[ci-scan] Build break: crossgen2-comparison hash mismatch on windows x86 (recurrence)

[github-actions]

Build Information

Build: https://dev.azure.com/dnceng-public/public/_build/results?buildId=1470127
Build error leg or test failing: Test crossgen2-comparison windows x86 Release to x86 windows - WorkItem

Error Details

crossgen2_comparison.py detects non-deterministic R2R image output when crossgen2 compiles assemblies twice targeting windows-x86. 4 of 236 compared assemblies produce different SHA-256 hashes between the baseline and re-compilation pass.

File hash sum mismatch for "System.Data.Odbc" assembly for files of type "NativeOrReadyToRunImage":
File hash sum mismatch for "System.IO.Compression" assembly for files of type "NativeOrReadyToRunImage":
File hash sum mismatch for "System.Private.CoreLib" assembly for files of type "NativeOrReadyToRunImage":
File hash sum mismatch for "System.Runtime.Numerics" assembly for files of type "NativeOrReadyToRunImage":
Number of mismatched results: 4

Affected pipelines:

• runtime-coreclr crossgen2 outerloop (def 134): Test crossgen2-comparison windows x86 Release to x86 windows

Error Message

{
  "ErrorMessage": ["File hash sum mismatch for", "NativeOrReadyToRunImage"],
  "ErrorPattern": "",
  "BuildRetry": false,
  "ExcludeConsoleLog": false
}

First build it occurred

• Persistent across 10+ consecutive builds (earliest scanned: 1455403, 2026-06-09).
• True origin may predate 2026-06-09.
• Confirmed in follow-up: https://dev.azure.com/dnceng-public/public/_build/results?buildId=1470127

Predecessor / related issues

• [ci-scan] Build break: crossgen2 comparison NativeOrReadyToRunImage hash mismatch on linux arm #129013 (closed 2026-06-05, linux-arm variant; same root cause family)
• crossgen2-comparison windows x86 Release to x86 windows failing for System.Private.CoreLib #115661 (closed 2025-07-23, previously fixed for System.Private.CoreLib only)
• Crossgen2 comparisons are failing in coreclr-outerloop runs #111972 (closed, historical crossgen2 comparison failures)

Duplicate search

• "File hash sum mismatch" crossgen2 is:open label:"Known Build Error" — 0 results
• "CrossgenCompile" "crossgen2-comparison" is:open label:"Known Build Error" — 0 results
• "hash sum mismatch" is:open — 0 results
• Recently-closed: [ci-scan] Build break: crossgen2 comparison NativeOrReadyToRunImage hash mismatch on linux arm #129013 (closed Jun 5, was linux-arm specific; windows-x86 is a distinct occurrence)

---

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.

Warning

Firewall blocked 1 domain

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

• dotnet.github.io

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

network:
  allowed:
    - defaults
    - "dotnet.github.io"

See Network Configuration for more information.

Note

🔒 Integrity filter blocked 13 items

The following items were blocked because they don't meet the GitHub integrity level.

• #92420 search_issues: has lower integrity than agent requires. The agent cannot read data with integrity below "approved".
• #110173 search_issues: has lower integrity than agent requires. The agent cannot read data with integrity below "approved".
• #83659 search_issues: has lower integrity than agent requires. The agent cannot read data with integrity below "approved".
• #116060 search_issues: has lower integrity than agent requires. The agent cannot read data with integrity below "approved".
• #105441 search_issues: has lower integrity than agent requires. The agent cannot read data with integrity below "approved".
• #111922 search_issues: has lower integrity than agent requires. The agent cannot read data with integrity below "approved".
• #106113 search_issues: has lower integrity than agent requires. The agent cannot read data with integrity below "approved".
• #105443 search_issues: has lower integrity than agent requires. The agent cannot read data with integrity below "approved".
• #94393 search_issues: has lower integrity than agent requires. The agent cannot read data with integrity below "approved".
• #89545 search_issues: has lower integrity than agent requires. The agent cannot read data with integrity below "approved".
• #92468 search_issues: has lower integrity than agent requires. The agent cannot read data with integrity below "approved".
• #82637 search_issues: has lower integrity than agent requires. The agent cannot read data with integrity below "approved".
• #84394 search_issues: has lower integrity than agent requires. The agent cannot read data with integrity below "approved".

To allow these resources, lower min-integrity in your GitHub frontmatter:

tools:
  github:
    min-integrity: approved  # merged | approved | unapproved | none

Generated by CI Outer-Loop Failure Scanner · ● 131.8M · ◷

Report

Build	Repository	Test	Pull Request
1474866	dotnet/runtime	CrossgenCompile_System.Runtime.Numerics_Target_windows_x86_windows_x64_vs_windows_x86
1474193	dotnet/runtime	CrossgenCompile_System.Runtime.Numerics_Target_windows_x86_windows_x64_vs_windows_x86
1473755	dotnet/runtime	CrossgenCompile_System.Runtime.Numerics_Target_windows_x86_windows_x64_vs_windows_x86	#129285
1473655	dotnet/runtime	CrossgenCompile_System.Data.Odbc_Target_windows_x86_windows_x64_vs_windows_x86
1472229	dotnet/runtime	CrossgenCompile_System.IO.Compression_Target_windows_x86_windows_x64_vs_windows_x86	#129285
1471956	dotnet/runtime	CrossgenCompile_System.Data.Odbc_Target_windows_x86_windows_x64_vs_windows_x86

Summary

24-Hour Hit Count	7-Day Hit Count	1-Month Count
1	6	6