RISCV64 stacktrace test fails with NativeAOT due to missing context

[am11]

After running all libraries and runtime tests in AOT mode on linux-riscv64 machine, I have found one issue:

This assertion fails:

runtime/src/libraries/System.Net.Http/tests/FunctionalTests/HttpClientTest.cs

Line 1634 in 46b72c7

Assert.Contains(nameof(InterestingMethodInTheStackTrace), exceptionText);

I added a debug (Console.Write) line and found this:

am11@k1:~/naottstlibs/http$ lldb -- ./System.Net.Http.Functional.Tests -method System.Net.Http.Functional.Tests.HttpClientSendTest_Async.Send_InnerHandlerThrows_OriginalExceptionInformationIsCaptured
SOS_HOSTING: Failed to find runtime directory
Unrecognized command 'setsymbolserver' because managed hosting failed or was disabled. See sethostruntime command for details.
(lldb) target create "./System.Net.Http.Functional.Tests"
Current executable set to '/home/am11/naottstlibs/http/System.Net.Http.Functional.Tests' (riscv64).
(lldb) settings set -- target.run-args "-method" "System.Net.Http.Functional.Tests.HttpClientSendTest_Async.Send_InnerHandlerThrows_OriginalExceptionInformationIsCaptured"
(lldb) r
Process 3844930 launched: '/home/am11/naottstlibs/http/System.Net.Http.Functional.Tests' (riscv64)
Running assembly:System.Net.Http.Functional.Tests, Version=11.0.0.0, Culture=neutral, PublicKeyToken=cc7b13ffcd2ddd51
===== OperationCanceledException_WithOriginalCancellationToken BEGIN exceptionText =====
System.Threading.Tasks.TaskCanceledException: Useful information
 ---> System.OperationCanceledException: Useful information
 ---> System.Exception: Useful inner exception information
 --- End of inner exception stack trace ---
 at System.Net.Http.HttpClient.<SendAsync>g__Core|83_0(HttpRequestMessage, HttpCompletionOption, CancellationTokenSource, Boolean, CancellationTokenSource, CancellationToken) in /runtime/src/libraries/System.Net.Http/src/System/Net/Http/HttpClient.cs:line 544
 --- End of inner exception stack trace ---
 at System.Net.Http.HttpClient.HandleFailure(Exception, Boolean, HttpResponseMessage, CancellationTokenSource, CancellationToken, CancellationTokenSource) in /runtime/src/libraries/System.Net.Http/src/System/Net/Http/HttpClient.cs:line 644
 at System.Net.Http.HttpClient.<SendAsync>g__Core|83_0(HttpRequestMessage, HttpCompletionOption, CancellationTokenSource, Boolean, CancellationTokenSource, CancellationToken) in /runtime/src/libraries/System.Net.Http/src/System/Net/Http/HttpClient.cs:line 564
--- End of stack trace from previous location ---
 at Xunit.Assert.<RecordExceptionAsync>d__215.MoveNext() in /_/src/arcade/src/Microsoft.DotNet.XUnitAssert/src/Record.cs:line 139
===== OperationCanceledException_WithOriginalCancellationToken END exceptionText =====
[FAIL] System.Net.Http.Functional.Tests.HttpClientSendTest_Async.Send_InnerHandlerThrows_OriginalExceptionInformationIsCaptured(scenario: OperationCanceledException_WithOriginalCancellationToken)
Assert.Contains() Failure: Sub-string not found
String: "System.Threading.Tasks.TaskCanceledException: Usef"···
Not found: "InterestingMethodInTheStackTrace"
 at System.Net.Http.Functional.Tests.HttpClientTest.HttpClientSendTest.Send_InnerHandlerThrows_OriginalExceptionInformationIsCaptured(HttpClientTest.HttpClientSendTest.ExceptionScenario) in /runtime/src/libraries/System.Net.Http/tests/FunctionalTests/HttpClientTest.cs:line 1636
--- End of stack trace from previous location ---
--- End of stack trace from previous location ---
--- End of stack trace from previous location ---
===== OperationCanceledException_UnknownCancellationToken BEGIN exceptionText =====
System.Threading.Tasks.TaskCanceledException: Useful information
 ---> System.OperationCanceledException: Useful information
 ---> System.Exception: Useful inner exception information
 --- End of inner exception stack trace ---
 at System.Net.Http.HttpClient.<SendAsync>g__Core|83_0(HttpRequestMessage, HttpCompletionOption, CancellationTokenSource, Boolean, CancellationTokenSource, CancellationToken) in /runtime/src/libraries/System.Net.Http/src/System/Net/Http/HttpClient.cs:line 544
 --- End of inner exception stack trace ---
