Summary
The two native Windows ARM64 test cells are commented out in eng/src/TeamCity/TeamCityConfigurations.cs and should be restored once Visual Studio 2027 reaches the stable channel.
TestWinArm64Vs1811Net100BuildAndUnitTestWinArm64Vs1811Net100PatternsUnitsTimeSensitive
Why they were disabled
Both run on a bare agent with no container, so the tool chain is installed on the machine rather than baked into an image. The agent does not have the Visual Studio the platform baseline names, and fails before building anything:
VS 18.11-insiders not found. Installed: 17.14.23, 18.1.1.
The agent is below the floor rather than merely behind it. 18.1.1 is a Dev18 build, but PB-2027.0 puts the Visual Studio floor at 18.9, so pointing the cells at what is installed would put them on an unsupported toolchain, which rule 10 does not allow.
Installing 18.11 while it is a preview would mean reinstalling it by hand for every release candidate, on a machine whose only job is to test one architecture. That is not worth paying for a toolchain that is about to settle.
What to do
When Visual Studio 2027 reaches stable, expected November 2026:
- Install it on the Windows ARM64 agent.
- Uncomment the two
CreateWindowsArm64TestCell calls in eng/src/TeamCity/TeamCityConfigurations.cs.
- Regenerate with
Build.ps1 generate-scripts — .teamcity/** is generated and a hand edit is lost on the next run.
- Run
RunAllNet100Tests and confirm both cells pass.
This is the same event that moves the Visual Studio selector off the Preview channel, tracked in Documentation/PB-2027.0-TODO.md item 1. The two are worth doing together.
Why this matters
Rule 10 of the platform baseline says a supported platform is a tested one. PB-2027.0 justifies the ARM64 .NET Framework floor of 4.8.1 by the native ARM64 host, and these cells are what exercises it. The Linux ARM64 cells cover the architecture but not the Windows native host, so while these are disabled that column is claimed and not tested.
Recorded in Documentation/PB-2027.0-TODO.md item 13.
-- Claude for gfraiteur
Summary
The two native Windows ARM64 test cells are commented out in
eng/src/TeamCity/TeamCityConfigurations.csand should be restored once Visual Studio 2027 reaches the stable channel.TestWinArm64Vs1811Net100BuildAndUnitTestWinArm64Vs1811Net100PatternsUnitsTimeSensitiveWhy they were disabled
Both run on a bare agent with no container, so the tool chain is installed on the machine rather than baked into an image. The agent does not have the Visual Studio the platform baseline names, and fails before building anything:
The agent is below the floor rather than merely behind it. 18.1.1 is a Dev18 build, but PB-2027.0 puts the Visual Studio floor at 18.9, so pointing the cells at what is installed would put them on an unsupported toolchain, which rule 10 does not allow.
Installing 18.11 while it is a preview would mean reinstalling it by hand for every release candidate, on a machine whose only job is to test one architecture. That is not worth paying for a toolchain that is about to settle.
What to do
When Visual Studio 2027 reaches stable, expected November 2026:
CreateWindowsArm64TestCellcalls ineng/src/TeamCity/TeamCityConfigurations.cs.Build.ps1 generate-scripts—.teamcity/**is generated and a hand edit is lost on the next run.RunAllNet100Testsand confirm both cells pass.This is the same event that moves the Visual Studio selector off the Preview channel, tracked in
Documentation/PB-2027.0-TODO.mditem 1. The two are worth doing together.Why this matters
Rule 10 of the platform baseline says a supported platform is a tested one. PB-2027.0 justifies the ARM64 .NET Framework floor of 4.8.1 by the native ARM64 host, and these cells are what exercises it. The Linux ARM64 cells cover the architecture but not the Windows native host, so while these are disabled that column is claimed and not tested.
Recorded in
Documentation/PB-2027.0-TODO.mditem 13.-- Claude for gfraiteur