Decipher the iOS crashlog. The program crashes at layoutIfNeeded - ios

Question

I've got crash logs for my app from App Store. I'm not able to reproduce the crash and having a hard time deciphering it.
Following is the log -
Incident Identifier: AEF0FFDD-77E4-460F-97E4-B97A32EAE36D
CrashReporter Key: 78177aeeda1175c67f4467d02c023a2a165d1a01
Hardware Model: iPhone7,1
Process: Visits [4558]
Path: /private/var/containers/Bundle/Application/81AC75BC-433C-43E7-887D-8FC6BF5B5703/Visits.app/Visits
Identifier: com.x.y
Version: 1.1.1 (1.1.1)
Code Type: ARM-64 (Native)
Role: Foreground
Parent Process: launchd [1]
Coalition: com.x.y [1143]
Date/Time: 2018-07-20 22:30:36.6608 +0530
Launch Time: 2018-07-20 22:30:35.9017 +0530
OS Version: iPhone OS 11.4.1 (15G77)
Baseband Version: 6.80.00
Report Version: 104
Exception Type: EXC_CRASH (SIGABRT)
Exception Codes: 0x0000000000000000, 0x0000000000000000
Exception Note: EXC_CORPSE_NOTIFY
Triggered by Thread: 0
Last Exception Backtrace:
0 CoreFoundation 0x184136d8c __exceptionPreprocess + 228 (NSException.m:166)
1 libobjc.A.dylib 0x1832f05ec objc_exception_throw + 56 (objc-exception.mm:521)
2 CoreFoundation 0x1840cfd80 -[__NSSingleObjectArrayI objectAtIndex:] + 128 (NSSingleObjectArray.m:16)
3 UIKit 0x18e6b0aa8 -[UITableViewDataSource tableView:cellForRowAtIndexPath:] + 172 (UITableViewDataSource.m:170)
4 UIKit 0x18e3c90f4 -[UITableViewController tableView:cellForRowAtIndexPath:] + 68 (UITableViewController.m:441)
5 UIKit 0x18de130cc -[UITableView _createPreparedCellForGlobalRow:withIndexPath:willDisplay:] + 668 (UITableView.m:13463)
6 UIKit 0x18de12d84 -[UITableView _createPreparedCellForGlobalRow:willDisplay:] + 80 (UITableView.m:13514)
7 UIKit 0x18de11aa0 -[UITableView _updateVisibleCellsNow:isRecursive:] + 2280 (UITableView.m:2599)
8 UIKit 0x18de0d5ec -[UITableView layoutSubviews] + 140 (UITableView.m:8565)
9 UIKit 0x18dd4a6f4 -[UIView(CALayerDelegate) layoutSublayersOfLayer:] + 1420 (UIView.m:15239)
10 QuartzCore 0x1882bfe54 -[CALayer layoutSublayers] + 184 (CALayer.mm:9357)
11 QuartzCore 0x1882c3fe4 CA::Layer::layout_if_needed(CA::Transaction*) + 324 (CALayer.mm:9237)
12 UIKit 0x18dd62bf4 -[UIView(Hierarchy) layoutBelowIfNeeded] + 548 (UIView.m:10438)
13 Visits 0x1007a8300 MainViewController.initialSetupForScreen() + 804 (MainViewController.swift:217)
14 Visits 0x1007a7ea4 MainViewController.viewDidLoad() + 924 (MainViewController.swift:175)
15 Visits 0x1007a8838 #objc MainViewController.viewDidLoad() + 28
16 UIKit 0x18dd51e64 -[UIViewController loadViewIfRequired] + 1020 (UIViewController.m:3192)
17 UIKit 0x18dd51a50 -[UIViewController view] + 28 (UIViewController.m:3214)
18 UIKit 0x18dd42ce4 -[UIWindow addRootViewControllerViewIfPossible] + 136 (UIWindow.m:1358)
19 UIKit 0x18dd41b18 -[UIWindow _setHidden:forced:] + 272 (UIWindow.m:1455)
20 UIKit 0x18ddcf62c -[UIWindow makeKeyAndVisible] + 48 (UIWindow.m:4883)
21 UIKit 0x18dd45274 -[UIApplication _callInitializationDelegatesForMainScene:transitionContext:] + 3660 (UIApplication.m:2210)
22 UIKit 0x18dd125e0 -[UIApplication _runWithMainScene:transitionContext:completion:] + 1680 (UIApplication.m:3491)
23 UIKit 0x18e342b1c __111-[__UICanvasLifecycleMonitor_Compatability _scheduleFirstCommitForScene:transition:firstActivation:completion:]_block_invoke + 784 (_UICanvasLifecycleMonitor.m:175)