 at System.Net.Http.HttpClient.HandleFailure(Exception, Boolean, HttpResponseMessage, CancellationTokenSource, CancellationToken, CancellationTokenSource) in /runtime/src/libraries/System.Net.Http/src/System/Net/Http/HttpClient.cs:line 644
 at System.Net.Http.HttpClient.<SendAsync>g__Core|83_0(HttpRequestMessage, HttpCompletionOption, CancellationTokenSource, Boolean, CancellationTokenSource, CancellationToken) in /runtime/src/libraries/System.Net.Http/src/System/Net/Http/HttpClient.cs:line 564
--- End of stack trace from previous location ---
 at Xunit.Assert.<RecordExceptionAsync>d__215.MoveNext() in /_/src/arcade/src/Microsoft.DotNet.XUnitAssert/src/Record.cs:line 139
===== OperationCanceledException_UnknownCancellationToken END exceptionText =====
[FAIL] System.Net.Http.Functional.Tests.HttpClientSendTest_Async.Send_InnerHandlerThrows_OriginalExceptionInformationIsCaptured(scenario: OperationCanceledException_UnknownCancellationToken)
Assert.Contains() Failure: Sub-string not found
String: "System.Threading.Tasks.TaskCanceledException: Usef"···
Not found: "InterestingMethodInTheStackTrace"
 at System.Net.Http.Functional.Tests.HttpClientTest.HttpClientSendTest.Send_InnerHandlerThrows_OriginalExceptionInformationIsCaptured(HttpClientTest.HttpClientSendTest.ExceptionScenario) in /runtime/src/libraries/System.Net.Http/tests/FunctionalTests/HttpClientTest.cs:line 1636
--- End of stack trace from previous location ---
--- End of stack trace from previous location ---
--- End of stack trace from previous location ---
===== HttpRequestException BEGIN exceptionText =====
System.Net.Http.HttpRequestException: Useful information
 ---> System.Exception: Useful inner exception information
 --- End of inner exception stack trace ---
 at System.Net.Http.Functional.Tests.HttpClientTest.HttpClientSendTest.<Send_InnerHandlerThrows_OriginalExceptionInformationIsCaptured>g__InterestingMethodInTheStackTrace|6_1(Func`1 exceptionFactory) in /runtime/src/libraries/System.Net.Http/tests/FunctionalTests/HttpClientTest.cs:line 1639
 at System.Net.Http.Functional.Tests.HttpClientTest.HttpClientSendTest.<>c__DisplayClass6_0.<Send_InnerHandlerThrows_OriginalExceptionInformationIsCaptured>b__0(HttpRequestMessage, CancellationToken) in /runtime/src/libraries/System.Net.Http/tests/FunctionalTests/HttpClientTest.cs:line 1607
 at System.Net.Http.Functional.Tests.HttpClientTest.HttpClientSendTest.<>c__DisplayClass6_0.<Send_InnerHandlerThrows_OriginalExceptionInformationIsCaptured>b__0(HttpRequestMessage _, CancellationToken cancellationToken)
--- End of stack trace from previous location ---
 at System.Net.Http.HttpClient.<SendAsync>g__Core|83_0(HttpRequestMessage, HttpCompletionOption, CancellationTokenSource, Boolean, CancellationTokenSource, CancellationToken) in /runtime/src/libraries/System.Net.Http/src/System/Net/Http/HttpClient.cs:line 544
--- End of stack trace from previous location ---
 at Xunit.Assert.<RecordExceptionAsync>d__215.MoveNext() in /_/src/arcade/src/Microsoft.DotNet.XUnitAssert/src/Record.cs:line 139
===== HttpRequestException END exceptionText =====
===== HttpRequestException_DuringCancellation BEGIN exceptionText =====
System.Threading.Tasks.TaskCanceledException: The operation was canceled.
 ---> System.Net.Http.HttpRequestException: Useful information
 ---> System.Exception: Useful inner exception information
 --- End of inner exception stack trace ---
 at System.Net.Http.HttpClient.<SendAsync>g__Core|83_0(HttpRequestMessage, HttpCompletionOption, CancellationTokenSource, Boolean, CancellationTokenSource, CancellationToken) in /runtime/src/libraries/System.Net.Http/src/System/Net/Http/HttpClient.cs:line 544
 --- End of inner exception stack trace ---
 at System.Net.Http.HttpClient.HandleFailure(Exception, Boolean, HttpResponseMessage, CancellationTokenSource, CancellationToken, CancellationTokenSource) in /runtime/src/libraries/System.Net.Http/src/System/Net/Http/HttpClient.cs:line 644
 at System.Net.Http.HttpClient.<SendAsync>g__Core|83_0(HttpRequestMessage, HttpCompletionOption, CancellationTokenSource, Boolean, CancellationTokenSource, CancellationToken) in /runtime/src/libraries/System.Net.Http/src/System/Net/Http/HttpClient.cs:line 564
