I am frequently getting a crash log related to UITextfield from our live users. It has been reported on only iOS 13.x and not specific to any iPhone device. There is no origin of error mentioned in the stack trace that can help in debugging.Please refer to stack trace below. textField:shouldChangeCharactersInRange:replacementString is recursively called by our app that leads to crash. It has not been mentioned from where. I have tried to reproduce by different means, but unable to do so. Can anyone draw a guess what may cause this crash?Thanks.Crashed: com.apple.main-threadEXC_BAD_ACCESS KERN_PROTECTION_FAILURE 0x000000016f29fff8Crashed: com.apple.main-thread 0 libsystem_pthread.dylib 0x1a00657b0 ___chkstk_darwin + 64 1 UIFoundation 0x1a38fb050 -[NSGlyphGenerator generateGlyphsForGlyphStorage:desiredNumberOfCharacters:glyphIndex:characterIndex:] + 44 2 UIFoundation 0x1a38fc170 -[NSLayoutManager(NSPrivate) _fillGlyphHoleForCharacterRange:startGlyphIndex:desiredNumberOfCharacters:] + 700 3 UIFoundation 0x1a393e83c _NSFastFillAllGlyphHolesForCharacterRange + 900 4 UIFoundation 0x1a38fc6a8 -[NSLayoutManager glyphRangeForCharacterRange:actualCharacterRange:] + 56 5 UIFoundation 0x1a38ead38 -[NSLayoutManager(NSPrivate) _fillLayoutHoleForCharacterRange:desiredNumberOfLines:isSoft:] + 700 6 UIFoundation 0x1a38ef7b4 -[NSLayoutManager(NSPrivate) _fillLayoutHoleAtIndex:desiredNumberOfLines:] + 196 7 UIFoundation 0x1a38f7240 -[NSLayoutManager(NSPrivate) _markSelfAsDirtyForBackgroundLayout:] + 424 8 UIFoundation 0x1a38f1dd8 -[NSLayoutManager(NSPrivate) _invalidateLayoutForExtendedCharacterRange:isSoft:invalidateUsage:] + 2332 9 UIFoundation 0x1a38f206c -[NSLayoutManager textStorage:edited:range:changeInLength:invalidatedRange:] + 212 10 UIFoundation 0x1a38f1f18 -[NSTextStorage _notifyEdited:range:changeInLength:invalidatedRange:] + 184 11 UIFoundation 0x1a38ef824 -[NSTextStorage endEditing] + 92 12 UIFoundation 0x1a3903a0c -[NSTextStorage coordinateEditing:] + 68 13 UIKitCore 0x1a468541c -[UIFieldEditor _setAttributedTextInRange:replacementText:andSetCaretSelectionAfterText:] + 676 14 UIKitCore 0x1a4684e1c -[UIFieldEditor _setTextInRange:replacementText:andSetCaretSelectionAfterText:] + 204 15 UIKitCore 0x1a4697434 -[UITextField setText:] + 436 16 MyApp-QA 0x100a9e53c -[TextField textField:shouldChangeCharactersInRange:replacementString:] + 311 (TextField.m:311) 17 UIKitCore 0x1a46a3128 -[UITextField _delegateShouldChangeCharactersInTextStorageRange:replacementString:delegateCares:] + 160 18 UIKitCore 0x1a469cee8 -[UITextField keyboardInput:shouldReplaceTextInRange:replacementText:] + 92 19 UIKitCore 0x1a41fc56c -[UIKeyboardImpl acceptAutocorrection:executionContextPassingTIKeyboardCandidate:] + 536 20 UIKitCore 0x1a41ff6d4 -[UIKeyboardImpl acceptPredictiveInput:executionContext:] + 664 21 UIKitCore 0x1a41f5024 -[UIKeyboardImpl inputManagerDidGenerateAutocorrections:executionContext:] + 668 22 UIKitCore 0x1a4221d88 -[UIKeyboardTaskEntry execute:] + 180 23 UIKitCore 0x1a42207b8 -[UIKeyboardTaskQueue continueExecutionOnMainThread] + 316 24 UIKitCore 0x1a4220b20 -[UIKeyboardTaskQueue performTaskOnMainThread:waitUntilDone:] + 