For each stack trace posted, can you expand the full stack trace to show the hidden symbols (click on the triangle icons on the left side of the stack trace)?

Do you know which iOS versions caused the crashes?

ios 11.2.5 (15D60) iPhone 7 Plus
ios 11.3.1 (15E302) iPhone 7

11.3.1 (15E302) iPhone 7
11.2.5 (15D60) iPhone 7 Plus
11.3.1 (15E302) 7 Plus

11.2.1 (15C153) iPhone 7
11.3.1 (15E302) iPhone X
11.3.1 (15E302) iPhone 6

11.2.5 (15D60) iPhone 7 Plus
11.3.0 (15E216) iPhone 7

11.2.5 (15D60) iPhone 7 Plus

11.2.5 (15D60) iPhone 7 Plus

The crashes here are all in methods that shouldn't crash (like +[NSDate date]) or in retain/release. They may not be issues related to Firebase, and we likely won't be able to debug them without repro.

@Lingyj can you try updating to Firebase 5 and seeing if these are still present?

I catght it just now but only once. I opened the Zombie Objects and run the project, the crash occured.

I guess the crash [FIRASearchAdReporter scheduleSearchAdReport] because of nonatomic. nonatomic is not thread-safe. In the other thread, the method is executing and coursed the crash. You can read this link.

I think the self in the async block might have been deallocated. We should check whether self has been nil in the async call block. Can someone fix the FIRMutableDictionary and FIRNetwork? @morganchen12 @ryanwilson

Regarding the screenshot of FIRAMonitor, please upgrade to the latest version and use the flag UseCFPreferencesLibrary=YES in the Info.plist? Please let us know whether you see the crash again. Thanks

@Lingyj are you able to capture the same zombie crash with an exception breakpoint enabled (or are you able to share the exception message with the backtrace)? The stack traces provided end in __dealloc_zombie, which IIRC is not indicative of a bad access when zombies are enabled.

FIRMutableDictionary seem only happened with Zombie Objects. I closed Zombie Objects and
cannot reappearance.
What about [FIRASearchAdReporter scheduleSearchAdReport], I got 18 crashes in the last 7 days. Any suggestion? We will have a new release in a few days. I did update to the latest sdk and add UseCFPreferencesLibrary .

I'll try to fix FIRASearchAdReporter but the scheduled release won't be out until next month. Sorry for keeping you waiting.

Hello, I got a serious problem with the lastest sdk. [FIRAMeasurement monitor] crash 140 times in two days, most on iOS11.4.0, seems a deadlock with FIRAnalytics . Old crashes seems have been fixed in the lastest sdk.

the crash stack

device & system

other thread

Here the sdk version:

Using Firebase (5.3.0)
Using FirebaseAnalytics (5.0.1)
Using FirebaseCore (5.0.4)
Using FirebaseInstanceID (3.1.1)
Using FirebaseMessaging (3.0.2)
Using FirebasePerformance (2.0.1)
Using FirebaseSwizzlingUtilities (2.0.0)

Seems there have a singleton with FIRAMeasurement. When the signleton init, it calls [FIRAUserDefaults synchronize], and FIRAUserDefaults recall the singleton before the singleton finish.

@Lingyj : I have filed internal bug at b/110876085. The fix should be in the next release of Firebase Analytics. Thanks for reporting

The fix was shipped in Firebase 5.5.0 last week.