--- End of stack trace from previous location ---
 at Xunit.Assert.<RecordExceptionAsync>d__215.MoveNext() in /_/src/arcade/src/Microsoft.DotNet.XUnitAssert/src/Record.cs:line 139
===== HttpRequestException_DuringCancellation END exceptionText =====
[FAIL] System.Net.Http.Functional.Tests.HttpClientSendTest_Async.Send_InnerHandlerThrows_OriginalExceptionInformationIsCaptured(scenario: HttpRequestException_DuringCancellation)
Assert.Contains() Failure: Sub-string not found
String: "System.Threading.Tasks.TaskCanceledException: The "···
Not found: "InterestingMethodInTheStackTrace"
 at System.Net.Http.Functional.Tests.HttpClientTest.HttpClientSendTest.Send_InnerHandlerThrows_OriginalExceptionInformationIsCaptured(HttpClientTest.HttpClientSendTest.ExceptionScenario) in /runtime/src/libraries/System.Net.Http/tests/FunctionalTests/HttpClientTest.cs:line 1636
--- End of stack trace from previous location ---
--- End of stack trace from previous location ---
--- End of stack trace from previous location ---
===== UnknownException BEGIN exceptionText =====
System.Exception: Useful information
 ---> System.Exception: Useful inner exception information
 --- End of inner exception stack trace ---
 at System.Net.Http.Functional.Tests.HttpClientTest.HttpClientSendTest.<Send_InnerHandlerThrows_OriginalExceptionInformationIsCaptured>g__InterestingMethodInTheStackTrace|6_1(Func`1 exceptionFactory) in /runtime/src/libraries/System.Net.Http/tests/FunctionalTests/HttpClientTest.cs:line 1639
 at System.Net.Http.Functional.Tests.HttpClientTest.HttpClientSendTest.<>c__DisplayClass6_0.<Send_InnerHandlerThrows_OriginalExceptionInformationIsCaptured>b__0(HttpRequestMessage, CancellationToken) in /runtime/src/libraries/System.Net.Http/tests/FunctionalTests/HttpClientTest.cs:line 1613
 at System.Net.Http.Functional.Tests.HttpClientTest.HttpClientSendTest.<>c__DisplayClass6_0.<Send_InnerHandlerThrows_OriginalExceptionInformationIsCaptured>b__0(HttpRequestMessage _, CancellationToken cancellationToken)
--- End of stack trace from previous location ---
 at System.Net.Http.HttpClient.<SendAsync>g__Core|83_0(HttpRequestMessage, HttpCompletionOption, CancellationTokenSource, Boolean, CancellationTokenSource, CancellationToken) in /runtime/src/libraries/System.Net.Http/src/System/Net/Http/HttpClient.cs:line 544
--- End of stack trace from previous location ---
 at Xunit.Assert.<RecordExceptionAsync>d__215.MoveNext() in /_/src/arcade/src/Microsoft.DotNet.XUnitAssert/src/Record.cs:line 139
===== UnknownException END exceptionText =====
===== UnknownException_DuringCancellation BEGIN exceptionText =====
System.Exception: Useful information
 ---> System.Exception: Useful inner exception information
 --- End of inner exception stack trace ---
 at System.Net.Http.HttpClient.<SendAsync>g__Core|83_0(HttpRequestMessage, HttpCompletionOption, CancellationTokenSource, Boolean, CancellationTokenSource, CancellationToken) in /runtime/src/libraries/System.Net.Http/src/System/Net/Http/HttpClient.cs:line 544
--- End of stack trace from previous location ---
 at Xunit.Assert.<RecordExceptionAsync>d__215.MoveNext() in /_/src/arcade/src/Microsoft.DotNet.XUnitAssert/src/Record.cs:line 139
===== UnknownException_DuringCancellation END exceptionText =====
[FAIL] System.Net.Http.Functional.Tests.HttpClientSendTest_Async.Send_InnerHandlerThrows_OriginalExceptionInformationIsCaptured(scenario: UnknownException_DuringCancellation)
Assert.Contains() Failure: Sub-string not found
String: "System.Exception: Useful information\n ---> System."···
Not found: "InterestingMethodInTheStackTrace"
 at System.Net.Http.Functional.Tests.HttpClientTest.HttpClientSendTest.Send_InnerHandlerThrows_OriginalExceptionInformationIsCaptured(HttpClientTest.HttpClientSendTest.ExceptionScenario) in /runtime/src/libraries/System.Net.Http/tests/FunctionalTests/HttpClientTest.cs:line 1636
--- End of stack trace from previous location ---
--- End of stack trace from previous location ---
--- End of stack trace from previous location ---
Finished System.Net.Http.Functional.Tests, Version=11.0.0.0, Culture=neutral, PublicKeyToken=cc7b13ffcd2ddd51

