Fatal error. System.AccessViolationException

[paultobey]

xUnit 2.4.1

I'm getting intermittent crashes of a large, multiple test assembly, test set (1800+ tests, 4 test assemblies, 150 tests creating/using/dropping SQL Server databases):

dotnet test Core.sln --framework netcoreapp3.1 --no-build --no-restore --filter TestCategory!=Performance --verbosity normal >test2.out
The active test run was aborted. Reason: Test host process crashed : Fatal error. System.AccessViolationException: Attempted to read or write protected memory. This is often an indication that other memory is corrupt.
   at System.Diagnostics.StackTrace.GetStackFramesInternal(System.Diagnostics.StackFrameHelper, Int32, Boolean, System.Exception)
   at System.Diagnostics.StackFrameHelper.InitializeSourceInfo(Int32, Boolean, System.Exception)
   at System.Diagnostics.StackTrace.CaptureStackTrace(Int32, Boolean, System.Exception)
   at System.Diagnostics.StackTrace..ctor(System.Exception, Boolean)
   at System.Exception.get_StackTrace()
   at Xunit.Sdk.ExceptionUtility.ConvertExceptionToFailureInformation(System.Exception, Int32, System.Collections.Generic.List`1<System.String>, System.Collections.Generic.List`1<System.String>, System.Collections.Generic.List`1<System.String>, System.Collections.Generic.List`1<Int32>)
   at Xunit.Sdk.ExceptionUtility.ConvertExceptionToFailureInformation(System.Exception)
   at Xunit.Sdk.TestFailed..ctor(Xunit.Abstractions.ITest, System.Decimal, System.String, System.Exception)
   at Xunit.Sdk.TestRunner`1+<RunAsync>d__43[[System.__Canon, System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e]].MoveNext()
   at System.Runtime.CompilerServices.AsyncTaskMethodBuilder`1+AsyncStateMachineBox`1[[System.__Canon, System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e],[Xunit.Sdk.TestRunner`1+<RunAsync>d__43[[System.__Canon, System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e]], xunit.execution.dotnet, Version=2.4.1.0, Culture=neutral, PublicKeyToken=8d05b1bb7a6fdb6c]].ExecutionContextCallback(System.Object)
   at System.Threading.ExecutionContext.RunInternal(System.Threading.ExecutionContext, System.Threading.ContextCallback, System.Object)
   at System.Runtime.CompilerServices.AsyncTaskMethodBuilder`1+AsyncStateMachineBox`1[[System.__Canon, System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e],[Xunit.Sdk.TestRunner`1+<RunAsync>d__43[[System.__Canon, System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e]], xunit.execution.dotnet, Version=2.4.1.0, Culture=neutral, PublicKeyToken=8d05b1bb7a6fdb6c]].MoveNext(System.Threading.Thread)
   at System.Runtime.CompilerServices.AsyncTaskMethodBuilder`1+AsyncStateMachineBox`1[[System.__Canon, System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e],[Xunit.Sdk.TestRunner`1+<RunAsync>d__43[[System.__Canon, System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e]], xunit.execution.dotnet, Version=2.4.1.0, Culture=neutral, PublicKeyToken=8d05b1bb7a6fdb6c]].MoveNext()
   at System.Threading.Tasks.AwaitTaskContinuation.RunOrScheduleAction(System.Runtime.CompilerServices.IAsyncStateMachineBox, Boolean)
   at System.Threading.Tasks.Task.RunContinuations(System.Object)
   at System.Threading.Tasks.Task`1[[System.__Canon, System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e]].TrySetResult(System.__Canon)
   at System.Runtime.CompilerServices.AsyncTaskMethodBuilder`1[[System.__Canon, System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e]].SetResult(System.__Canon)
   at Xunit.Sdk.ExceptionAggregator+<RunAsync>d__10`1[[System.__Canon, System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e]].MoveNext()
   at System.Runtime.CompilerServices.AsyncTaskMethodBuilder`1+AsyncStateMachineBox`1[[System.__Canon, System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e],[Xunit.Sdk.ExceptionAggregator+<RunAsync>d__10`1[[System.__Canon, System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e]], xunit.core, Version=2.4.1.0, Culture=neutral, PublicKeyToken=8d05b1bb7a6fdb6c]].ExecutionContextCallback(System.Object)
   at System.Threading.ExecutionContext.RunInternal(System.Threading.ExecutionContext, System.Threading.ContextCallback, System.Object)
   at System.Runtime.CompilerServices.AsyncTaskMethodBuilder`1+AsyncStateMachineBox`1[[System.__Canon, System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e],[Xunit.Sdk.ExceptionAggregator+<RunAsync>d__10`1[[System.__Canon, System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e]], xunit.core, Version=2.4.1.0, Culture=neutral, PublicKeyToken=8d05b1bb7a6fdb6c]].MoveNext(System.Threading.Thread)
