CPPExceptionTerminate crash in iOS

Can someone help to figure out the root cause for this crash?

Please post a full crash report. For instructions on that, see Posting a Crash Report.

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Quinn “The Eskimo!” @ Developer Technical Support @ Apple
let myEmail = "eskimo" + "1" + "@" + "apple.com"

Please find the attached crash report

Thanks for the crash report.

Consider this:

Exception Type:  EXC_CRASH (SIGABRT)

It suggests that your app crash itself by calling abort. And the backtrace of the crashing thread confirms that:

Thread 0 name:
Thread 0 Crashed:
0   libsystem_kernel.dylib  … __pthread_kill + 8
1   libsystem_pthread.dylib … pthread_kill + 268 (pthread.c:1668)
2   libsystem_c.dylib       … __abort + 128 (abort.c:155)
3   libsystem_c.dylib       … abort + 180 (abort.c:126)
4   libc++abi.dylib         … abort_message + 132 (abort_message.cpp:78)
5   libc++abi.dylib         … demangling_terminate_handler() + 336 (cxa_default_handlers.cpp:71)
6   libobjc.A.dylib         … _objc_terminate() + 160 (objc-exception.mm:704)
7   UnityFramework          … CPPExceptionTerminate() + 496 (BSG_KSCrashSentry_CPPException.mm:192)
8   libc++abi.dylib         … std::__terminate(void (*)()) + 20 (cxa_handlers.cpp:59)
9   libc++abi.dylib         … std::terminate() + 64 (cxa_handlers.cpp:88)
10  libdispatch.dylib       … _dispatch_client_callout + 40 (object.m:563)

As you’ve noted already, frame 7 CPPExceptionTerminate is central to this. I’m not familiar with the third-party tool this comes from but, just based on that name and the source file, BSG_KSCrashSentry_CPPException.mm, it seems like that this is their custom crash reporter. My best guess here is that:

• In frame 10, Dispatch has called a block on the main queue.

• Something in that block has thrown an unhandled language exception.

• This has been caught by the third-party crash reporter.

What you’d like to know is the backtrace of the code that threw that exception. Normally that shows up in the Last Exception Backtrace section of the crash report, but that’s not present here. It’s likely that the third-party crash reporter is preventing that, either deliberately or accidentally [1].

My advice:

• If you can disable your third-party crash reporter, do so. I expect that’ll give you more actionable crash reports.

• If not, talk to your tool vendor to see if they have any advice on how to debug your issue.

Share and Enjoy
—
Quinn “The Eskimo!” @ Developer Technical Support @ Apple
let myEmail = "eskimo" + "1" + "@" + "apple.com"

[1] This is a common problem. See my Implementing Your Own Crash Reporter post for a lot more background on this issue.

Hi Eskimo,

Thanks for helping with this.

This crash randomly happens in my device, if I force close the app when game is on loading screen. As per my reproduction steps I can confirm this crash is not user facing. It is happening while app is terminating. Still we want to fix it, since we want to bring down our overall crash rates in App Store. Now, I disabled Bugsnag which is our third party crash reporter and reproduced the crash. Even in the latest crash report which does not have BSG_KSCrashSentry_CPPException.mm in it, I can't find Last Exception Backtrace. Can you please check the attached full crash report and let me know if we can find the root cause?

Thanks, Eshwar

Even in the latest crash report … I can't find Last Exception Backtrace.

Yeah, I think you’re hitting an annoying limitation of our crash reporting system. Based on the other backtraces in your crash report, it’s likely that crash is being caused by a C++ language exception and those don’t record the backtrace. See this thread for the full backstory.

On the plus side, you can reproduce this reasonably easily, which gives you more options than other folks. Are you able to reproduce it with the Xcode debugger attached?

Share and Enjoy
—
Quinn “The Eskimo!” @ Developer Technical Support @ Apple
let myEmail = "eskimo" + "1" + "@" + "apple.com"

Hi Eskimo,

I was able to debug the issue by attaching Xcode debugger which helped me to locate the unhandled exception that was happening in app backgrounding flow. Fixing that exception helped to fix the crash as well. Thanks for your help.

Thanks, Eshwar