Tests run: 6, Errors: 0, Failures: 4, Skipped: 0. Time: 0.1947178s
Process 3844930 exited with status = 1 (0x00000001) 
(lldb) q

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[am11]

cc @dotnet/samsung, @filipnavara,

Build steps:

# on osx-arm64
$ cd runtime
$ docker run --rm -v$(pwd):/runtime -w /runtime -e ROOTFS_DIR=/crossrootfs/riscv64 -it ubuntu
$ eng/common/native/install-dependencies.sh
$ apt install -y python3-venv
$ rootfsEnv="/usr/local/share/rootfs" && python3 -m venv "$rootfsEnv" && "$rootfsEnv/bin/python" -m pip install aiohttp zstandard && PYTHON_EXECUTABLE="$rootfsEnv/bin/python" ./eng/common/cross/build-rootfs.sh riscv64 noble --skipunmount --skipemulation
$ os=linux; arch=riscv64

$ ./build.sh clr+libs --cross --arch $arch --os $os -c Release --bootstrap
$ ./build.sh libs.tests --cross --arch $arch --os $os --use-bootstrap -c Release -p:TestNativeAot=true -p:ArchiveTests=true

Then scp test archive to riscv64 computer (k1) and run tests:

# from os-x64
$ scp artifacts/helix/tests/linux.AnyCPU.Release/System.Net.Http.Functional.Tests.zip k1:/tmp
$ ssh k1
$ mkdir -p ~/naottstlibs/http && cd $_
$ unzip /tmp/System.Net.Http.Functional.Tests.zip &>/dev/null

# run full HTTP test suite
$ ./RunTests.sh --runtime-path foo # foo is needed just to satisfy this script; it doesn't use corerun in AOT mode...

# run this specific test
$ ./System.Net.Http.Functional.Tests -method System.Net.Http.Functional.Tests.HttpClientSendTest_Async.Send_InnerHandlerThrows_OriginalExceptionInformationIsCaptured

[am11]

It probably doesn't capture context around async resumption (runtime async?); the sync variant of this test passes.

