Unity il2cpp项目Android端Firebase Crashlytics调用栈不准确问题

问题描述 #

• 在Unity IL2CPP项目中使用Firebase 10.7.0，Crashlytics可正常捕获崩溃与异常，但Android端调用栈存在异常：与Unity自带崩溃报告不符，所有线程均无libil2cpp.so或libunity.so条目。
• 主动触发崩溃验证时，Unity崩溃诊断中的调用栈显示正常（包含libunity.so、libil2cpp.so等关键库），但同一次崩溃的Firebase调用栈仅显示libc.so相关内容，完整栈追踪中也无上述Unity相关库，仅部分线程有libunitytuningfork.so引用，疑似来自其他进程。
• iOS端Crashlytics调用栈显示正常，仅Android端存在问题。我们希望继续使用Crashlytics，但Unity崩溃看板仅显示崩溃线程，对多线程问题排查帮助有限，寻求解决方法。

Unity崩溃诊断调用栈 #

Thread 0 (crashed)
0   libc.so                            0x00000000f3e64bac <symbols missing for uuid: 13bc715234d0861084dc092396cf9938> 
1   libunity.so                        0x00000000b43a54e1 Utils_CUSTOM_ForceCrash(DiagnosticsUtils_Bindings::ForcedCrashCategory) 
2   libil2cpp.so                       0x00000000045b71ec (unknown) (C:/workspace/workspace/p/Library/Bee/artifacts/Android/il2cppOutput/cpp\UnityEngine.CoreModule__3.cpp:0)
3   libil2cpp.so                       0x00000000b3a431f0 UnityEvent_Invoke_mFBF80D59B03C30C5FE6A06F897D954ACADE061D2 (C:/workspace/workspace/p/Library/Bee/artifacts/Android/il2cppOutput/cpp\UnityEngine.CoreModule__3.cpp:15108)
4   libil2cpp.so                       0x00000000045b71ec (unknown) (C:/workspace/workspace/p/Library/Bee/artifacts/Android/il2cppOutput/cpp\UnityEngine.CoreModule__3.cpp:0)
5   libil2cpp.so                       0x00000000b3a431f0 UnityEvent_Invoke_mFBF80D59B03C30C5FE6A06F897D954ACADE061D2 (C:/workspace/workspace/p/Library/Bee/artifacts/Android/il2cppOutput/cpp\UnityEngine.CoreModule__3.cpp:15108)
6   libil2cpp.so                       0x000000000198c63c EventFunction_1_Invoke_m98A8A653E7180305E41F7CFFDDD9D32C63B96FE7_gshared_inline (C:/workspace/workspace/p/Library/Bee/artifacts/Android/il2cppOutput/cpp\GenericMethods__34.cpp:44326)
7   libil2cpp.so                       0x000000000198c630 EventFunction_1_Invoke_m98A8A653E7180305E41F7CFFDDD9D32C63B96FE7_inline (C:/workspace/workspace/p/Library/Bee/artifacts/Android/il2cppOutput/cpp\GenericMethods__34.cpp:15124)
8   libil2cpp.so                       0x00000000b0e18644 ExecuteEvents_Execute_TisRuntimeObject_mDC4455B743BE4A6BA46DD741D0E0AB150FF1209A_gshared (C:/workspace/workspace/p/Library/Bee/artifacts/Android/il2cppOutput/cpp\GenericMethods__34.cpp:42151)
9   libil2cpp.so                       0x0000000004101004 ExecuteEvents_Execute_TisIPointerClickHandler_t77341AA19DE37C26F5F619DE8BD28B70D5A2B5D8_m024FB23AA1DBB1B7A5E1935FA35A1E4FF57AC5F6 (C:/workspace/workspace/p/Library/Bee/artifacts/Android/il2cppOutput/cpp\Unity.InputSystem__6.cpp:5169)
10  libil2cpp.so                       0x00000000b358d008 InputSystemUIInputModule_ProcessPointerButton_m68284C737796E80096AD8EAD1E0C687577131FE6 (C:/workspace/workspace/p/Library/Bee/artifacts/Android/il2cppOutput/cpp\Unity.InputSystem__6.cpp:8033)
11  libil2cpp.so                       0x00000000b358c590 InputSystemUIInputModule_ProcessPointer_mD889935190247CE78A8FE68ACA10CDD1C3B43E5D (C:/workspace/workspace/p/Library/Bee/artifacts/Android/il2cppOutput/cpp\Unity.InputSystem__6.cpp:6936)
12  libil2cpp.so                       0x00000000b3592c50 InputSystemUIInputModule_Process_mD46ECAA34DE552BF7178B12774FDF80ED24FB980 (C:/workspace/workspace/p/Library/Bee/artifacts/Android/il2cppOutput/cpp\Unity.InputSystem__6.cpp:13692)
13  libil2cpp.so                       0x00000000b076b344 il2cpp::vm::Runtime::InvokeWithThrow(MethodInfo const*, void*, void**) 
14  libil2cpp.so                       0x00000000b076b284 il2cpp::vm::Runtime::Invoke(MethodInfo const*, void*, void**, Il2CppException**) 
15  libunity.so                        0x00000000b4566e09 scripting_method_invoke(ScriptingMethodPtr, ScriptingObjectPtr, ScriptingArguments&, ScriptingExceptionPtr*, bool) 
16  libunity.so                        0x00000000b45725bd ScriptingInvocation::Invoke(ScriptingExceptionPtr*, bool) 
17  libunity.so                        0x00000000b457c455 MonoBehaviour::CallUpdateMethod(int) 
18  libunity.so                        0x00000000b4420a29 void BaseBehaviourManager::CommonUpdate<BehaviourManager>() 
19  libunity.so                        0x00000000b44b537f ExecutePlayerLoop(NativePlayerLoopSystem*) 
20  libunity.so                        0x00000000b44b53a1 ExecutePlayerLoop(NativePlayerLoopSystem*) 
21  libunity.so                        0x00000000b44b5583 PlayerLoop() 
22  libunity.so                        0x00000000b45cd87b UnityPlayerLoop() 
23  libunity.so                        0x00000000b45de387 nativeRender(_JNIEnv*, _jobject*) 
24  base.odex                          0x00000000c73869cb <symbols missing for uuid: 0000000000000000000000000000000000000000> 

