Debugging Crashlog - Crashes in Testflight but not in simulator

I am creating a build using the command 'eas build -p ios' and when launching on testflight it crashes immediately. This is the crashlog testflight gives me. I have added a portion of it below. If more of it is needed let me know.

I have also tried using hermes as my js engine. How can I debug this?

Incident Identifier: D852C7FE-DF24-4B5C-9D9C-E3CCD8E00734
Hardware Model:      iPhone12,1
Process:             AppName [9237]
Path:                /private/var/containers/Bundle/Application/C015CF31-46C4-4B23-BE7F-7B91E29F1DC7/AppName.app/AppName
Identifier:          io.AppNameapp
Version:             1.0.0 (1)
AppStoreTools:       14C17
AppVariant:          1:iPhone12,1:16
Beta:                YES
Code Type:           ARM-64 (Native)
Role:                Foreground
Parent Process:      launchd [1]
Coalition:           io.AppNameapp [1630]

Date/Time:           2023-01-21 14:33:46.3007 -0500
Launch Time:         2023-01-21 14:33:44.9342 -0500
OS Version:          iPhone OS 16.2 (20C65)
Release Type:        User
Baseband Version:    4.00.00
Report Version:      104

Exception Type:  EXC_CRASH (SIGABRT)
Exception Codes: 0x0000000000000000, 0x0000000000000000
Triggered by Thread:  2

Last Exception Backtrace:
0   CoreFoundation                  0x1b042de48 __exceptionPreprocess + 164 (NSException.m:202)
1   libobjc.A.dylib                 0x1a97038d8 objc_exception_throw + 60 (objc-exception.mm:356)
2   AppName                             0x104ad7040 RCTFatal + 668 (RCTAssert.m:147)
3   AppName                             0x104b57398 -[RCTExceptionsManager reportFatal:stack:exceptionId:extraDataAsJSON:] + 532 (RCTExceptionsManager.mm:77)
4   AppName                             0x104b57cd8 -[RCTExceptionsManager reportException:] + 1476 (RCTExceptionsManager.mm:147)
5   CoreFoundation                  0x1b04986c4 __invoking___ + 148 (:-1)
6   CoreFoundation                  0x1b0444b2c -[NSInvocation invoke] + 428 (NSForwarding.m:3377)
7   CoreFoundation                  0x1b0444544 -[NSInvocation invokeWithTarget:] + 64 (NSForwarding.m:3474)
8   AppName                             0x104b097e4 -[RCTModuleMethod invokeWithBridge:module:arguments:] + 460 (RCTModuleMethod.mm:584)
9   AppName                             0x104b0bdd0 facebook::react::invokeInner(RCTBridge*, RCTModuleData*, unsigned int, folly::dynamic const&, int, (anonymous namespace)::SchedulingContext) + 536 (RCTNativeModule.mm:183)
10  AppName                             0x104b0ba04 operator() + 68 (RCTNativeModule.mm:104)
11  AppName                             0x104b0ba04 invocation function for block in facebook::react::RCTNativeModule::invoke(unsigned int, folly::dynamic&&, int) + 112 (RCTNativeModule.mm:95)
12  libdispatch.dylib               0x1b7a3f4b4 _dispatch_call_block_and_release + 32 (init.c:1518)
13  libdispatch.dylib               0x1b7a40fdc _dispatch_client_callout + 20 (object.m:560)
14  libdispatch.dylib               0x1b7a48694 _dispatch_lane_serial_drain + 672 (inline_internal.h:2632)
15  libdispatch.dylib               0x1b7a491e0 _dispatch_lane_invoke + 384 (queue.c:3940)
16  libdispatch.dylib               0x1b7a53e10 _dispatch_workloop_worker_thread + 652 (queue.c:6846)
17  libsystem_pthread.dylib         0x1fe4b5df8 _pthread_wqthread + 288 (pthread.c:2618)
18  libsystem_pthread.dylib         0x1fe4b5b98 start_wqthread + 8 (:-1)

...