[am11]

On linux-arm64, it passes:

$ root@426b2454e6c3:/httptst# ./System.Net.Http.Functional.Tests -method System.Net.Http.Functional.Tests.HttpClientSendTest_Async.Send_InnerHandlerThrows_OriginalExceptionInformationIsCaptured
Running assembly:System.Net.Http.Functional.Tests, Version=11.0.0.0, Culture=neutral, PublicKeyToken=cc7b13ffcd2ddd51
===== OperationCanceledException_WithOriginalCancellationToken BEGIN exceptionText =====
System.Threading.Tasks.TaskCanceledException: Useful information
 ---> System.OperationCanceledException: Useful information
 ---> System.Exception: Useful inner exception information
 --- End of inner exception stack trace ---
 at System.Net.Http.Functional.Tests.HttpClientTest.HttpClientSendTest.<Send_InnerHandlerThrows_OriginalExceptionInformationIsCaptured>g__InterestingMethodInTheStackTrace|6_1(Func`1 exceptionFactory) in /runtime/src/libraries/System.Net.Http/tests/FunctionalTests/HttpClientTest.cs:line 1639
 at System.Net.Http.Functional.Tests.HttpClientTest.HttpClientSendTest.<>c__DisplayClass6_0.<Send_InnerHandlerThrows_OriginalExceptionInformationIsCaptured>b__0(HttpRequestMessage, CancellationToken) in /runtime/src/libraries/System.Net.Http/tests/FunctionalTests/HttpClientTest.cs:line 1596
--- End of stack trace from previous location ---
 at System.Runtime.CompilerServices.RuntimeAsyncTaskContinuation.GetResult[T](Task, Byte&) in /runtime/src/coreclr/System.Private.CoreLib/src/System/Runtime/CompilerServices/RuntimeAsyncTaskContinuation.cs:line 140
 at System.Runtime.CompilerServices.RuntimeAsyncTaskContinuation.TaskContinuationResume.ResumeTaskContinuation(Continuation, Byte&) in /runtime/src/coreclr/System.Private.CoreLib/src/System/Runtime/CompilerServices/RuntimeAsyncTaskContinuation.cs:line 163
 at System.Net.Http.HttpClient.<SendAsync>g__Core|83_0(HttpRequestMessage, HttpCompletionOption, CancellationTokenSource, Boolean, CancellationTokenSource, CancellationToken) in /runtime/src/libraries/System.Net.Http/src/System/Net/Http/HttpClient.cs:line 544
 --- End of inner exception stack trace ---
 at System.Net.Http.HttpClient.HandleFailure(Exception, Boolean, HttpResponseMessage, CancellationTokenSource, CancellationToken, CancellationTokenSource) in /runtime/src/libraries/System.Net.Http/src/System/Net/Http/HttpClient.cs:line 644
 at System.Net.Http.HttpClient.<SendAsync>g__Core|83_0(HttpRequestMessage, HttpCompletionOption, CancellationTokenSource, Boolean, CancellationTokenSource, CancellationToken) in /runtime/src/libraries/System.Net.Http/src/System/Net/Http/HttpClient.cs:line 564
--- End of stack trace from previous location ---
 at Xunit.Assert.<RecordExceptionAsync>d__215.MoveNext() in /_/src/arcade/src/Microsoft.DotNet.XUnitAssert/src/Record.cs:line 139
===== OperationCanceledException_WithOriginalCancellationToken END exceptionText =====
===== OperationCanceledException_UnknownCancellationToken BEGIN exceptionText =====
System.Threading.Tasks.TaskCanceledException: Useful information
 ---> System.OperationCanceledException: Useful information
 ---> System.Exception: Useful inner exception information
 --- End of inner exception stack trace ---
 at System.Net.Http.Functional.Tests.HttpClientTest.HttpClientSendTest.<Send_InnerHandlerThrows_OriginalExceptionInformationIsCaptured>g__InterestingMethodInTheStackTrace|6_1(Func`1 exceptionFactory) in /runtime/src/libraries/System.Net.Http/tests/FunctionalTests/HttpClientTest.cs:line 1639