Firebase调用栈 #

Crashed: Thread: SIGSEGV  0x0000000000001d86
#00 pc 0x9fbac libc.so (BuildId: 13bc715234d0861084dc092396cf9938)
#01 pc 0xbf7ffffe

解决方法 #

1. 上传正确的符号文件到Firebase #

• 构建Android包时，Unity会生成libil2cpp.so和libunity.so对应的符号文件，路径为Temp/gradleOut/build/intermediates/merged_native_libs/[buildType]/out/lib/[abi]/（比如arm64-v8a）。
• 确保这些符号文件被正确上传到Firebase：可以启用Unity Firebase插件的自动上传功能，或手动使用Firebase CLI的firebase crashlytics:symbols:upload命令上传。
• 若使用ProGuard混淆，需在规则中添加以下内容保护Unity相关库的符号：

  -keep class com.unity3d.player.** { *; }
  -keep class il2cpp.** { *; }
  -dontwarn com.unity3d.player.**
  -dontwarn il2cpp.**
  

2. 调整Firebase初始化时机 #

• 确保Firebase在Unity环境初始化完成后再启动，避免初始化顺序导致的捕获异常。可将Firebase初始化代码放在Start()方法中，或通过UnityPlayer相关回调确认环境就绪后执行初始化。

3. 排查崩溃捕获冲突 #

• 检查项目中是否同时启用了其他崩溃监控工具（如Unity Analytics崩溃功能），暂时禁用其他工具测试是否恢复正常。
• 确保Firebase Crashlytics是唯一的原生崩溃捕获工具，或调整捕获优先级。

4. 版本兼容性排查 #

• 尝试升级Firebase Unity SDK到最新稳定版，或降级到10.x系列内的其他兼容版本，排查是否为版本兼容性问题。
• 确认Unity版本与Firebase SDK版本兼容，参考官方兼容说明。

5. 手动捕获上报Unity异常 #

• 通过Unity的Application.logMessageReceivedThreaded事件手动捕获异常和崩溃信息，再调用Firebase接口上报，确保栈信息完整传递：

  void OnEnable()
  {
      Application.logMessageReceivedThreaded += HandleLog;
  }
  
  void OnDisable()
  {
      Application.logMessageReceivedThreaded -= HandleLog;
  }
  
  void HandleLog(string logString, string stackTrace, LogType type)
  {
      if (type == LogType.Exception || type == LogType.Error)
      {
          Firebase.Crashlytics.FirebaseCrashlytics.Instance.Log(logString);
          Firebase.Crashlytics.FirebaseCrashlytics.Instance.RecordException(new System.Exception(stackTrace));
      }
  }
  

内容的提问来源于stack exchange，提问作者Troy LFG