320 25 UIKitCore 0x1a41de6a4 -[UIKeyboardImpl generateAutofillCandidateByAddingTask:] + 156 26 UIKitCore 0x1a41f1d18 -[UIKeyboardImpl selectionDidChange:] + 340 27 UIKitCore 0x1a46af9fc __52-[UITextInputController _coordinateSelectionChange:]_block_invoke + 504 28 UIFoundation 0x1a38f4b64 -[NSTextStorage coordinateReading:] + 56 29 UIKitCore 0x1a46af7dc -[UITextInputController _coordinateSelectionChange:] + 148 30 UIKitCore 0x1a46af364 -[UITextInputController _setSelectedTextRange:] + 452 31 UIKitCore 0x1a46af190 -[UITextInputController setSelectedRange:] + 72 32 UIKitCore 0x1a4685498 -[UIFieldEditor _setAttributedTextInRange:replacementText:andSetCaretSelectionAfterText:] + 800 33 UIKitCore 0x1a4684e1c -[UIFieldEditor _setTextInRange:replacementText:andSetCaretSelectionAfterText:] + 204 34 UIKitCore 0x1a4697434 -[UITextField setText:] + 436 35 MyApp-QA 0x100a9e53c -[TextField textField:shouldChangeCharactersInRange:replacementString:] + 311 (TextField.m:311) 36 UIKitCore 0x1a46a3128 -[UITextField _delegateShouldChangeCharactersInTextStorageRange:replacementString:delegateCares:] + 160 37 UIKitCore 0x1a469cee8 -[UITextField keyboardInput:shouldReplaceTextInRange:replacementText:] + 92 38 UIKitCore 0x1a41fc56c -[UIKeyboardImpl acceptAutocorrection:executionContextPassingTIKeyboardCandidate:] + 536 39 UIKitCore 0x1a41ff6d4 -[UIKeyboardImpl acceptPredictiveInput:executionContext:] + 664 40 UIKitCore 0x1a41f5024 -[UIKeyboardImpl inputManagerDidGenerateAutocorrections:executionContext:] + 668 41 UIKitCore 0x1a4221d88 -[UIKeyboardTaskEntry execute:] + 180 42 UIKitCore 0x1a42207b8 -[UIKeyboardTaskQueue continueExecutionOnMainThread] + 316 43 UIKitCore 0x1a4220b20 -[UIKeyboardTaskQueue performTaskOnMainThread:waitUntilDone:] + 320 44 UIKitCore 0x1a41de6a4 -[UIKeyboardImpl generateAutofillCandidateByAddingTask:] + 156 45 UIKitCore 0x1a41f1d18 -[UIKeyboardImpl selectionDidChange:] + 340 46 UIKitCore 0x1a46af9fc __52-[UITextInputController _coordinateSelectionChange:]_block_invoke + 504 47 UIFoundation 0x1a38f4b64 -[NSTextStorage coordinateReading:] + 56 48 UIKitCore 0x1a46af7dc -[UITextInputController _coordinateSelectionChange:] + 148 49 UIKitCore 0x1a46af364 -[UITextInputController _setSelectedTextRange:] + 452 50 UIKitCore 0x1a46af190 -[UITextInputController setSelectedRange:] + 72 51 UIKitCore 0x1a4685498 -[UIFieldEditor _setAttributedTextInRange:replacementText:andSetCaretSelectionAfterText:] + 800 52 UIKitCore 0x1a4684e1c -[UIFieldEditor _setTextInRange:replacementText:andSetCaretSelectionAfterText:] + 204 53 UIKitCore 0x1a4697434 -[UITextField setText:] + 436 54 MyApp-QA 0x100a9e53c -[TextField textField:shouldChangeCharactersInRange:replacementString:] + 311 (TextField.m:311) 55 UIKitCore 0x1a46a3128 -[UITextField _delegateShouldChangeCharactersInTextStorageRange:replacementString:delegateCares:] + 160 56 UIKitCore 0x1a469cee8 -[UITextField keyboardInput:shouldReplaceTextInRange:replacementText:] + 92 57 UIKitCore 0x1a41fc56c -[UIKeyboardImpl acceptAutocorrection:executionContextPassingTIKeyboardCandidate:] + 536 58 UIKitCore 0x1a41ff6d4 -[UIKeyboardImpl