Test Failure: _simple_eh::Async2SimpleEH.TestThrowAfterYield()

[JulieLeeMSFT]

Summary:
Async exception handling test Async2SimpleEH.TestThrowAfterYield returns 0 instead of expected 42.
Fails on ALL pri1 tests (linux arm64, linux x64, windows x64, windows arm64, osx x64, osx arm64) under all jitpartialcompilation configs. High impact regression since 2026-02-07.

Failed in:

• runtime-jit-experimental 20260303.1

Failed tests:

- coreclr linux arm64 Checked jitpartialcompilation_pgo @ AzureLinux.3.Arm64.Open
- coreclr linux arm64 Checked jitpartialcompilation_pgo_stress_random @ AzureLinux.3.Arm64.Open
- coreclr linux arm64 Checked jitpartialcompilation @ AzureLinux.3.Arm64.Open
- coreclr linux x64 Checked jitpartialcompilation_pgo_stress_random @ AzureLinux.3.Amd64.Open
- coreclr linux x64 Checked jitpartialcompilation @ AzureLinux.3.Amd64.Open
- coreclr linux x64 Checked jitpartialcompilation_pgo @ AzureLinux.3.Amd64.Open
- coreclr windows x64 Checked jitpartialcompilation_pgo_stress_random @ Windows.10.Amd64.Open
- coreclr windows x64 Checked jitpartialcompilation_pgo @ Windows.10.Amd64.Open
- coreclr windows x64 Checked jitpartialcompilation @ Windows.10.Amd64.Open
- coreclr windows arm64 Checked jitpartialcompilation_pgo_stress_random @ Windows.11.Arm64.Open
- coreclr windows arm64 Checked jitpartialcompilation_pgo @ Windows.11.Arm64.Open
- coreclr osx x64 Checked jitpartialcompilation_pgo_stress_random @ OSX.15.Amd64.Open
- coreclr osx x64 Checked jitpartialcompilation @ OSX.15.Amd64.Open
- coreclr osx x64 Checked jitpartialcompilation_pgo @ OSX.15.Amd64.Open
- coreclr osx arm64 Checked jitpartialcompilation @ OSX.26.Arm64.Open
- coreclr osx arm64 Checked jitpartialcompilation_pgo @ OSX.26.Arm64.Open
  - _simple_eh::Async2SimpleEH.TestThrowAfterYield()

Error Message:

System.AggregateException: One or more errors occurred. (Assert.Equal() Failure: Values differ
Expected: 42
Actual:   0

Stack Trace:

Assert.Equal() Failure
Expected: 42
Actual:   0
  at Async2SimpleEH.TestThrowAfterYield()

[JulieLeeMSFT]

@jakobbotsch, PTAL.

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