSTerminateHandler() + 1113976
  10 libc++abi.dylib                0x184c6454c std::__terminate(void (*)()) + 16
  11 libc++abi.dylib                0x184c645b8 std::terminate() + 60
  12 libobjc.A.dylib                0x184c7476c _destroyAltHandlerList + 10
  13 libdispatch.dylib              0x1853aaa28 _dispatch_client_callout + 36
  14 libdispatch.dylib              0x1853e7640 _dispatch_continuation_pop$VARIANT$armv81 + 420
  15 libdispatch.dylib              0x1853f0858 _dispatch_source_invoke$VARIANT$armv81 + 528
  16 libdispatch.dylib              0x1853ebb64 _dispatch_main_queue_callback_4CF$VARIANT$armv81 + 684
  17 CoreFoundation                 0x1859d6544 __CFRUNLOOP_IS_SERVICING_THE_MAIN_DISPATCH_QUEUE__ + 12
  18 CoreFoundation                 0x1859d4120 __CFRunLoopRun + 2012
  19 CoreFoundation                 0x1858f3e58 CFRunLoopRunSpecific + 436
  20 GraphicsServices               0x1877a0f84 GSEventRunModal + 100
  21 UIKit                          0x18f04867c UIApplicationMain + 236
  22 MyApp                        0x10049e760 main (main.mm:34)
  23 libdyld.dylib                  0x18541056c start + 4
  
  --
  
  Fatal Exception: NSInternalInconsistencyException
  0  CoreFoundation                 0x185a2e364 __exceptionPreprocess
  1  libobjc.A.dylib                0x184c74528 objc_exception_throw
  2  CoreFoundation                 0x185a2e2ac -[NSException initWithCoder:]
  3  UIKit                          0x18fa29198 -[UIFeedbackGenerator _autoDeactivate]
  4  UIKit                          0x18fa28ec8 __48-[UIFeedbackGenerator _setupAutoDeactivateTimer]_block_invoke
  5  libdispatch.dylib              0x1853aaa14 _dispatch_client_callout
  6  libdispatch.dylib              0x1853e7640 _dispatch_continuation_pop$VARIANT$armv81
  7  libdispatch.dylib              0x1853f0858 _dispatch_source_invoke$VARIANT$armv81
  8  libdispatch.dylib              0x1853ebb64 _dispatch_main_queue_callback_4CF$VARIANT$armv81
  9  CoreFoundation                 0x1859d6544 __CFRUNLOOP_IS_SERVICING_THE_MAIN_DISPATCH_QUEUE__
  10 CoreFoundation                 0x1859d4120 __CFRunLoopRun
  11 CoreFoundation                 0x1858f3e58 CFRunLoopRunSpecific
  12 GraphicsServices               0x1877a0f84 GSEventRunModal
  13 UIKit                          0x18f04867c UIApplicationMain
  14 MyApp                      0x10049e760 main (main.mm:34)
  15 libdyld.dylib                  0x18541056c start
  </pre>
  
  <p>Have others run into this issue?</p>