   at System.Runtime.CompilerServices.AsyncTaskMethodBuilder`1+AsyncStateMachineBox`1[[System.__Canon, System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e],[Xunit.Sdk.ExceptionAggregator+<RunAsync>d__10`1[[System.__Canon, System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e]], xunit.core, Version=2.4.1.0, Culture=neutral, PublicKeyToken=8d05b1bb7a6fdb6c]].MoveNext()
   at System.Threading.Tasks.AwaitTaskContinuation.RunOrScheduleAction(System.Runtime.CompilerServices.IAsyncStateMachineBox, Boolean)
   at System.Threading.Tasks.Task.RunContinuations(System.Object)
   at System.Threading.Tasks.Task`1[[System.__Canon, System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e]].TrySetResult(System.__Canon)
   at Xunit.Sdk.XunitTestRunner+<InvokeTestAsync>d__4.MoveNext()
   at System.Runtime.CompilerServices.AsyncTaskMethodBuilder`1+AsyncStateMachineBox`1[[System.__Canon, System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e],[Xunit.Sdk.XunitTestRunner+<InvokeTestAsync>d__4, xunit.execution.dotnet, Version=2.4.1.0, Culture=neutral, PublicKeyToken=8d05b1bb7a6fdb6c]].ExecutionContextCallback(System.Object)
   at System.Threading.ExecutionContext.RunInternal(System.Threading.ExecutionContext, System.Threading.ContextCallback, System.Object)
   at System.Runtime.CompilerServices.AsyncTaskMethodBuilder`1+AsyncStateMachineBox`1[[System.__Canon, System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e],[Xunit.Sdk.XunitTestRunner+<InvokeTestAsync>d__4, xunit.execution.dotnet, Version=2.4.1.0, Culture=neutral, PublicKeyToken=8d05b1bb7a6fdb6c]].MoveNext(System.Threading.Thread)
   at System.Runtime.CompilerServices.AsyncTaskMethodBuilder`1+AsyncStateMachineBox`1[[System.__Canon, System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e],[Xunit.Sdk.XunitTestRunner+<InvokeTestAsync>d__4, xunit.execution.dotnet, Version=2.4.1.0, Culture=neutral, PublicKeyToken=8d05b1bb7a6fdb6c]].MoveNext()
   at System.Threading.Tasks.AwaitTaskContinuation.RunOrScheduleAction(System.Runtime.CompilerServices.IAsyncStateMachineBox, Boolean)
   at System.Threading.Tasks.Task.RunContinuations(System.Object)
   at System.Threading.Tasks.Task`1[[System.Decimal, System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e]].TrySetResult(System.Decimal)
   at System.Runtime.CompilerServices.AsyncTaskMethodBuilder`1[[System.Decimal, System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e]].SetExistingTaskResult(System.Decimal)
   at System.Runtime.CompilerServices.AsyncTaskMethodBuilder`1[[System.Decimal, System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e]].SetResult(System.Decimal)
   at Xunit.Sdk.ExceptionAggregator+<RunAsync>d__10`1[[System.Decimal, System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e]].MoveNext()
   at System.Runtime.CompilerServices.AsyncTaskMethodBuilder`1+AsyncStateMachineBox`1[[System.Decimal, System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e],[Xunit.Sdk.ExceptionAggregator+<RunAsync>d__10`1[[System.Decimal, System.Private.CoreLib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e]], xunit.core, Version=2.4.1.0, Culture=neutral, PublicKeyToken=8d05b1bb7a6fdb6c]].ExecutionContextCallback(System.Object)
   at System.Threading.ExecutionContex
Test Run Aborted.

The point in the process at which the test crashes varies and there does not appear to be a correlation with any individual tests which are in process. Any command-line switches that would deliver better information? Any other suggestions? I'll try to set up memory dumps when it fails...

Thanks,
Paul T.

---

Update 1:

Here's a sample dump file when the error occurs:

dotnet.exe.34148.dmp.zip

[bradwilson]

This will require the full repro project to understand what's happening here. The stack trace indicates that we're reading the stack of an exception, that's accessing corrupted memory. It's not obvious why an exception object would be corrupted like this without knowing what the code under test is doing. In general, we don't do any unsafe code and/or unmanaged code via interop, so the actual bug is likely living elsewhere (like in the code under test, or in .NET itself).

Please open an issue with a repro project. Thanks!