 at System.Net.Http.Functional.Tests.HttpClientTest.HttpClientSendTest.<>c__DisplayClass6_0.<Send_InnerHandlerThrows_OriginalExceptionInformationIsCaptured>b__0(HttpRequestMessage, CancellationToken) in /runtime/src/libraries/System.Net.Http/tests/FunctionalTests/HttpClientTest.cs:line 1601
--- End of stack trace from previous location ---
 at System.Runtime.CompilerServices.RuntimeAsyncTaskContinuation.GetResult[T](Task, Byte&) in /runtime/src/coreclr/System.Private.CoreLib/src/System/Runtime/CompilerServices/RuntimeAsyncTaskContinuation.cs:line 140
 at System.Runtime.CompilerServices.RuntimeAsyncTaskContinuation.TaskContinuationResume.ResumeTaskContinuation(Continuation, Byte&) in /runtime/src/coreclr/System.Private.CoreLib/src/System/Runtime/CompilerServices/RuntimeAsyncTaskContinuation.cs:line 163
 at System.Net.Http.HttpClient.<SendAsync>g__Core|83_0(HttpRequestMessage, HttpCompletionOption, CancellationTokenSource, Boolean, CancellationTokenSource, CancellationToken) in /runtime/src/libraries/System.Net.Http/src/System/Net/Http/HttpClient.cs:line 544
 --- End of inner exception stack trace ---
 at System.Net.Http.HttpClient.HandleFailure(Exception, Boolean, HttpResponseMessage, CancellationTokenSource, CancellationToken, CancellationTokenSource) in /runtime/src/libraries/System.Net.Http/src/System/Net/Http/HttpClient.cs:line 644
 at System.Net.Http.HttpClient.<SendAsync>g__Core|83_0(HttpRequestMessage, HttpCompletionOption, CancellationTokenSource, Boolean, CancellationTokenSource, CancellationToken) in /runtime/src/libraries/System.Net.Http/src/System/Net/Http/HttpClient.cs:line 564
--- End of stack trace from previous location ---
 at Xunit.Assert.<RecordExceptionAsync>d__215.MoveNext() in /_/src/arcade/src/Microsoft.DotNet.XUnitAssert/src/Record.cs:line 139
===== OperationCanceledException_UnknownCancellationToken END exceptionText =====
===== HttpRequestException BEGIN exceptionText =====
System.Net.Http.HttpRequestException: Useful information
 ---> System.Exception: Useful inner exception information
 --- End of inner exception stack trace ---
 at System.Net.Http.Functional.Tests.HttpClientTest.HttpClientSendTest.<Send_InnerHandlerThrows_OriginalExceptionInformationIsCaptured>g__InterestingMethodInTheStackTrace|6_1(Func`1 exceptionFactory) in /runtime/src/libraries/System.Net.Http/tests/FunctionalTests/HttpClientTest.cs:line 1639
 at System.Net.Http.Functional.Tests.HttpClientTest.HttpClientSendTest.<>c__DisplayClass6_0.<Send_InnerHandlerThrows_OriginalExceptionInformationIsCaptured>b__0(HttpRequestMessage, CancellationToken) in /runtime/src/libraries/System.Net.Http/tests/FunctionalTests/HttpClientTest.cs:line 1607
 at System.Net.Http.Functional.Tests.HttpClientTest.HttpClientSendTest.<>c__DisplayClass6_0.<Send_InnerHandlerThrows_OriginalExceptionInformationIsCaptured>b__0(HttpRequestMessage _, CancellationToken cancellationToken)
--- End of stack trace from previous location ---
 at System.Net.Http.HttpClient.<SendAsync>g__Core|83_0(HttpRequestMessage, HttpCompletionOption, CancellationTokenSource, Boolean, CancellationTokenSource, CancellationToken) in /runtime/src/libraries/System.Net.Http/src/System/Net/Http/HttpClient.cs:line 544
--- End of stack trace from previous location ---
 at Xunit.Assert.<RecordExceptionAsync>d__215.MoveNext() in /_/src/arcade/src/Microsoft.DotNet.XUnitAssert/src/Record.cs:line 139
