Flaky test failure: msbuild.binlog file lock (IOException: being used by another process)

[Evangelink]

Build Information

Build: https://dev.azure.com/dnceng-public/cbb18261-c48f-4abb-8651-8cdcb5474649/_build/results?buildId=1467980
Build error leg or test failing: Various tests (file lock on msbuild.binlog during test execution)
Pull request: #54729

Error Message

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

{
  "ErrorMessage": "",
  "ErrorPattern": "System\\.IO\\.IOException : The process cannot access the file '.*msbuild\\.binlog' because it is being used by another process\\.",
  "BuildRetry": true,
  "ExcludeConsoleLog": false
}

Details

Error message

System.IO.IOException : The process cannot access the file '/datadisks/disk1/work/AA09096E/w/AEB00993/uploads/AEB00993-e-msbuild.binlog' because it is being used by another process.

Stack trace

at Microsoft.Win32.SafeHandles.SafeFileHandle.Open(String fullPath, FileMode mode, FileAccess access, FileShare share, FileOptions options, Int64 preallocationSize, UnixFileMode openPermissions, Int64& fileLength, UnixFileMode& filePermissions, Boolean failForSymlink, Boolean& wasSymlink, Func`4 createOpenException)
   at System.IO.File.Copy(String sourceFileName, String destFileName, Boolean overwrite)
   at Microsoft.NET.TestFramework.Commands.TestCommand.Execute(IEnumerable`1 args) in /_/test/Microsoft.NET.TestFramework/Commands/TestCommand.cs:line 227
   at Microsoft.DotNet.Cli.Utils.ExponentialRetry.ExecuteAsyncWithRetry[T](Func`1 action, Func`2 shouldStopRetry, Int32 maxRetryCount, Func`1 timer, String taskDescription) in /_/src/Cli/Microsoft.DotNet.Cli.Utils/ExponentialRetry.cs:line 46
   at Microsoft.DotNet.Cli.Utils.ExponentialRetry.ExecuteWithRetry[T](Func`1 action, Func`2 shouldStopRetry, Int32 maxRetryCount, Func`1 timer, String taskDescription) in /_/src/Cli/Microsoft.DotNet.Cli.Utils/ExponentialRetry.cs:line 68
   at Microsoft.NET.TestFramework.Commands.TestCommand.Execute(String[] args) in /_/test/Microsoft.NET.TestFramework/Commands/TestCommand.cs:line 147
   at Microsoft.NET.Publish.Tests.GivenThatWeWantToRunILLink1.ILLink_links_simple_app_without_analysis_warnings_and_it_runs(String targetFramework) in /_/test/Microsoft.NET.Publish.Tests/GivenThatWeWantToRunILLink.cs:line 134
   at InvokeStub_GivenThatWeWantToRunILLink1.ILLink_links_simple_app_without_analysis_warnings_and_it_runs(Object, Span`1)
   at System.Reflection.RuntimeMethodInfo.Invoke(Object obj, BindingFlags invokeAttr, Binder binder, Object[] parameters, CultureInfo culture)

Known issue validation

Build: 🔎 https://dev.azure.com/dnceng-public/public/_build/results?buildId=1467980
Error message validated: [System\.IO\.IOException : The process cannot access the file '/datadisks/disk1/work/.*-msbuild.binlog' because it is being used by another process\.]
Result validation: ✅ Known issue matched with the provided build.
Validation performed at: 6/17/2026 3:34:51 PM UTC

Report

Build	Repository	Test	Pull Request
1467980	dotnet/sdk	Microsoft.NET.Publish.Tests.GivenThatWeWantToRunILLink1.ILLink_links_simple_app_without_analysis_warnings_and_it_runs	#54729

Summary

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

Known issue validation

Build: 🔎 https://dev.azure.com/dnceng-public/public/_build/results?buildId=1467980
Error message validated: [System\.IO\.IOException : The process cannot access the file '/datadisks/disk1/work/.*-msbuild.binlog' because it is being used by another process\.]
Result validation: ✅ Known issue matched with the provided build.
Validation performed at: 6/17/2026 3:34:51 PM UTC

Known issue validation

Build: 🔎 https://dev.azure.com/dnceng-public/public/_build/results?buildId=1467980
Error message validated: [System\.IO\.IOException : The process cannot access the file '.*msbuild\.binlog' because it is being used by another process\.]
Result validation: ✅ Known issue matched with the provided build.
Validation performed at: 6/17/2026 7:16:45 PM UTC

Report

Build	Repository	Test	Pull Request
1469529	dotnet/sdk	Microsoft.NET.Publish.Tests.GivenThatWeWantToRunILLink1.ILLink_links_simple_app_without_analysis_warnings_and_it_runs	#52302
1469315	dotnet/sdk	Microsoft.NET.Publish.Tests.GivenThatWeWantToRunILLink1b.ILLink_IsTrimmable_metadata_can_override_attribute	#54744
1469283	dotnet/sdk	Microsoft.NET.Publish.Tests.GivenThatWeWantToRunILLink1.ILLink_links_simple_app_without_analysis_warnings_and_it_runs
1469216	dotnet/sdk	Microsoft.NET.Publish.Tests.GivenThatWeWantToRunILLink1b.ILLink_errors_fail_the_build	#54722
1467980	dotnet/sdk	Microsoft.NET.Publish.Tests.GivenThatWeWantToRunILLink1.ILLink_links_simple_app_without_analysis_warnings_and_it_runs	#54729

Summary

24-Hour Hit Count	7-Day Hit Count	1-Month Count
5	5	5

Known issue validation

Build: 🔎 https://dev.azure.com/dnceng-public/public/_build/results?buildId=1467980
Error message validated: [System\.IO\.IOException : The process cannot access the file '/datadisks/disk1/work/.*-msbuild.binlog' because it is being used by another process\.]
Result validation: ✅ Known issue matched with the provided build.
Validation performed at: 6/17/2026 3:34:51 PM UTC

Known issue validation

Build: 🔎 https://dev.azure.com/dnceng-public/public/_build/results?buildId=1467980
Error message validated: [System\.IO\.IOException : The process cannot access the file '.*msbuild\.binlog' because it is being used by another process\.]
Result validation: ✅ Known issue matched with the provided build.
Validation performed at: 6/17/2026 7:16:45 PM UTC

[github-actions]

This Known Build Error has had 0 hits in the past month and has been labeled stale. It will be auto-closed in 7 days if the hit count remains at 0. Add the keep-open label to prevent auto-closure.

[MichaelSimons]

Pattern Updated

Updated the Known Build Error pattern to cover both Linux and Windows paths:

Old pattern (Linux-only):

System\.IO\.IOException : The process cannot access the file '/datadisks/disk1/work/.*-msbuild.binlog' because it is being used by another process\.

New pattern (cross-platform):

System\.IO\.IOException : The process cannot access the file '.*msbuild\.binlog' because it is being used by another process\.

Other changes:

• BuildRetry changed from false to true — this is a transient file lock issue that typically clears on retry
• Title and leg description generalized (not specific to one test)

Triggered by: Build 1468429 (PR #54804) — same IOException but on Windows (C:\h\w\...\msbuild.binlog)

Validation:

• ✅ Pattern matches the Windows error from build 1468429
• ✅ Pattern matches the original Linux error
• ✅ Pattern did not match 3 recent passing builds (good specificity)