24 UIKit 0x18dd11dd0 +[_UICanvas _enqueuePostSettingUpdateTransactionBlock:] + 160 (_UICanvas.m:591)
25 UIKit 0x18dd11c6c -[__UICanvasLifecycleMonitor_Compatability _scheduleFirstCommitForScene:transition:firstActivation:completion:] + 240 (_UICanvasLifecycleMonitor.m:153)
26 UIKit 0x18dd10afc -[__UICanvasLifecycleMonitor_Compatability activateEventsOnly:withContext:completion:] + 724 (_UICanvasLifecycleMonitor.m:229)
27 UIKit 0x18e9a684c __82-[_UIApplicationCanvas _transitionLifecycleStateWithTransitionContext:completion:]_block_invoke + 296 (_UIApplicationCanvas.m:0)
28 UIKit 0x18dd101ec -[_UIApplicationCanvas _transitionLifecycleStateWithTransitionContext:completion:] + 432 (_UIApplicationCanvas.m:156)
29 UIKit 0x18e78bac8 __125-[_UICanvasLifecycleSettingsDiffAction performActionsForCanvas:withUpdatedScene:settingsDiff:fromSettings:transitionContext:]_block_invoke + 220 (_UICanvasLifecycleSettingsDiffAction.m:211)
30 UIKit 0x18e8d9bf8 _performActionsWithDelayForTransitionContext + 112 (_UICanvasSettingsDiffAction.m:34)
31 UIKit 0x18dd0fc0c -[_UICanvasLifecycleSettingsDiffAction performActionsForCanvas:withUpdatedScene:settingsDiff:fromSettings:transitionContext:] + 248 (_UICanvasLifecycleSettingsDiffAction.m:182)
32 UIKit 0x18dd0f5a8 -[_UICanvas scene:didUpdateWithDiff:transitionContext:completion:] + 368 (_UICanvas.m:517)
33 UIKit 0x18dd0c5e0 -[UIApplication workspace:didCreateScene:withTransitionContext:completion:] + 540 (UIApplication.m:3109)
34 UIKit 0x18dd0c330 -[UIApplicationSceneClientAgent scene:didInitializeWithEvent:completion:] + 364 (UIApplicationSceneClientAgent.m:41)
35 FrontBoardServices 0x186938470 -[FBSSceneImpl _didCreateWithTransitionContext:completion:] + 364 (FBSSceneImpl.m:460)
36 FrontBoardServices 0x186940d6c __56-[FBSWorkspace client:handleCreateScene:withCompletion:]_block_invoke_2 + 224 (FBSWorkspace.m:606)
37 libdispatch.dylib 0x183a28a60 _dispatch_client_callout + 16 (object.m:507)
38 libdispatch.dylib 0x183a30170 _dispatch_block_invoke_direct$VARIANT$mp + 224 (queue.c:3018)
39 FrontBoardServices 0x18696c878 __FBSSERIALQUEUE_IS_CALLING_OUT_TO_A_BLOCK__ + 36 (FBSSerialQueue.m:164)
40 FrontBoardServices 0x18696c51c -[FBSSerialQueue _performNext] + 404 (FBSSerialQueue.m:196)
41 FrontBoardServices 0x18696cab8 -[FBSSerialQueue _performNextFromRunLoopSource] + 56 (FBSSerialQueue.m:232)
42 CoreFoundation 0x1840df404 __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION__ + 24 (CFRunLoop.c:1982)
43 CoreFoundation 0x1840dec2c __CFRunLoopDoSources0 + 276 (CFRunLoop.c:2017)
44 CoreFoundation 0x1840dc79c __CFRunLoopRun + 1204 (CFRunLoop.c:2920)
45 CoreFoundation 0x183ffcda8 CFRunLoopRunSpecific + 552 (CFRunLoop.c:3245)
46 GraphicsServices 0x185fe2020 GSEventRunModal + 100 (GSEvent.c:2245)
47 UIKit 0x18e01c758 UIApplicationMain + 236 (UIApplication.m:3965)
48 Visits 0x1007a589c main + 56 (Location+CoreDataClass.swift:15)
49 libdyld.dylib 0x183a8dfc0 start + 4
Thread 0 name:
Thread 0 Crashed:
0 libsystem_kernel.dylib 0x0000000183bbd2e0 __pthread_kill + 8
1 libsystem_pthread.dylib 0x0000000183d5e288 pthread_kill$VARIANT$mp + 376 (pthread.c:1484)
2 libsystem_c.dylib 0x0000000183b2bd0c abort + 140 (abort.c:91)
