Repository navigation
Crash: access violation in coreclr!PgoManager::getPgoInstrumentationResults during tier-1 background JIT (Windows x86) #134695
Description
Build Information
Build: https://dev.azure.com/dnceng-public/public/_build/results?buildId=1613037
Build error leg or test failing: Build windows-x86 release CoreCLR_AllSubsets-System.Private.Xml.Tests
Pull request: #134676
Also seen on main (same frame, Windows x86 Release CoreCLR): Helix jobs 98eb605a-92e7-45bd-91e3-38e51ec14951 (System.Transactions.Local.Tests), 4749098d-8bf3-4bfe-b8fb-7e0f16da0fa0 (System.Collections.Concurrent.Tests), 3fdcb624-6a07-465c-a3de-068849c7ea6f (System.Resources.Extensions.Tests).
KBE authoring guidance (ci-failure-scan)
Error Detailsis 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. ErrorMessageis a case-sensitive ordinalString.Containssubstring copied verbatim from the failing log.- Set
BuildRetrytotrueonly for a clear infrastructure retry case.ExcludeConsoleLogdisables Helix console-log scanning.
Error Details
The test process dies with 0xC0000005 while the tiered-compilation background worker is re-jitting a method at tier 1; the fault is in PgoManager::getPgoInstrumentationResults. The foreground test thread is unrelated (file cleanup in FileCleanupTestBase.Dispose), and the crash has hit many unrelated test assemblies.
(1c90.145c): Access violation - code c0000005 (first/second chance not available)
coreclr!StressLog::InlinedStressLogOn [inlined in coreclr!WatsonLastChance+0x1f6]
coreclr!WatsonLastChance+0x1f6
coreclr!EEPolicy::LogFatalError+0x607
coreclr!EEPolicy::HandleFatalError+0x123
coreclr!CLRVectoredExceptionHandlerPhase3+0xb8bc5
coreclr!CLRVectoredExceptionHandler+0xb1
ntdll!KiUserExceptionDispatcher+0xf
coreclr!PgoManager::getPgoInstrumentationResults+0x87
coreclr!CEECodeGenInfo::getPgoInstrumentationResults+0x180
clrjit!Compiler::compInitOptions+0x38a
clrjit!Compiler::compCompileHelper+0x107
clrjit!jitNativeCode+0x1bb
clrjit!CILJit::compileMethod+0x9b
coreclr!UnsafeJitFunction+0x56a
coreclr!MethodDesc::JitCompileCodeLocked+0x8d
coreclr!MethodDesc::PrepareCode+0x17b
coreclr!TieredCompilationManager::CompileCodeVersion+0x85
coreclr!TieredCompilationManager::OptimizeMethod+0x1a
coreclr!TieredCompilationManager::DoBackgroundWork+0x48e
coreclr!TieredCompilationManager::BackgroundWorkerStart+0xde
['System.Private.Xml.Tests' END OF WORK ITEM LOG: Command exited with -1073741819]
Error Message
{
"ErrorMessage": [
"Access violation - code c0000005",
"coreclr!PgoManager::getPgoInstrumentationResults"
],
"ErrorPattern": "",
"BuildRetry": false,
"ExcludeConsoleLog": false
}Agentic workflow metadata (ci-failure-scan)
Workflow artifact: ci-failure-scan
Artifact kind: kbe-verification
Verified match count: 2 hits in failure.log
Note
This issue was drafted with GitHub Copilot.
Known issue validation
Build: 🔎 https://dev.azure.com/dnceng-public/public/_build/results?buildId=1613037
Error message validated: [Access violation - code c0000005 coreclr!PgoManager::getPgoInstrumentationResults]
Result validation: ✅ Known issue matched with the provided build.
Validation performed at: 9/26/2026 2:23:51 AM UTC
Report
Summary
| 24-Hour Hit Count | 7-Day Hit Count | 1-Month Count |
|---|---|---|
| 0 | 13 | 173 |
Activity
dotnet-policy-service commentedon Sep 26, 2026
Tagging subscribers to this area: @JulieLeeMSFT, @jakobbotsch
See info in area-owners.md if you want to be subscribed.
AndyAyersMS commentedon Nov 2, 2026
Seems like this could be the same issue as in #125699
PGO: make value histograms 32-bit on all targets (dotnet#136895)
lewing commentedon Nov 4, 2026
reopening for release branches