What is the root cause of this crashes CTI-IOS-KE

EXC_BAD_ACCESS

applicationFrameworkContext > currentThread > DRHT > tConstraint > threadDictionary >

Attempted to dereference garbage pointer 0xa3528eed0.

objc_msgSend

• UIFoundation0x1bcd75adc

  +[NSStringDrawingTextStorageSettings threadSpecificStringDrawingTextStorageSettings:]

• UIFoundation0x19d3f4fb4

  +[NSString(NSStringDrawing) typesetterBehavior]

• UIFoundation0x1bcddd398

  __NSStringDrawingEngine

• UIFoundation0x22adb2428

  -[NSString(NSExtendedStringDrawing) drawWithRect:options:attributes:context:]

• UIKitCore0x24d146188

  -[UILabel _drawTextInRect:baselineCalculationOnly:]

• UIKitCore0x24d144a58

  -[UILabel drawTextInRect:]

• UIKitCore0x1bf2bd4e0

  -[UIView(CALayerDelegate) drawLayer:inContext:]

• QuartzCore0x197294d90

  -[CALayer drawInContext:]

• QuartzCore0x197179970

  CABackingStoreUpdate_

• QuartzCore0x1859bc89c

  ___ZN2CA5Layer8display_Ev_block_invoke

• QuartzCore0x1859b5654

  -[CALayer _display]

• QuartzCore0x18591e15c

  CA::Context::commit_transaction

• QuartzCore0x1a0bf0104

  CA::Transaction::commit

• QuartzCore0x1c03ed284

  CA::Transaction::release_thread

• libsystem_pthread0x1ba02f4b0

  _pthread_tsd_cleanup

• libsystem_pthread0x1ba02c900

  _pthread_exit

• libsystem_pthread0x19c3ed504

  _pthread_wqthread_exit

• libsystem_pthread0x19c3ed148

  _pthread_wqthread
  

Thanks in advance, for any question please let me know.