Unable to reproduce crash from iOS App Review Team

Question

My latest mobile game update was promptly rejected by the iOS App Review Team for crashing after they pressed the "start" button to load the game scene from the main menu scene. Without providing a crash log, they told me to go reproduce the crash myself and then identify and fix the issue (lol yeah, sure thing buddy). I was unable to reproduce this issue so I spammed their inbox for three days and they finally provided me with a crash log. I'm unable to symbolicate the crash log in Xcode because I'm running MacOS on a virtual machine, which is unable to connect to a device (I refuse to buy a Mac just so I can publish free mobile games), so I've found myself at quite the dead end. I've attached the full crash log below. If anybody can help me understand what could be causing the crash, I'd greatly appreciate it. The crash is on Thread 0. I removed a lot of details from the log to fit it in the post so I can provide more information if needed.

Incident Identifier: E1CC2B12-75DA-4704-A9BA-9923B4EE44A3
CrashReporter Key:   d5a46eb6fe6765b9893f0126d9ae455c5b11cea1
Hardware Model:      xxx
Process:             AppName [4775]
Path:                /private/var/containers/Bundle/Application/8C49D650-D44B-40CA-9071-6EE143554D36/AppName.app/AppName
Identifier:          com.Company-Name.AppName
Version:             1 (1.0.8)
AppStoreTools:       12E262
Code Type:           ARM-64 (Native)
Role:                Foreground
Parent Process:      launchd [1]
Coalition:           com.Company-Name.AppName [1637]


Date/Time:           2021-05-06 15:53:25.8187 +0100
Launch Time:         2021-05-06 15:53:17.5422 +0100
OS Version:          iPhone OS 14.5.1 (18E212)
Release Type:        User
Baseband Version:    n/a
Report Version:      104

Exception Type:  EXC_BAD_ACCESS (SIGSEGV)
Exception Subtype: KERN_INVALID_ADDRESS at 0x0000000000000000
VM Region Info: 0 is not in any region.  Bytes before following region: 4376707072
      REGION TYPE                 START - END      [ VSIZE] PRT/MAX SHRMOD  REGION DETAIL
      UNUSED SPACE AT START
--->  
      __TEXT                   104df4000-104df8000 [   16K] r-x/r-x SM=COW  ...app/AppName

Triggered by Thread:  0

Thread 0 name:  Dispatch queue: com.apple.main-thread
Thread 0 Crashed:
0   libsystem_platform.dylib        0x00000001c993d128 0x1c9936000 + 28968
1   UnityFramework                  0x0000000105747228 0x105098000 + 7008808
2   UnityFramework                  0x00000001057530e8 0x105098000 + 7057640
3   UnityFramework                  0x000000010542fe74 0x105098000 + 3767924
4   UnityFramework                  0x0000000105710c10 0x105098000 + 6786064
5   UnityFramework                  0x000000010571226c 0x105098000 + 6791788
6   UnityFramework                  0x00000001057123b8 0x105098000 + 6792120
7   UnityFramework                  0x000000010557f470 0x105098000 + 5141616
8   UnityFramework                  0x000000010556f4b8 0x105098000 + 5076152
9   UnityFramework                  0x0000000105461350 0x105098000 + 3969872
10  UnityFramework                  0x00000001054621cc 0x105098000 + 3973580
11  UnityFramework                  0x0000000105463438 0x105098000 + 3978296
12  UnityFramework                  0x0000000105463ad8 0x105098000 + 3979992
13  UnityFramework                  0x00000001054562a4 0x105098000 + 3924644
14  UnityFramework                  0x00000001054562e4 0x105098000 + 3924708
15  UnityFramework                  0x00000001054565ac 0x105098000 + 3925420
16  UnityFramework                  0x000000010578cecc 0x105098000 + 7294668
17  UnityFramework                  0x00000001050b2290 0x105098000 + 107152
18  UnityFramework                  0x00000001050b21f8 0x105098000 + 107000
19  QuartzCore                      0x00000001851f98e4 0x1851e6000 + 80100
20  IOKit                           0x000000018c6ba0f8 0x18c6b3000 + 28920
21  CoreFoundation                  0x00000001820953dc 0x18201e000 + 488412
22  CoreFoundation                  0x00000001820b8fc0 0x18201e000 + 634816
23  CoreFoundation                  0x00000001820b83c4 0x18201e000 + 631748
24  CoreFoundation                  0x00000001820b2538 0x18201e000 + 607544
25  CoreFoundation                  0x00000001820b16a8 0x18201e000 + 603816
26  GraphicsServices                0x0000000198761570 0x19875e000 + 13680
27  UIKitCore                       0x00000001849cf370 0x183ea0000 + 11727728
28  UIKitCore                       0x00000001849d48ec 0x183ea0000 + 11749612
29  UnityFramework                  0x00000001050b1cc8 0x105098000 + 105672
30  AppName                         0x0000000104dfbe1c 0x104df4000 + 32284
31  libdyld.dylib                   0x0000000181d90140 0x181d8f000 + 4416    