acceptPredictiveInput:executionContext:] + 664 59 UIKitCore 0x1a41f5024 -[UIKeyboardImpl inputManagerDidGenerateAutocorrections:executionContext:] + 668 60 UIKitCore 0x1a4221d88 -[UIKeyboardTaskEntry execute:] + 180 61 UIKitCore 0x1a42207b8 -[UIKeyboardTaskQueue continueExecutionOnMainThread] + 316 62 UIKitCore 0x1a4220b20 -[UIKeyboardTaskQueue performTaskOnMainThread:waitUntilDone:] + 320 63 UIKitCore 0x1a41de6a4 -[UIKeyboardImpl generateAutofillCandidateByAddingTask:] + 156 64 UIKitCore 0x1a41f1d18 -[UIKeyboardImpl selectionDidChange:] + 340 65 UIKitCore 0x1a46af9fc __52-[UITextInputController _coordinateSelectionChange:]_block_invoke + 504 66 UIFoundation 0x1a38f4b64 -[NSTextStorage coordinateReading:] + 56 67 UIKitCore 0x1a46af7dc -[UITextInputController _coordinateSelectionChange:] + 148 68 UIKitCore 0x1a46af364 -[UITextInputController _setSelectedTextRange:] + 452 69 UIKitCore 0x1a46af190 -[UITextInputController setSelectedRange:] + 72 70 UIKitCore 0x1a4685498 -[UIFieldEditor _setAttributedTextInRange:replacementText:andSetCaretSelectionAfterText:] + 800 71 UIKitCore 0x1a4684e1c -[UIFieldEditor _setTextInRange:replacementText:andSetCaretSelectionAfterText:] + 204 72 UIKitCore 0x1a4697434 -[UITextField setText:] + 436 73 MyApp-QA 0x100a9e53c -[TextField textField:shouldChangeCharactersInRange:replacementString:] + 311 (TextField.m:311) 74 UIKitCore 0x1a46a3128 -[UITextField _delegateShouldChangeCharactersInTextStorageRange:replacementString:delegateCares:] + 160 75 UIKitCore 0x1a469cee8 -[UITextField keyboardInput:shouldReplaceTextInRange:replacementText:] + 92 76 UIKitCore 0x1a41fc56c -[UIKeyboardImpl acceptAutocorrection:executionContextPassingTIKeyboardCandidate:] + 536 77 UIKitCore 0x1a41ff6d4 -[UIKeyboardImpl acceptPredictiveInput:executionContext:] + 664 78 UIKitCore 0x1a41f5024 -[UIKeyboardImpl inputManagerDidGenerateAutocorrections:executionContext:] + 668 79 UIKitCore 0x1a4221d88 -[UIKeyboardTaskEntry execute:] + 180 80 UIKitCore 0x1a42207b8 -[UIKeyboardTaskQueue continueExecutionOnMainThread] + 316 81 UIKitCore 0x1a4220b20 -[UIKeyboardTaskQueue performTaskOnMainThread:waitUntilDone:] + 320 82 UIKitCore 0x1a41de6a4 -[UIKeyboardImpl generateAutofillCandidateByAddingTask:] + 156 83 UIKitCore 0x1a41f1d18 -[UIKeyboardImpl selectionDidChange:] + 340 84 UIKitCore 0x1a46af9fc __52-[UITextInputController _coordinateSelectionChange:]_block_invoke + 504 85 UIFoundation 0x1a38f4b64 -[NSTextStorage coordinateReading:] + 56 86 UIKitCore 0x1a46af7dc -[UITextInputController _coordinateSelectionChange:] + 148 87 UIKitCore 0x1a46af364 -[UITextInputController _setSelectedTextRange:] + 452 88 UIKitCore 0x1a46af190 -[UITextInputController setSelectedRange:] + 72 89 UIKitCore 0x1a4685498 -[UIFieldEditor _setAttributedTextInRange:replacementText:andSetCaretSelectionAfterText:] + 800 90 UIKitCore 0x1a4684e1c -[UIFieldEditor _setTextInRange:replacementText:andSetCaretSelectionAfterText:] + 204 91 UIKitCore 0x1a4697434 -[UITextField setText:] + 436 92 MyApp-QA 0x100a9e53c -[TextField textField:shouldChangeCharactersInRange:replacementString:] + 311 (TextField.m:311) 93 UIKitCore 0x1a46a3128 -[UITextField _delegateShouldChangeCharactersInTextStorageRange:replacementString:delegateCares:] + 160 94 UIKitCore 0x1a469cee8 -[UITextField keyboardInput:shouldReplaceTextInRange:replacementText:] + 92 95 UIKitCore 0x1a41fc56c -[UIKeyboardImpl acceptAutocorrection:executionContextPassingTIKeyboardCandidate:] + 536 96 UIKitCore 0x1a41ff6d4 -[UIKeyboardImpl acceptPredictiveInput:executionContext:] + 664 97 UIKitCore 0x1a41f5024 -[UIKeyboardImpl inputManagerDidGenerateAutocorrections:executionContext:] + 668 98 UIKitCore 0x1a4221d88 -[UIKeyboardTaskEntry execute:] + 180 99 UIKitCore 0x1a42207b8 -[UIKeyboardTaskQueue continueExecutionOnMainThread] + 316 100 UIKitCore 0x1a4220b20 -[UIKeyboardTaskQueue performTaskOnMainThread:waitUntilDone:] + 320 101 UIKitCore 0x1a41de6a4 -[UIKeyboardImpl generateAutofillCandidateByAddingTask:] + 156 102 UIKitCore 0x1a41f1d18 -[UIKeyboardImpl selectionDidChange:] + 340 103 UIKitCore 0x1a46af9fc __52-[UITextInputController _coordinateSelectionChange:]_block_invoke + 504 104 UIFoundation 0x1a38f4b64 -[NSTextStorage coordinateReading:] + 56 105 UIKitCore 0x1a46af7dc -[UITextInputController _coordinateSelectionChange:] + 148 106 UIKitCore 0x1a46af364 -[UITextInputController _setSelectedTextRange:] + 452 107 UIKitCore 0x1a46af190 -[UITextInputController setSelectedRange:] + 72 108 UIKitCore 0x1a4685498 -[UIFieldEditor _setAttributedTextInRange:replacementText:andSetCaretSelectionAfterText:] + 800 109 UIKitCore 0x1a4684e1c -[UIFieldEditor _setTextInRange:replacementText:andSetCaretSelectionAfterText:] + 204 110 UIKitCore 0x1a4697434 -[UITextField setText:] + 436 111 MyApp-QA 0x100a9e53c -[TextField textField:shouldChangeCharactersInRange:replacementString:] + 311 (TextField.m:311) 112 UIKitCore 0x1a46a3128 -[UITextField _delegateShouldChangeCharactersInTextStorageRange:replacementString:delegateCares:] + 160 113 UIKitCore 0x1a469cee8 -[UITextField keyboardInput:shouldReplaceTextInRange:replacementText:] + 92 114 UIKitCore 0x1a41fc56c -[UIKeyboardImpl acceptAutocorrection:executionContextPassingTIKeyboardCandidate:] + 536 115 UIKitCore 0x1a41ff6d4 -[UIKeyboardImpl acceptPredictiveInput:executionContext:] + 664 116 UIKitCore 0x1a41f5024 -[UIKeyboardImpl inputManagerDidGenerateAutocorrections:executionContext:] + 668 117 UIKitCore 0x1a4221d88 -[UIKeyboardTaskEntry execute:] + 180 118 UIKitCore 0x1a42207b8 -[UIKeyboardTaskQueue continueExecutionOnMainThread] + 316 119 UIKitCore 0x1a4220b20 -[UIKeyboardTaskQueue performTaskOnMainThread:waitUntilDone:] + 320 120 UIKitCore 0x1a41de6a4 -[UIKeyboardImpl generateAutofillCandidateByAddingTask:] + 156 121 UIKitCore 0x1a41f1d18 -[UIKeyboardImpl selectionDidChange:] + 340 122 UIKitCore 0x1a46af9fc __52-[UITextInputController _coordinateSelectionChange:]_block_invoke + 504 123 UIFoundation 0x1a38f4b64 -[NSTextStorage coordinateReading:] + 56 124 UIKitCore 0x1a46af7dc -[UITextInputController _coordinateSelectionChange:] + 148 125 UIKitCore 0x1a46af364 -[UITextInputController _setSelectedTextRange:] + 452 126 UIKitCore 0x1a46af190 -[UITextInputController setSelectedRange:] + 72 127 UIKitCore 0x1a4685498 -[UIFieldEditor _setAttributedTextInRange:replacementText:andSetCaretSelectionAfterText:] + 800 128 UIKitCore 0x1a4684e1c -[UIFieldEditor _setTextInRange:replacementText:andSetCaretSelectionAfterText:] + 204 129 UIKitCore 0x1a4697434 -[UITextField setText:] + 436 130 MyApp-QA 0x100a9e53c -[TextField textField:shouldChangeCharactersInRange:replacementString:] + 311 (TextField.m:311) 131 UIKitCore 0x1a46a3128 -[UITextField _delegateShouldChangeCharactersInTextStorageRange:replacementString:delegateCares:] + 160 132 UIKitCore 0x1a469cee8 -[UITextField keyboardInput:shouldReplaceTextInRange:replacementText:] + 92 133 UIKitCore 0x1a41fc56c -[UIKeyboardImpl acceptAutocorrection:executionContextPassingTIKeyboardCandidate:] + 536 134 UIKitCore 0x1a41ff6d4 -[UIKeyboardImpl acceptPredictiveInput:executionContext:] + 664 135 UIKitCore 0x1a41f5024 -[UIKeyboardImpl inputManagerDidGenerateAutocorrections:executionContext:] + 668 136 UIKitCore 0x1a4221d88 -[UIKeyboardTaskEntry execute:] + 180 137 UIKitCore 0x1a42207b8 -[UIKeyboardTaskQueue continueExecutionOnMainThread] + 316 138 UIKitCore 0x1a4220b20 -[UIKeyboardTaskQueue performTaskOnMainThread:waitUntilDone:] + 320 139 UIKitCore 0x1a41de6a4 -[UIKeyboardImpl generateAutofillCandidateByAddingTask:] + 156 140 UIKitCore 0x1a41f1d18 -[UIKeyboardImpl selectionDidChange:] + 340 141 UIKitCore 0x1a46af9fc __52-[UITextInputController _coordinateSelectionChange:]_block_invoke + 504 142 UIFoundation 0x1a38f4b64 -[NSTextStorage coordinateReading:] + 56 143 UIKitCore 0x1a46af7dc -[UITextInputController _coordinateSelectionChange:] + 148 144 UIKitCore 0x1a46af364 -[UITextInputController _setSelectedTextRange:] + 452 145 UIKitCore 0x1a46af190 -[UITextInputController setSelectedRange:] + 72 146 UIKitCore 0x1a4685498 -[UIFieldEditor _setAttributedTextInRange:replacementText:andSetCaretSelectionAfterText:] + 800 147 UIKitCore 0x1a4684e1c -[UIFieldEditor _setTextInRange:replacementText:andSetCaretSelectionAfterText:] + 204 148 UIKitCore 0x1a4697434 -[UITextField setText:] + 436 149 MyApp-QA 0x100a9e53c -[TextField textField:shouldChangeCharactersInRange:replacementString:] + 311 (TextField.m:311) 150 UIKitCore 0x1a46a3128 -[UITextField _delegateShouldChangeCharactersInTextStorageRange:replacementString:delegateCares:] + 160 151 UIKitCore 0x1a469cee8 -[UITextField keyboardInput:shouldReplaceTextInRange:replacementText:] + 92 152 UIKitCore 0x1a41fc56c -[UIKeyboardImpl acceptAutocorrection:executionContextPassingTIKeyboardCandidate:] + 536 153 UIKitCore 0x1a41ff6d4 -[UIKeyboardImpl acceptPredictiveInput:executionContext:] + 664 154 UIKitCore 0x1a41f5024 -[UIKeyboardImpl inputManagerDidGenerateAutocorrections:executionContext:] + 668 155 UIKitCore 0x1a4221d88 -[UIKeyboardTaskEntry execute:] + 180 156 UIKitCore 0x1a42207b8 -[UIKeyboardTaskQueue continueExecutionOnMainThread] + 316 157 UIKitCore 0x1a4220b20 -[UIKeyboardTaskQueue performTaskOnMainThread:waitUntilDone:] + 320 158 UIKitCore 0x1a41de6a4 -[UIKeyboardImpl generateAutofillCandidateByAddingTask:] + 156 159 UIKitCore 0x1a41f1d18 -[UIKeyboardImpl selectionDidChange:] + 340 160 UIKitCore 0x1a46af9fc __52-[UITextInputController _coordinateSelectionChange:]_block_invoke + 504