Backport issue #115951 into .NET 9 and .NET 8 so it work with VS 2026

[DamianSuess]

Description

When publishing C# applications with AOT and only VS 2026 is installed, the findvcvarsall.bat file throws an error. Please implement #115951 into .NET 8 and .NET 9, as the Microsoft.DotNet.ILCompiler toolset throws errors when publishing applications

Reproduction Steps

Steps to Reproduc

1. Only install VS 2026
2. Install .NET 9
3. Include the "Desktop Development with C++" workload via installer
4. Include the ".NET Desktop Development" workload via installer
5. Publish an application with AOT
   • dotnet publish TestApp.csproj /p:PublishProfile=TestApp/PublishProfiles/win-x64.pubxml

Sample win-x64.pubxml

<?xml version="1.0" encoding="utf-8"?>
<!-- https://go.microsoft.com/fwlink/?LinkID=208121. -->
<Project>
  <PropertyGroup>
    <Configuration>Release</Configuration>
    <Platform>Any CPU</Platform>
    <PublishDir>../publish/cli/win-x64</PublishDir>
    <PublishProtocol>FileSystem</PublishProtocol>
    <_TargetId>Folder</_TargetId>
    <TargetFramework>net9.0</TargetFramework>
    <RuntimeIdentifier>win-x64</RuntimeIdentifier>
    <SelfContained>true</SelfContained>
    <PublishReadyToRun>false</PublishReadyToRun>
    <PublishSingleFile>false</PublishSingleFile>
  </PropertyGroup>
</Project>

Expected behavior

Not to fail.

Use the methodology in, #115951

Actual behavior

Throws error stating, "Make sure to install the Desktop Development for C++ workload. For ARM64 development also install C++ ARM64 build tools." Even through they are already installed.

Regression?

No response

Known Workarounds

Manually edit Line 18 in, findvcvarsall.bat, removing the line -version [16^,18^) ^

FOR /F "tokens=*" %%i IN (
    '"%vswherePath%" -latest -prerelease -products * ^
    -requires Microsoft.VisualStudio.Component.VC.Tools.%toolsSuffix% ^
    -version [16^,18^) ^
    -property installationPath'
) DO SET vsBase=%%i

Configuration

No response

Other information

No response

[dotnet-policy-service]

Tagging subscribers to this area: @agocke, @MichalStrehovsky, @jkotas
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[MichalStrehovsky]

It's on track: #120914, #120913, waiting for the merge window.

[DamianSuess]

Thank you @MichalStrehovsky, you just made Christmas come early this year.