[ci-scan] Test failure: GC/API/GC/Collect_Aggressive_LargePages on NativeAOT windows-x64

[github-actions]

Build Information

Build: https://dev.azure.com/dnceng-public/public/_build/results?buildId=1521210
Pipeline: runtime-nativeaot-outerloop (definition 265), branch main
Failing leg: NativeAOT_Pri1 on windows-x64
Failing test: GC/API/GC/Collect_Aggressive_LargePages/Collect_Aggressive_LargePages.cmd

Error Message

The test exits with a crash (Actual: -1) instead of the expected pass code under the NativeAOT windows-x64 outer-loop leg:

Running test: GC\API\GC\Collect_Aggressive_LargePages\Collect_Aggressive_LargePages.cmd
Expected: 100
Actual: -1
END EXECUTION - FAILED
Failed test: GC\API\GC\Collect_Aggressive_LargePages\Collect_Aggressive_LargePages.cmd

{
  "ErrorMessage": "Failed test: GC\\API\\GC\\Collect_Aggressive_LargePages\\Collect_Aggressive_LargePages.cmd",
  "BuildRetry": false,
  "ExcludeConsoleLog": false
}

Occurrences

Stable across the scanned window: source build 1521210, follow-up build 1522302, and prior build 1520338 all reproduce this signature on the NativeAOT windows-x64 leg.

First build it occurred: 1520338 (oldest build in scanned window still showing this signature; true origin may predate it).

Related: #130211, #130302, #130432 — same test Collect_Aggressive_LargePages, but distinct signatures (linux SIGSEGV exit 139, linux OOM 0x8007000E exit 255, and a CoreCLR GCCoop regex respectively). This KBE covers the NativeAOT windows-x64 Actual: -1 crash manifestation, which none of those match.

---

Filed by ci-failure-scan; mitigation is tracked by ci-failure-fix.

Note

This issue was generated by an AI agent (GitHub Copilot). Please review for accuracy.

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Generated by CI Outer-Loop Failure Scanner · 992.5 AIC · ⌖ 15.3 AIC · ⊞ 18.6K · ◷

Report

Build	Repository	Test	Pull Request
1528853	dotnet/runtime	GC\API\GC\Collect_Aggressive_LargePages\Collect_Aggressive_LargePages.cmd
1527789	dotnet/runtime	GC\API\GC\Collect_Aggressive_LargePages\Collect_Aggressive_LargePages.cmd
1527340	dotnet/runtime	GC\API\GC\Collect_Aggressive_LargePages\Collect_Aggressive_LargePages.cmd
1527017	dotnet/runtime	GC\API\GC\Collect_Aggressive_LargePages\Collect_Aggressive_LargePages.cmd
1526686	dotnet/runtime	GC\API\GC\Collect_Aggressive_LargePages\Collect_Aggressive_LargePages.cmd
1526411	dotnet/runtime	GC\API\GC\Collect_Aggressive_LargePages\Collect_Aggressive_LargePages.cmd
1525821	dotnet/runtime	GC\API\GC\Collect_Aggressive_LargePages\Collect_Aggressive_LargePages.cmd
1524187	dotnet/runtime	GC\API\GC\Collect_Aggressive_LargePages\Collect_Aggressive_LargePages.cmd
1523819	dotnet/runtime	GC\API\GC\Collect_Aggressive_LargePages\Collect_Aggressive_LargePages.cmd
1523325	dotnet/runtime	GC\API\GC\Collect_Aggressive_LargePages\Collect_Aggressive_LargePages.cmd
1523104	dotnet/runtime	GC\API\GC\Collect_Aggressive_LargePages\Collect_Aggressive_LargePages.cmd

Summary

24-Hour Hit Count	7-Day Hit Count	1-Month Count
0	11	11

[dotnet-policy-service]

Tagging subscribers to this area: @anicka-net, @dotnet/gc
See info in area-owners.md if you want to be subscribed.

[github-actions]

Workflow artifact: ci-fix
Artifact kind: handoff
Linked KBE: #131262

Note

AI/Copilot-generated triage note.

This Known Build Error has no producible automated code change (reason: GC/runtime crash — must not be auto-fixed), 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)

GC/API/GC/Collect_Aggressive_LargePages crashes on the runtime-nativeaot-outerloop windows-x64 NativeAOT_Pri1 leg, exiting with Actual: -1 (process crash) instead of the expected 100:

Running test: GC\API\GC\Collect_Aggressive_LargePages\Collect_Aggressive_LargePages.cmd
Expected: 100
Actual: -1
END EXECUTION - FAILED

The test (src/tests/GC/API/GC/Collect_Aggressive_LargePages.cs) is a regression test for #126903: several writer threads churn a ConcurrentDictionary<int, byte[]> while a GC thread repeatedly calls GC.Collect(2, GCCollectionMode.Aggressive, blocking: true, compacting: true) under emulated large pages (DOTNET_GCLargePages=2). Rather than a controlled test-assert failure (return 101), the process itself crashes (-1), which points at a GC/runtime fault in the aggressive-collect + compacting path under NativeAOT on windows-x64, not a test-logic bug. Because the symptom is a native crash in GC codegen/runtime, there is no safe small source change this workflow can make.

This is a distinct signature from the sibling KBEs on the same test (#130211 linux SIGSEGV exit 139, #130302 linux OOM 0x8007000E), so it should be tracked and fixed on its own on the NativeAOT windows-x64 GC path.

Evidence

• Failing build: https://dev.azure.com/dnceng-public/public/_build/results?buildId=1521210 (runtime-nativeaot-outerloop, 20260722.2, result=failed)
• First build it occurred: 1520338 (oldest build in scanned window still showing this signature; true origin may predate it)
• Possible related PR: none identified with sufficient confidence

Suggested reviewers / area contacts

• Area owners (area-GC-coreclr): @anicka-net, @dotnet/gc

A fix would likely involve diagnosing the NativeAOT windows-x64 crash in the aggressive/compacting GC path under emulated large pages (DOTNET_GCLargePages=2); a local repro under NativeAOT windows-x64 with the env var set should reproduce the crash for debugging.

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:
  allowed:
    - defaults
    - "awmgmcpg"

See Network Configuration for more information.

Generated by CI Outer-Loop Failure Fixer · 285.1 AIC · ⌖ 17 AIC · ⊞ 17.1K · ◷