Test Crash: Microsoft.CodeAnalysis.VisualBasic.UnitTests.AsyncTests.Imported_AsyncWithEH

[333fred]

https://dev.azure.com/dnceng-public/public/_build/results?buildId=599758&view=ms.vss-test-web.build-test-results-tab&runId=14541768&resultId=188622&paneView=debug
https://github.com/dotnet/roslyn/pull/72499/checks?check_run_id=22567221018

The active test run was aborted. Reason: Test host process crashed : Unhandled exception. System.NullReferenceException: Object reference not set to an instance of an object.
   at System.Runtime.CompilerServices.AsyncVoidMethodBuilder.NotifySynchronizationContextOfCompletion()
--- End of stack trace from previous location ---
   at System.Threading.Tasks.Task.<>c.<ThrowAsync>b__128_1(Object state)
   at System.Threading.QueueUserWorkItemCallback.Execute()
   at System.Threading.ThreadPoolWorkQueue.Dispatch()
   at System.Threading.PortableThreadPool.WorkerThread.WorkerThreadStart()

Results File: C:\h\w\B1C0098E\w\AAFB0938\e\WorkItem_20_x64_test_results.xml

The active Test Run was aborted because the host process exited unexpectedly. Please inspect the call stack above, if available, to get more information about where the exception originated from.
The test running when the crash occurred: 
Microsoft.CodeAnalysis.VisualBasic.UnitTests.AsyncTests.Imported_AsyncWithEH

Dump (MSFT Internal only): https://microsoft-my.sharepoint.com/:u:/p/frsilb/ESIbrjR9gkpHp47XxFPO_7IBSBDDfNLSlDmLQ_YWX5Y1eg?e=hskNn4

[jaredpar]

Transfering to runtime as this appears to be a crash in AsyncVoidMethodBuilder using net8.0 runtime. The crash dump is throwing an NRE here:

        private void NotifySynchronizationContextOfCompletion()
        {
            Debug.Assert(_synchronizationContext != null, "Must only be used with a non-null context.");
            try
            {
                _synchronizationContext.OperationCompleted(); // NRE HERE
            }
            catch (Exception exc)

Locals aren't available (optimized code) but seems likely that _synchronizationContext is null here.

[reflectronic]

Is this the same as #99461?

[jaredpar]

It does indeed look like a dupe of that issue

[ericstj]

Resolving as I agree with @reflectronic and @jaredpar that this appears to be a dup of #99452 #93969 #40463, fixed in #99461 cc @stephentoub