[ci-scan] Test failure: JIT/Regression/CLR-x86-JIT/V1-M12-Beta2/b65423 crashes on browser-wasm with `strerror` called after runt [Content truncated due to length]

[github-actions]

Build Information

Build: https://dev.azure.com/dnceng-public/public/_build/results?buildId=1541935
Build error leg or test failing: coreclr Pri1 Runtime Tests Run browser wasm checked - JIT/Regression/CLR-x86-JIT/V1-M12-Beta2/b65423/b65423/b65423.cmd

Error Details

The b65423 JIT regression test fails on the runtime-coreclr outerloop browser-wasm checked leg. After catching the expected TypeLoadException (exit 100), the wasm runtime aborts during shutdown because strerror is invoked after the runtime has exited. The test then reports Expected 100 / Actual 1.

Caught TypeLoadException exception: 100
Aborted(Assertion failed: native function `strerror` called after runtime exit (use NO_EXIT_RUNTIME to keep it alive after main() exits))
(wasm/redacted)

RuntimeError: unreachable
    at abort (corerun.js)
    at assert (corerun.js)
    at strError (corerun.js)
    at new ErrnoError (corerun.js)
    at Object.getStreamChecked (corerun.js)
    at Object.getStreamFromFD (corerun.js)
    at _fd_write (corerun.js)
Expected: 100
Actual: 1
END EXECUTION - FAILED
02:10:36.782 Failed test: JIT/Regression/CLR-x86-JIT/V1-M12-Beta2/b65423/b65423/b65423.cmd

Observed in build 1541935 (2026-08-06) and reproduced in follow-up build 1542249 on the same leg.

Error Message

{
  "ErrorMessage": [
    "Aborted(Assertion failed: native function `strerror` called after runtime exit (use NO_EXIT_RUNTIME to keep it alive after main() exits))",
    "Failed test: JIT/Regression/CLR-x86-JIT/V1-M12-Beta2/b65423/b65423/b65423.cmd"
  ],
  "ErrorPattern": "",
  "BuildRetry": false,
  "ExcludeConsoleLog": false
}

---

Filed by ci-failure-scan (detection only). ci-failure-fix walks open [ci-scan] KBEs and either opens a small fix PR or comments here to loop in owners — it never disables the test.

Note

This issue was generated by an AI agent (ci-failure-scan Copilot workflow).

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Generated by CI Outer-Loop Failure Scanner · 554.9 AIC · ⌖ 12.2 AIC · ⊞ 18.3K · ◷

Report

Build	Repository	Test	Pull Request
1546439	dotnet/runtime	JIT/Regression/CLR-x86-JIT/V1-M12-Beta2/b65423/b65423/b65423.cmd
1546024	dotnet/runtime	JIT/Regression/CLR-x86-JIT/V1-M12-Beta2/b65423/b65423/b65423.cmd
1545892	dotnet/runtime	JIT/Regression/CLR-x86-JIT/V1-M12-Beta2/b65423/b65423/b65423.cmd
1545742	dotnet/runtime	JIT/Regression/CLR-x86-JIT/V1-M12-Beta2/b65423/b65423/b65423.cmd
1545609	dotnet/runtime	JIT/Regression/CLR-x86-JIT/V1-M12-Beta2/b65423/b65423/b65423.cmd
1545482	dotnet/runtime	JIT/Regression/CLR-x86-JIT/V1-M12-Beta2/b65423/b65423/b65423.cmd
1545348	dotnet/runtime	JIT/Regression/CLR-x86-JIT/V1-M12-Beta2/b65423/b65423/b65423.cmd
1545184	dotnet/runtime	JIT/Regression/CLR-x86-JIT/V1-M12-Beta2/b65423/b65423/b65423.cmd
1544819	dotnet/runtime	JIT/Regression/CLR-x86-JIT/V1-M12-Beta2/b65423/b65423/b65423.cmd
1544116	dotnet/runtime	JIT/Regression/CLR-x86-JIT/V1-M12-Beta2/b65423/b65423/b65423.cmd
1543631	dotnet/runtime	JIT/Regression/CLR-x86-JIT/V1-M12-Beta2/b65423/b65423/b65423.cmd
1543347	dotnet/runtime	JIT/Regression/CLR-x86-JIT/V1-M12-Beta2/b65423/b65423/b65423.cmd	#131866
1543091	dotnet/runtime	JIT/Regression/CLR-x86-JIT/V1-M12-Beta2/b65423/b65423/b65423.cmd
1541935	dotnet/runtime	JIT/Regression/CLR-x86-JIT/V1-M12-Beta2/b65423/b65423/b65423.cmd

Summary

24-Hour Hit Count	7-Day Hit Count	1-Month Count
3	14	14

[dotnet-policy-service]

Tagging subscribers to this area: @JulieLeeMSFT, @jakobbotsch
See info in area-owners.md if you want to be subscribed.

[dotnet-policy-service]

Tagging subscribers to 'arch-wasm': @lewing, @pavelsavara
See info in area-owners.md if you want to be subscribed.

[JulieLeeMSFT]

@pavelsavara, PTAL.
cc @dotnet/wasm-contrib.

[github-actions]

Workflow artifact: ci-fix
Artifact kind: handoff
Linked KBE: #131937

Note

AI/Copilot-generated triage note.

This Known Build Error has no producible automated code change (reason: non-code/infra failure in the wasm runtime shutdown path — not something I can correct with a small, safe source diff, and the only test-side "fix" would be to disable the test, which this workflow must never do), so I could not open even a best-effort PR. Looping in owners so it can be fixed forward rather than muted.

Root cause (best analysis)

On the runtime-coreclr outerloop browser-wasm checked leg, JIT/Regression/CLR-x86-JIT/V1-M12-Beta2/b65423 catches its expected TypeLoadException (which is the intended Expected: 100 result), but the wasm runtime then aborts during shutdown:

Caught TypeLoadException exception: 100
Aborted(Assertion failed: native function `strerror` called after runtime exit
        (use NO_EXIT_RUNTIME to keep it alive after main() exits))
   ... at _fd_write (corerun.js)
Expected: 100
Actual: 1

The test logic itself passes; the failure is that an Emscripten strerror/_fd_write call (a flush of stdout/stderr) runs after main() has returned and the runtime has exited, tripping the "called after runtime exit" assertion and turning exit code 100 into 1. This is a wasm host/shutdown ordering issue (a late fd_write on a torn-down runtime), not a JIT codegen defect and not a defect in the test body — so no source-level test change is appropriate, and disabling the test is out of scope for this workflow.

Evidence

• Failing build: https://dev.azure.com/dnceng-public/public/_build/results?buildId=1541935 (leg: coreclr Pri1 browser-wasm checked)
• Reproduces in follow-up build 1542249 on the same leg.
• Possible related PR: none identified with sufficient confidence.

Suggested reviewers / area contacts

• Area owners (arch-wasm): @lewing, @pavelsavara

A fix would likely involve keeping the wasm runtime alive long enough to flush stdio during shutdown (e.g. the NO_EXIT_RUNTIME / late-fd_write handling in the CoreCLR wasm host corerun.js glue), so the post-exit strerror assertion no longer fires after a passing test.

Warning

Firewall blocked 1 domain

The following domain was blocked by the firewall during workflow execution:

• awmgmcpg

To allow these domains, add them to the network.allowed list in your workflow frontmatter:

network:
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    - "awmgmcpg"

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Generated by CI Outer-Loop Failure Fixer · 400.7 AIC · ⌖ 18.4 AIC · ⊞ 17.1K · ◷