Thread 2 name:
Thread 2 Crashed:
0   libsystem_kernel.dylib          0x00000001edd9f160 __pthread_kill + 8 (:-1)
1   libsystem_pthread.dylib         0x00000001fe4bc1ac pthread_kill + 268 (pthread.c:1670)
2   libsystem_c.dylib               0x00000001b7aa4c8c abort + 180 (abort.c:118)
3   libc++abi.dylib                 0x00000001fe3fbb8c abort_message + 132 (abort_message.cpp:78)
4   libc++abi.dylib                 0x00000001fe3eba80 demangling_terminate_handler() + 336 (cxa_default_handlers.cpp:71)
5   libobjc.A.dylib                 0x00000001a9709d3c _objc_terminate() + 144 (objc-exception.mm:498)
6   libc++abi.dylib                 0x00000001fe3faf28 std::__terminate(void (*)()) + 20 (cxa_handlers.cpp:59)
7   libc++abi.dylib                 0x00000001fe3faec4 std::terminate() + 56 (cxa_handlers.cpp:88)
8   libdispatch.dylib               0x00000001b7a40ff0 _dispatch_client_callout + 40 (object.m:563)
9   libdispatch.dylib               0x00000001b7a48694 _dispatch_lane_serial_drain + 672 (inline_internal.h:2632)
10  libdispatch.dylib               0x00000001b7a491e0 _dispatch_lane_invoke + 384 (queue.c:3940)
11  libdispatch.dylib               0x00000001b7a53e10 _dispatch_workloop_worker_thread + 652 (queue.c:6846)
12  libsystem_pthread.dylib         0x00000001fe4b5df8 _pthread_wqthread + 288 (pthread.c:2618)
13  libsystem_pthread.dylib         0x00000001fe4b5b98 start_wqthread + 8 (:-1)


How can I debug this?

The presence of the Last Exception Backtrace section indicates that your app is crashing due to an unhandled language exception. Look at its backtrace:

Last Exception Backtrace:
0   CoreFoundation          … __exceptionPreprocess + 164 (NSException.m:202)
1   libobjc.A.dylib         … objc_exception_throw + 60 (objc-exception.mm:356)
2   AppName                 … RCTFatal + 668 (RCTAssert.m:147)
3   AppName                 … -[RCTExceptionsManager reportFatal:stack:exceptionId:extraDataAsJSON:] + 532 (RCTExceptionsManager.mm:77)
4   AppName                 … -[RCTExceptionsManager reportException:] + 1476 (RCTExceptionsManager.mm:147)
5   CoreFoundation          … __invoking___ + 148 (:-1)
6   CoreFoundation          … -[NSInvocation invoke] + 428 (NSForwarding.m:3377)
7   CoreFoundation          … -[NSInvocation invokeWithTarget:] + 64 (NSForwarding.m:3474)
8   AppName                 … -[RCTModuleMethod invokeWithBridge:module:arguments:] + 460 (RCTModuleMethod.mm:584)
9   AppName                 … facebook::react::invokeInner(RCTBridge*, RCTModuleData*, unsigned int, folly::dynamic const&, int, (anonymous namespace)::SchedulingContext) + 536 (RCTNativeModule.mm:183)
10  AppName                 … operator() + 68 (RCTNativeModule.mm:104)
11  AppName                 … invocation function for block in facebook::react::RCTNativeModule::invoke(unsigned int, folly::dynamic&&, int) + 112 (RCTNativeModule.mm:95)
12  libdispatch.dylib       … _dispatch_call_block_and_release + 32 (init.c:1518)

Frames 4 through 2 suggest that this problem is causing by an error coming out of your third-party runtime. You’ll have to consult the support resources for that runtime to work out what’s gone wrong.

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

Thank you for the insight! Is there a way I can determine which third party library its coming from or will I have to go through the process of guessing and checking?

The cause of my crash was from the library react-native-snap-carousel. After upgrading from 3.9.1 to 4.0.0-beta.6, the crashing stopped.

Before

"react-native-snap-carousel": "3.9.1",

After

"react-native-snap-carousel": "4.0.0-beta.6",

@priedejm how did you go about debugging this? Did you go 1-by-1 removing libraries and dependencies until you got testflight to not crash?

Hello @priedejm, I'm having the exact same problem but i dont use snap-carousel, how did you find out which third party module was causing this crash ?

Thanks in advance !

Debugging Crashlog - Crashes in Testflight but not in simulator
 
 
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