[NETSDKE2E][Green]Failed to debug 8.0 projects with error ".csproj does not support debugging", when SDK 8.0 installed alone.

[yinjiehe01]

REGRESSION INFO
Not repro on April release.
Repro on May pre-release 3,4,5 and 6.

INSTALL STEP

1. Install SDK 8.0.422.
2. Install latest VS Code and C# dev kit May prerelease 6 (C# May pre-release 6) extension.

REPRO STEPS

1. Open vs code -> Create .NET project ->select a project e.g. console app.
2. F1->Debug: Select and Start Debugging ->C# -> C#:project name

Expected
The project debug successfully.

Actual
The project debug failed with error ".csproj does not support debugging.No launchable target found."

[yinjiehe01]

Related to bug #3001

[LittleLittleCloud]

@yinjiehe01 can you provide the C#DK tracing log, wondering if it is related to missing .NET SDK for tooling

[LittleLittleCloud]

I can reproduce it on wsl && windows with just .NET SDK 8.0.422 + latest pre-released C#DK

[yinjiehe01]

@LittleLittleCloud Sure, here is the C#DK log

C#DevKit.log

[LittleLittleCloud]

After talking to Lifeng,, it seems that .NET 8.0.3xx/4xx returns an empty list because the C# Dev Kit on-demand cache optimization is incompatible with the MSBuild version shipped in those SDKs, causing CPS state propagation to fail. .NET 9 SDKs contain newer MSBuild bits where that incompatibility is fixed, so the list is populated correctly.

workaround

• disable the on-demand cache ("Optimize Memory Usage") feature by disable useNewMemoryOptimization in .vscode/settings.json

{
    "dotnet.projectsystem.useNewMemoryOptimization": false
}

• downgrade SDK to 8.2.* or upgrade to .net 9 or newer