===== HttpRequestException END exceptionText =====
===== HttpRequestException_DuringCancellation BEGIN exceptionText =====
System.Threading.Tasks.TaskCanceledException: The operation was canceled.
 ---> System.Net.Http.HttpRequestException: Useful information
 ---> System.Exception: Useful inner exception information
 --- End of inner exception stack trace ---
 at System.Net.Http.Functional.Tests.HttpClientTest.HttpClientSendTest.<Send_InnerHandlerThrows_OriginalExceptionInformationIsCaptured>g__InterestingMethodInTheStackTrace|6_1(Func`1 exceptionFactory) in /runtime/src/libraries/System.Net.Http/tests/FunctionalTests/HttpClientTest.cs:line 1639
 at System.Net.Http.Functional.Tests.HttpClientTest.HttpClientSendTest.<>c__DisplayClass6_0.<Send_InnerHandlerThrows_OriginalExceptionInformationIsCaptured>b__0(HttpRequestMessage, CancellationToken) in /runtime/src/libraries/System.Net.Http/tests/FunctionalTests/HttpClientTest.cs:line 1607
--- End of stack trace from previous location ---
 at System.Runtime.CompilerServices.RuntimeAsyncTaskContinuation.GetResult[T](Task, Byte&) in /runtime/src/coreclr/System.Private.CoreLib/src/System/Runtime/CompilerServices/RuntimeAsyncTaskContinuation.cs:line 140
 at System.Runtime.CompilerServices.RuntimeAsyncTaskContinuation.TaskContinuationResume.ResumeTaskContinuation(Continuation, Byte&) in /runtime/src/coreclr/System.Private.CoreLib/src/System/Runtime/CompilerServices/RuntimeAsyncTaskContinuation.cs:line 163
 at System.Net.Http.HttpClient.<SendAsync>g__Core|83_0(HttpRequestMessage, HttpCompletionOption, CancellationTokenSource, Boolean, CancellationTokenSource, CancellationToken) in /runtime/src/libraries/System.Net.Http/src/System/Net/Http/HttpClient.cs:line 544
 --- End of inner exception stack trace ---
 at System.Net.Http.HttpClient.HandleFailure(Exception, Boolean, HttpResponseMessage, CancellationTokenSource, CancellationToken, CancellationTokenSource) in /runtime/src/libraries/System.Net.Http/src/System/Net/Http/HttpClient.cs:line 644
 at System.Net.Http.HttpClient.<SendAsync>g__Core|83_0(HttpRequestMessage, HttpCompletionOption, CancellationTokenSource, Boolean, CancellationTokenSource, CancellationToken) in /runtime/src/libraries/System.Net.Http/src/System/Net/Http/HttpClient.cs:line 564
--- End of stack trace from previous location ---
 at Xunit.Assert.<RecordExceptionAsync>d__215.MoveNext() in /_/src/arcade/src/Microsoft.DotNet.XUnitAssert/src/Record.cs:line 139
===== HttpRequestException_DuringCancellation END exceptionText =====
===== UnknownException BEGIN exceptionText =====
System.Exception: Useful information
 ---> System.Exception: Useful inner exception information
 --- End of inner exception stack trace ---
 at System.Net.Http.Functional.Tests.HttpClientTest.HttpClientSendTest.<Send_InnerHandlerThrows_OriginalExceptionInformationIsCaptured>g__InterestingMethodInTheStackTrace|6_1(Func`1 exceptionFactory) in /runtime/src/libraries/System.Net.Http/tests/FunctionalTests/HttpClientTest.cs:line 1639
 at System.Net.Http.Functional.Tests.HttpClientTest.HttpClientSendTest.<>c__DisplayClass6_0.<Send_InnerHandlerThrows_OriginalExceptionInformationIsCaptured>b__0(HttpRequestMessage, CancellationToken) in /runtime/src/libraries/System.Net.Http/tests/FunctionalTests/HttpClientTest.cs:line 1613
