EXC_BAD_ACCESS KERN_INVALID_ADDRESS 0x0000000000000*** - ios

Question

During few days I am seeing a firebase crash analytic issue (given below) in my console. I am surfing a log but didn't get any solution. I am not sure the crush Mocking line-1 and line-2 (inside the self.addTransferOperation() function). If it is 'addOperation' related issue (line-2), what will its solution then. How it is possible to become the operation (transferOperation) nil. Advance thanks for your help.
line-1:
_ = self.addTransferOperation(device: device, deviceIndex:index, dataTransferCategory:OMVitalDataTransferCategory.bloodPressure)
Line-2:
func addTransferOperation(device: ConnectedDevice, deviceIndex:Int, dataTransferCategory:OMVitalDataTransferCategory = OMVitalDataTransferCategory.all) -> ConnectivityTransferOperation {
let transferOperation = ConnectivityTransferOperation()
// transferOperation.isUserNotify = device == sortedDeviceList.last ? notifyUser : false
let connectedDevice = ConnectedDevice(value : device)
transferOperation.device = ConnectedDevice(value : device)
transferOperation.transferDataType = dataTransferCategory
transferOperation.completionBlock = {
LogManager.shared.addLog(logString: "completion of transfer operation",localName: connectedDevice.deviceLocalName, uuid: connectedDevice.uuid)
// Remove first item
if !self.pendingOperations.syncInProgress.isEmpty {
self.pendingOperations.syncInProgress.removeAll(where: {$0 == transferOperation})
}
// Empty queue
if self.pendingOperations.syncInProgress.isEmpty {
// update autosync timer if Manual sync
if (self.isManualSync) {
self.updateSyncTimer()
}
}
// Reset bluetooth state
self.resetBluetoothState()
DispatchQueue.main.async {
// Set error from transfer operation and set flag to check if it happened in transfer operation
let transferOperationDetails: [String : Any] = [ConnectivityConfiguration.error: transferOperation.error,
ConnectivityConfiguration.isTransferOperation:true]
// post notification for stop data transfer with transfer error operation object
NotificationCenter.default.post(name: .dataTransferStop,
object: transferOperationDetails)
}
}
LogManager.shared.addLog(logString: "Add transfer operation for device \(device.displayName)",localName: connectedDevice.deviceLocalName, uuid: connectedDevice.uuid)
// Add operation and start
self.pendingOperations.syncInProgress.append(transferOperation)
if deviceIndex > 0 {
// add dependency
transferOperation.addDependency(self.pendingOperations.syncInProgress[deviceIndex-1])
}
self.pendingOperations.syncQueue.addOperation(transferOperation)
return transferOperation
}
Crash:
Crashed: com.apple.main-thread
0 Foundation 0x114ea8 ____addOperations_block_invoke.567 + 680
1 Foundation 0x113858 __addOperations + 1288
2 GrandApp 0x7bd3d8 ConnectivityManager.addTransferOperation(device:deviceIndex:dataTransferCategory:) + 2411 (ConnectivityManager.swift:2411)
3 GrandApp 0x7bc3f0 ConnectivityManager.transferOperation(withDevices:notifyUser:isManualSync:) + 4313269232 (<compiler-generated>:4313269232)
4 GrandApp 0x7a6770 ConnectivityManager.startTransferOperation(notifyUser:device:syncAllData:isBeaconFlow:) + 4313180016 (<compiler-generated>:4313180016)
5 GrandApp 0x6c4aa4 closure #1 in DashboardViewController.refreshAction() + 1096 (DashboardViewController.swift:1096)
6 GrandApp 0x7cc37c specialized ConnectivityManager.isSyncing(withStop:completion:) + 4313334652 (<compiler-generated>:4313334652)
7 GrandApp 0x6c4218 DashboardViewController.refreshAction() + 4312252952 (<compiler-generated>:4312252952)
8 GrandApp 0x6c4aec #objc DashboardViewController.refreshAction() + 4312255212 (<compiler-generated>:4312255212)
9 UIKitCore 0x8be300 -[UIApplication sendAction:to:from:forEvent:] + 96
10 UIKitCore 0x367424 -[UIControl sendAction:to:forEvent:] + 80
11 UIKitCore 0x367744 -[UIControl _sendActionsForEvents:withEvent:] + 440
12 UIKitCore 0x3667b0 -[UIControl touchesEnded:withEvent:] + 568
13 UIKitCore 0x8f55c4 -[UIWindow _sendTouchesForEvent:] + 2108
14 UIKitCore 0x8f67ec -[UIWindow sendEvent:] + 3140
15 UIKitCore 0x8d685c -[UIApplication sendEvent:] + 340
16 UIKitCore 0x99c9d4 __dispatchPreprocessedEventFromEventQueue + 1768
17 UIKitCore 0x99f100 __handleEventQueueInternal + 4828
18 UIKitCore 0x998330 __handleHIDEventFetcherDrain + 15
19 CoreFoundation 0xaaf1c CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION + 24
20 CoreFoundation 0xaae9c __CFRunLoopDoSource0 + 88
21 CoreFoundation 0xaa784 __CFRunLoopDoSources0 + 176
22 CoreFoundation 0xa56c0 __CFRunLoopRun + 1004
23 CoreFoundation 0xa4fb4 CFRunLoopRunSpecific + 436
24 GraphicsServices 0xa79c GSEventRunModal + 104
25 UIKitCore 0x8bcc38 UIApplicationMain + 212
26 GrandApp 0x1db0c main + 19 (AppDelegate.swift:19)
27 libdyld.dylib 0x18e0 start + 4
ConnectivityTransferOperation.swift
import UIKit
import OMConnectivityLibrary
/// Transfer operation for connectivity
class ConnectivityTransferOperation : ConnectivityOperation {
override func main() {
guard isCancelled == false else {
finish(true)
return
}
self.executing(true)
}
override func end() {
// Super call
super.end()
}
}
ConnectivityOperation.swift
import UIKit
import OMConnectivityLibrary
class ConnectivityOperation: Operation {
/// Making operation queue async
override var isAsynchronous: Bool {
get {
return true
}
}
private var _executing = false {
willSet {
willChangeValue(forKey: "isExecuting")
}
didSet {
didChangeValue(forKey: "isExecuting")
}
}
private var _finished = false {
willSet {
willChangeValue(forKey: "isFinished")
}
didSet {
didChangeValue(forKey: "isFinished")
}
}
override var isExecuting: Bool {
return _executing
}
override var isFinished: Bool {
return _finished
}
func executing(_ executing: Bool) {
_executing = executing
}
func finish(_ finished: Bool) {
_finished = finished
}
func end() {
self.finish(true)
self.executing(false)
}
}