[ci-scan] Hang: maccatalyst-arm64 AllSubsets_CoreCLR_RuntimeTests time out (Test run never launched) on osx.26.arm64

[github-actions]

Build Information

Build: https://dev.azure.com/dnceng-public/public/_build/results?buildId=1584171
Build error leg or test failing: maccatalyst-arm64 Release AllSubsets_CoreCLR_RuntimeTests - osx.26.arm64.open — CoreCLR runtime test work items (Exceptions, Interop, jit64_3, Methodical_*, threading_group2, Regression_PdbOnly_r_1)

KBE authoring guidance (ci-failure-scan)

• Error Details is for readers. Paste the full exception, stack trace, or build error excerpt so the failure is understandable without opening the raw log.
• Build Analysis parses only the single JSON block under Error Message.
• ErrorMessage is a case-sensitive ordinal String.Contains substring copied verbatim from the failing log.
• Set BuildRetry to true only for a clear infrastructure retry case. ExcludeConsoleLog disables Helix console-log scanning.

Error Details

On the runtime-extra-platforms pipeline (definition 154), the maccatalyst-arm64 Release AllSubsets_CoreCLR_RuntimeTests - osx.26.arm64.open leg fails repeatedly: multiple CoreCLR runtime-test work items never launch the test application and are killed after the 3-hour (10800 second) work-item timeout. The harness reports that the process could never be attached and that the test run never launched, indicating an app-launch/attach failure on the osx.26.arm64 MacCatalyst queue rather than a test assertion.

[03:38:13] fail: Run timed out after 10800 seconds
[03:38:13] dbug: Pids to kill: 25661
[03:38:13] dbug: Running lldb diagnostics for pid 25661
[03:38:14] dbug: (lldb) process attach --pid 25661
[03:38:14] dbug: error: attach failed: no such process
[03:38:14] dbug: 25661 Execution timed out after 10800 seconds and the process was killed.
[03:38:14] dbug: Test run timed out after 180 minute(s).
[03:38:14] dbug: Could not find pid in mtouch output.
[03:38:14] dbug: Test run never launched

Observed across work items in build 1584171 (source) and reproduced in follow-up build 1584749 (Exceptions, Interop, Regression_PdbOnly_r_1, threading_group2), so the failure is stable across builds and work items on this leg.

Error Message

{
  "ErrorMessage": [
    "Run timed out after 10800 seconds",
    "Test run never launched"
  ],
  "ErrorPattern": "",
  "BuildRetry": false,
  "ExcludeConsoleLog": false
}

Agentic workflow metadata (ci-failure-scan)

Workflow artifact: ci-failure-scan
Artifact kind: kbe-verification
Verified match count: both lines present in failure.log for each failed work item; observed across 8 maccatalyst-arm64 RuntimeTests work items in source build 1584171 and reproduced in follow-up 1584749

---

Note

This issue was filed automatically by the ci-failure-scan agentic workflow (AI/Copilot-generated). Mitigation is handled separately by the ci-failure-fix workflow.

Generated by CI Outer-Loop Failure Scanner · opus48 · 814.4 AIC · ⌖ 20 AIC · ⊞ 20.7K · ◷

Report

Build	Repository	Test	Pull Request
1608142	dotnet/runtime	Regression_PdbOnly_r_4.WorkItemExecution
1607380	dotnet/runtime	GC-scenarios1.WorkItemExecution
1606967	dotnet/runtime	tracing.WorkItemExecution
1606626	dotnet/runtime	GC-features.WorkItemExecution
1606616	dotnet/runtime	Regression_o_2.WorkItemExecution
1604459	dotnet/runtime	JIT_r.WorkItemExecution
1603402	dotnet/runtime	Regression_do.WorkItemExecution
1602914	dotnet/runtime	Regression_9.WorkItemExecution	#134060
1602208	dotnet/runtime	JIT.opt.WorkItemExecution
1601987	dotnet/runtime	JIT_ro.WorkItemExecution
1601683	dotnet/runtime	Regression_PdbOnly_ro.WorkItemExecution	#133828
1600403	dotnet/runtime	Regression_2.WorkItemExecution
1598688	dotnet/runtime	Regression_4.WorkItemExecution
1596986	dotnet/runtime	JIT_others.WorkItemExecution
1594919	dotnet/runtime	Methodical_d1.WorkItemExecution
1594486	dotnet/runtime	Loader.WorkItemExecution
1593920	dotnet/runtime	JIT.CodeGenBringUpTests_r.WorkItemExecution
1592042	dotnet/runtime	threading_group2.WorkItemExecution
1590326	dotnet/runtime	jit64_3.WorkItemExecution

Summary

24-Hour Hit Count	7-Day Hit Count	1-Month Count
3	12	19

[dotnet-policy-service]

Tagging subscribers to this area: @dotnet/runtime-infrastructure
See info in area-owners.md if you want to be subscribed.

[github-actions]

Workflow artifact: ci-fix
Artifact kind: handoff
Linked KBE: #133325

Note

AI/Copilot-generated triage note.

This Known Build Error is a non-code/infra failure (test host never launches on the MacCatalyst queue), so there is no producible product diff. Looping in owners rather than muting.

Root cause (best analysis)

On runtime-extra-platforms (def 154), the maccatalyst-arm64 Release AllSubsets_CoreCLR_RuntimeTests - osx.26.arm64.open leg fails across multiple CoreCLR runtime-test work items (Exceptions, Interop, jit64_3, Methodical_*, threading_group2, Regression_PdbOnly_r_1): the test app never launches and each work item is killed after the 3-hour (10800s) timeout. The harness logs process attach --pid ... error: attach failed: no such process, Could not find pid in mtouch output, and Test run never launched. This is an app-launch/attach failure on the osx.26.arm64 MacCatalyst queue (provisioning/launch/simulator or image issue), not a test assertion — an infrastructure/mobile problem with no source fix.

Evidence

• Failing build: https://dev.azure.com/dnceng-public/public/_build/results?buildId=1584171 (reproduces in 1584749)
• First build it occurred: source build 1584171 (within the scanned window; may not be the true origin)
• Possible related PR: none identified with sufficient confidence

Suggested reviewers / area contacts

• Area owners (area-Infrastructure): @agocke, @dotnet/runtime-infrastructure
• Mobile infra (area-Infrastructure-mono): @akoeplinger

A fix likely involves investigating why the MacCatalyst app never launches/attaches on the osx.26.arm64.open Helix queue (queue image, provisioning, or launch harness), since no test code runs.

Structured data:

{
  "artifact_kind": "handoff",
  "linked_kbe": 133325,
  "workflow_artifact": "ci-fix"
}

Generated by CI Outer-Loop Failure Fixer · opus48 · 444.8 AIC · ⌖ 28.9 AIC · ⊞ 19.6K · ◷