 at System.Net.Http.Functional.Tests.HttpClientTest.HttpClientSendTest.<>c__DisplayClass6_0.<Send_InnerHandlerThrows_OriginalExceptionInformationIsCaptured>b__0(HttpRequestMessage _, CancellationToken cancellationToken)
--- End of stack trace from previous location ---
 at System.Net.Http.HttpClient.<SendAsync>g__Core|83_0(HttpRequestMessage, HttpCompletionOption, CancellationTokenSource, Boolean, CancellationTokenSource, CancellationToken) in /runtime/src/libraries/System.Net.Http/src/System/Net/Http/HttpClient.cs:line 544
--- End of stack trace from previous location ---
 at Xunit.Assert.<RecordExceptionAsync>d__215.MoveNext() in /_/src/arcade/src/Microsoft.DotNet.XUnitAssert/src/Record.cs:line 139
===== UnknownException END exceptionText =====
===== UnknownException_DuringCancellation BEGIN exceptionText =====
System.Exception: Useful information
 ---> System.Exception: Useful inner exception information
 --- End of inner exception stack trace ---
 at System.Net.Http.Functional.Tests.HttpClientTest.HttpClientSendTest.<Send_InnerHandlerThrows_OriginalExceptionInformationIsCaptured>g__InterestingMethodInTheStackTrace|6_1(Func`1 exceptionFactory) in /runtime/src/libraries/System.Net.Http/tests/FunctionalTests/HttpClientTest.cs:line 1639
 at System.Net.Http.Functional.Tests.HttpClientTest.HttpClientSendTest.<>c__DisplayClass6_0.<Send_InnerHandlerThrows_OriginalExceptionInformationIsCaptured>b__0(HttpRequestMessage, CancellationToken) in /runtime/src/libraries/System.Net.Http/tests/FunctionalTests/HttpClientTest.cs:line 1613
--- End of stack trace from previous location ---
 at System.Runtime.CompilerServices.RuntimeAsyncTaskContinuation.GetResult[T](Task, Byte&) in /runtime/src/coreclr/System.Private.CoreLib/src/System/Runtime/CompilerServices/RuntimeAsyncTaskContinuation.cs:line 140
 at System.Runtime.CompilerServices.RuntimeAsyncTaskContinuation.TaskContinuationResume.ResumeTaskContinuation(Continuation, Byte&) in /runtime/src/coreclr/System.Private.CoreLib/src/System/Runtime/CompilerServices/RuntimeAsyncTaskContinuation.cs:line 163
 at System.Net.Http.HttpClient.<SendAsync>g__Core|83_0(HttpRequestMessage, HttpCompletionOption, CancellationTokenSource, Boolean, CancellationTokenSource, CancellationToken) in /runtime/src/libraries/System.Net.Http/src/System/Net/Http/HttpClient.cs:line 544
--- End of stack trace from previous location ---
 at Xunit.Assert.<RecordExceptionAsync>d__215.MoveNext() in /_/src/arcade/src/Microsoft.DotNet.XUnitAssert/src/Record.cs:line 139
===== UnknownException_DuringCancellation END exceptionText =====
Finished System.Net.Http.Functional.Tests, Version=11.0.0.0, Culture=neutral, PublicKeyToken=cc7b13ffcd2ddd51

Tests run: 6, Errors: 0, Failures: 0, Skipped: 0. Time: 0.2227099s

note I had that debug line in this build as well:

--- a/src/libraries/System.Net.Http/tests/FunctionalTests/HttpClientTest.cs
+++ b/src/libraries/System.Net.Http/tests/FunctionalTests/HttpClientTest.cs
@@ -1629,6 +1629,8 @@ or ExceptionScenario.HttpRequestException_DuringCancellation
 
 string exceptionText = ex.ToString();
 
+ Console.WriteLine($"===== {scenario} BEGIN exceptionText =====\n{exceptionText}\n===== {scenario} END exceptionText =====");
+
 Assert.Contains(InterestingExceptionMessage, exceptionText);
 Assert.Contains(InterestingInnerExceptionMessage, exceptionText);
 Assert.Contains(nameof(InterestingMethodInTheStackTrace), exceptionText);