Test failure: Assertion failed. state is RuntimeAsyncTask<T>

[jkotas]

  Starting:    System.Threading.Channels.Tests (parallel test collections = on [2 threads], stop on fail = off)
Process terminated.
Assertion failed.
state is RuntimeAsyncTask<T>
   at System.Runtime.CompilerServices.AsyncHelpers.RuntimeAsyncTask`1.<>c.<.cctor>b__16_1(Object state) in /_/src/coreclr/System.Private.CoreLib/src/System/Runtime/CompilerServices/AsyncHelpers.CoreCLR.cs:line 711
   at System.Threading.Channels.ChannelUtilities.DangerousSetOperations[TAsyncOp,TResult](TAsyncOp head, TResult result) in /_/src/libraries/System.Threading.Channels/src/System/Threading/Channels/ChannelUtilities.cs:line 245
   at System.Threading.Channels.UnboundedChannel`1.UnboundedChannelWriter.TryWrite(T item) in /_/src/libraries/System.Threading.Channels/src/System/Threading/Channels/UnboundedChannel.cs:line 281
   at System.Threading.Channels.UnboundedChannel`1.UnboundedChannelWriter.WriteAsync(T item, CancellationToken cancellationToken) in /_/src/libraries/System.Threading.Channels/src/System/Threading/Channels/UnboundedChannel.cs:line 298
   at System.Threading.Channels.Tests.ChannelTestBase.<>c__DisplayClass26_0.<ManyProducerConsumer_ConcurrentReadWrite_Success>b__1() in /_/src/libraries/System.Threading.Channels/tests/ChannelTestBase.cs:line 248
   at System.Threading.Tasks.Task`1.InnerInvoke() in /_/src/libraries/System.Private.CoreLib/src/System/Threading/Tasks/Task_T.cs:line 486
   at System.Threading.ExecutionContext.RunFromThreadPoolDispatchLoop(Thread threadPoolThread, ExecutionContext executionContext, ContextCallback callback, Object state) in /_/src/libraries/System.Private.CoreLib/src/System/Threading/ExecutionContext.cs:line 279
   at System.Threading.Tasks.Task.ExecuteWithThreadLocal(Task& currentTaskSlot, Thread threadPoolThread) in /_/src/libraries/System.Private.CoreLib/src/System/Threading/Tasks/Task.cs:line 2424
   at System.Threading.ThreadPoolWorkQueue.Dispatch() in /_/src/libraries/System.Private.CoreLib/src/System/Threading/ThreadPoolWorkQueue.cs:line 950
   at System.Threading.PortableThreadPool.WorkerThread.WorkerDoWork(PortableThreadPool threadPoolInstance) in /_/src/libraries/System.Private.CoreLib/src/System/Threading/PortableThreadPool.WorkerThread.cs:line 134
   at System.Threading.PortableThreadPool.WorkerThread.WorkerThreadStart() in /_/src/libraries/System.Private.CoreLib/src/System/Threading/PortableThreadPool.WorkerThread.cs:line 110
   at System.Threading.Thread.StartCallback() in /_/src/coreclr/System.Private.CoreLib/src/System/Threading/Thread.CoreCLR.cs:line 116
[createdump] Gathering state for process 34 dotnet

Build Information

Build: https://dev.azure.com/dnceng-public/cbb18261-c48f-4abb-8651-8cdcb5474649/_build/results?buildId=1314345
Build error leg or test failing: System.Threading.Channels.Tests.WorkItemExecution
Pull request: #124725

Error Message

Fill the error message using step by step known issues guidance.

{
  "ErrorMessage": "state is RuntimeAsyncTask<T>",
  "ErrorPattern": "",
  "BuildRetry": false,
  "ExcludeConsoleLog": false
}

Known issue validation

Build: 🔎 https://dev.azure.com/dnceng-public/public/_build/results?buildId=1314345
Error message validated: [state is RuntimeAsyncTask<T>]
Result validation: ✅ Known issue matched with the provided build.
Validation performed at: 2/28/2026 8:10:46 PM UTC

Report

Build	Definition	Test	Pull Request
1356861	dotnet/runtime	System.Threading.Channels.Tests.WorkItemExecution
1356722	dotnet/runtime	System.Threading.Channels.Tests.WorkItemExecution	#125900
1356463	dotnet/runtime	System.Threading.Channels.Tests.WorkItemExecution	#126231
1352252	dotnet/runtime	System.Threading.Channels.Tests.WorkItemExecution	#126091
1343605	dotnet/runtime	System.Threading.Channels.Tests.WorkItemExecution	#125759
1340863	dotnet/runtime	System.Threading.Channels.Tests.WorkItemExecution	#125436
1335001	dotnet/runtime	System.Threading.Channels.Tests.WorkItemExecution	#124920
1328950	dotnet/runtime	System.Threading.Channels.Tests.WorkItemExecution	#125211
1324436	dotnet/runtime	System.Threading.Channels.Tests.WorkItemExecution	#125282
1318669	dotnet/runtime	System.Threading.Channels.Tests.WorkItemExecution	#123819

Summary

24-Hour Hit Count	7-Day Hit Count	1-Month Count
0	4	10

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