GC BridgeTester test seems to be flaky on 9.0 on mono Windows

[svick]

Build Information

Build: https://dev.azure.com/dnceng-public/cbb18261-c48f-4abb-8651-8cdcb5474649/_build/results?buildId=1475174
Build error leg or test failing: GC\Features\Bridge\BridgeTester\BridgeTester.cmd
Pull request: #129407

Error Message

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Fill the error message using step by step known issues guidance.

{
  "ErrorMessage": "System.Exception: Bridge Test App failed execution",
  "BuildRetry": false,
  "ExcludeConsoleLog": false
}

BEGIN EXECUTION
 "C:\h\w\A0CE08E7\p\corerun.exe" -p "System.Reflection.Metadata.MetadataUpdater.IsSupported=false" -p "System.Runtime.Serialization.EnableUnsafeBinaryFormatterSerialization=true"  BridgeTester.dll 
Start test SetupFragmentation
[6/22/2026 11:10:36 AM] CrashLoop 1/4
[6/22/2026 11:10:36 AM] major fill done
[6/22/2026 11:10:37 AM] fragmentation done
[6/22/2026 11:10:38 AM] done spewing bridges
[6/22/2026 11:10:41 AM] CrashLoop 2/4
[6/22/2026 11:10:43 AM] major fill done
[6/22/2026 11:10:43 AM] fragmentation done
[6/22/2026 11:10:44 AM] done spewing bridges
SCCS count expected 580135 but got 629016
Bridge Test App returned -1073740791
System.Exception: Bridge Test App failed execution
   at BridgeTester.RunTests()
   at __GeneratedMainWrapper.Main()
Expected: 100
Actual: 101
END EXECUTION - FAILED

Known issue validation

Build: 🔎 https://dev.azure.com/dnceng-public/public/_build/results?buildId=1475174
Error message validated: [System.Exception: Bridge Test App failed execution]
Result validation: ✅ Known issue matched with the provided build.
Validation performed at: 6/23/2026 4:31:53 PM UTC

Report

Build	Repository	Test	Pull Request
1475174	dotnet/runtime	PayloadGroup0.WorkItemExecution	#129407

Summary

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

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