3 libc++abi.dylib 0x00000001832c72c8 abort_message + 132 (abort_message.cpp:75)
4 libc++abi.dylib 0x00000001832c7470 default_terminate_handler() + 304 (cxa_default_handlers.cpp:68)
5 libobjc.A.dylib 0x00000001832f08d4 _objc_terminate() + 124 (objc-exception.mm:657)
6 libc++abi.dylib 0x00000001832e137c std::__terminate(void (*)()) + 16 (cxa_handlers.cpp:66)
7 libc++abi.dylib 0x00000001832e1400 std::terminate() + 84 (cxa_handlers.cpp:97)
8 libdispatch.dylib 0x0000000183a28a74 _dispatch_client_callout + 36 (object.m:510)
9 libdispatch.dylib 0x0000000183a30170 _dispatch_block_invoke_direct$VARIANT$mp + 224 (queue.c:3018)
10 FrontBoardServices 0x000000018696c878 __FBSSERIALQUEUE_IS_CALLING_OUT_TO_A_BLOCK__ + 36 (FBSSerialQueue.m:164)
11 FrontBoardServices 0x000000018696c51c -[FBSSerialQueue _performNext] + 404 (FBSSerialQueue.m:196)
12 FrontBoardServices 0x000000018696cab8 -[FBSSerialQueue _performNextFromRunLoopSource] + 56 (FBSSerialQueue.m:232)
13 CoreFoundation 0x00000001840df404 __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION__ + 24 (CFRunLoop.c:1982)
14 CoreFoundation 0x00000001840dec2c __CFRunLoopDoSources0 + 276 (CFRunLoop.c:2017)
15 CoreFoundation 0x00000001840dc79c __CFRunLoopRun + 1204 (CFRunLoop.c:2920)
16 CoreFoundation 0x0000000183ffcda8 CFRunLoopRunSpecific + 552 (CFRunLoop.c:3245)
17 GraphicsServices 0x0000000185fe2020 GSEventRunModal + 100 (GSEvent.c:2245)
18 UIKit 0x000000018e01c758 UIApplicationMain + 236 (UIApplication.m:3965)
19 Visits 0x00000001007a589c main + 56 (Location+CoreDataClass.swift:15)
20 libdyld.dylib 0x0000000183a8dfc0 start + 4
Following is the code snippet where the program crashes. The crash happens at the self.view.layoutIfNeeded().
func initialSetupForScreen(){
let screenHeight = UIScreen.main.bounds.height
let statusBarHeight = UIApplication.shared.statusBarFrame.height
fullyOpenSheetTop = -(screenHeight - (statusBarHeight * 2))
partiallyOpenSheetTop = -((screenHeight * 0.50) - titleBarHeight)
closedSheetTop = -titleBarHeight
notVisibleSheetTop = 40 //(+40 for iphone X)
fullyOrPartiallyThreshold = (fullyOpenSheetTop + partiallyOpenSheetTop)/2
partiallyOrClosedThreshold = (partiallyOpenSheetTop + closedSheetTop)/2
// set primary & secondary sheet height //(+40 for iphone X) (-40 fixed for iphone X)
primarySheetViewHeightConstraint.constant = -fullyOpenSheetTop
secondarySheetViewHeightConstraint.constant = -fullyOpenSheetTop
// primary sheet is set to fully open state
primarySheetViewTopConstraint.constant = fullyOpenSheetTop
primarySheetCurrentState = .fullyOpen
// secondary sheet is set to not visible state
secondarySheetViewTopConstraint.constant = notVisibleSheetTop
secondarySheetCurrentState = .notVisible
// settings View move it out of screen
settingsViewTopConstraint.constant = notVisibleSheetTop
primarySheetController.configurePrimarySheetContentView()
self.view.layoutIfNeeded()
}
Earlier, I was calling this function inside my viewDidLoad. I thought it was too early to call layoutIfNeeded inside viewDidLoad. So I moved the function to viewWillAppear. However, the crashes still seem to be happening . What am I missing/overseeing?
The crash is happening across very few devices and I'm not able to reproduce it.