[ci-scan] Build break: Mono FullAOT recursive type definition in JIT.Generics_ro (chaos65204782cs)

[github-actions]

Build Information

Build: https://dev.azure.com/dnceng-public/public/_build/results?buildId=1560207
Build error leg or test failing: linux-x64 Release AllSubsets_Mono_MiniFullAot_RuntimeTests minifullaot - AOT compile CoreCLR tests (JIT.Generics_ro)

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

The Mono FullAOT compile step (aot-compile.proj) fails while AOT-compiling JIT.Generics_ro.dll. The Mono AOT compiler emits over a thousand Failed to load methodspec errors rooted in a recursive generic type definition, then the MSBuild Exec fails:

EXEC : Failed to load methodspec 0x2b0003fa due to Could not find method 'VerifyA0A1A2A3NotInlinedGenericStatic' due to a type load error : Could not set up parent class, due to: Generic Type Definition failed to init, due to: Could not set up parent class, due to: Generic Type Definition failed to init, due to: Recursive type definition detected JitTest_Generics_Coverage_chaos65204782cs.A0A1`1 ... type:A0A1A2A3`2 member:(null). [/src/mono/msbuild/aot-compile.proj]
/src/mono/msbuild/aot-compile.proj(19,9): error MSB3077: The command "corerun .../JIT/Generics/JIT.Generics_ro/JIT.Generics_ro.dll" exited with return value 0, but errors were detected during execution. ExitCode was set to -1.
    1154 Error(s)
Build failed with exit code 1. Check errors above.

First observed in build 1560207 (2026-08-20, linux-x64 minifullaot); still failing in follow-up build 1561700 (2026-08-21). First build it occurred: 1558665 (2026-08-19); build 1556608 (2026-08-18) did not contain this signature.

Error Message

{
  "ErrorMessage": "Recursive type definition detected JitTest_Generics_Coverage_chaos65204782cs.A0A1`1",
  "ErrorPattern": "",
  "BuildRetry": false,
  "ExcludeConsoleLog": false
}

Agentic workflow metadata (ci-failure-scan)

Workflow artifact: ci-failure-scan
Artifact kind: kbe-verification
Verified match count: 768 hits in failure.log

---

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 GitHub Copilot workflow).

Generated by CI Outer-Loop Failure Scanner · opus48 · 596.1 AIC · ⌖ 17.9 AIC · ⊞ 20.7K · ◷

Report

Build	Repository	Step Name	Console log	Pull Request
1563727	dotnet/runtime	AOT compile CoreCLR tests	Log
1563501	dotnet/runtime	AOT compile CoreCLR tests	Log
1563399	dotnet/runtime	AOT compile CoreCLR tests	Log
1563009	dotnet/runtime	AOT compile CoreCLR tests	Log

Summary

24-Hour Hit Count	7-Day Hit Count	1-Month Count
2	4	4