Thread 0 crashed with ARM Thread State (64-bit):
    x0: 0x0000000000000000   x1: 0x00000002a0000060   x2: 0x0000000025bc53e0   x3: 0x0000000000000020
    x4: 0x0000000000000000   x5: 0x0000000000000020   x6: 0x0000000000000015   x7: 0x0000000000000000
    x8: 0xbf800000bde131b9   x9: 0x3f586c393f7178c0  x10: 0xb4000000b4000000  x11: 0xbe39a80dbcc13b57
   x12: 0xbe3db1abbca0ee69  x13: 0x3e8a242ebd91359d  x14: 0x3ea8e51ebf679701  x15: 0xbeaaa529bf6fb740
   x16: 0x00000001c993d0e0  x17: 0x0000000000000001  x18: 0x0000000000000000  x19: 0x0000000147b0e2e0
   x20: 0x00000002a0000020  x21: 0x0000000025bc5400  x22: 0x0000000000000000  x23: 0x000000014654f790
   x24: 0x0000000147b0e2e0  x25: 0x00000001456e4040  x26: 0x0000000000000000  x27: 0x000000014654f790
   x28: 0x0000000000000000   fp: 0x000000016b0090a0   lr: 0x0000000105747228
    sp: 0x000000016b009040   pc: 0x00000001c993d128 cpsr: 0x20000000
   esr: 0x56000080  Address size fault

Answer 1

You could try to use the atos command to symbolicate address. For example:

atos -arch arm64 -o UnityFramework.framework/UnityFramework -l 0x105098000 0x0000000105747228 0x00000001057530e8 0x000000010542fe74 ...and so on

-l option is followed by the base address of UnityFramework image, and next is stack addresses. Then you can see the symbols of functions call stack, find out where call the crash functions. These also apply to CoreFoundation, UIKitCore.

Answer 2

The error is pretty clear when reading through it. Firstly, the EXC_BAD_ACCESS (SIGSEGV) meaning it is accessing memory it should not be. Second, the KERN_INVALID_ADDRESS at 0x0000000000000000 is the address of NULL. In other words, you have a null reference exception that is being thrown when clicking start. As I can not see your code, I do not know the specifics. If you have any #if UNITY_IOS or #if UNITY_ANDROID conditions that section off code, it could be the iOS version is missing an assignment. If you want to learn more about understanding memory access crashes, read Apple's writeup.

I should add, this null reference exception might not be directly from your code. If you are using plugins or libraries in your project that runs differently on iOS, they might be the issue. As there is not a lot of information to go off from your question it is hard to say. Can you list any packages you could be using? Do you have an iPhone to test on personally? If not I would heavily consider at least finding someone with one to test your iOS game on instead of blindly publishing to a live environment.