"dotnet build-server shutdown" warning for missing dll

[pjanotti]

It seems that a recent upgrade of the runtime on GH runners started to trigger a warning and non-zero exit code for the dotnet build-server shutdown command executed from tests in our repo. This seems to happen with runtime 8.0.7, but, it is also not 100% consistent. sometimes it passes in a retry - the test checks for the exit code of the command. It looks like a bug that should be fixed. Could you please confirm if that is the case?

  13:16:22 [DBG]  Running: dotnet build-server shutdown
  13:16:22 [DBG]  ProcessId: 6839
  13:16:22 [DBG]  Exit Code: 1
  13:16:22 [DBG]  StandardOutput:
  13:16:22 [DBG]  Shutting down MSBuild server...
  13:16:22 [DBG]  Shutting down VB/C# compiler server...
  13:16:22 [DBG]  VB/C# compiler server failed to shut down: The shutdown command failed: Error:
  13:16:22 [DBG]    An assembly specified in the application dependencies manifest (VBCSCompiler.deps.json) was not found:
  13:16:22 [DBG]      package: 'Microsoft.CodeAnalysis.ExternalAccess.RazorCompiler', version: '4.10.0-3.24314.14'
  13:16:22 [DBG]      path: 'Microsoft.CodeAnalysis.ExternalAccess.RazorCompiler.dll'
  13:16:22 [DBG]  
  13:16:22 [DBG]  MSBuild server shut down successfully.
  13:16:22 [DBG]  

@Kielek investigated, see here, and

found the Microsoft.CodeAnalysis.ExternalAccess.RazorCompiler.dll file in following locations

C:\Program Files\dotnet\sdk\8.0.302\DotnetTools\dotnet-format
C:\Program Files\dotnet\sdk\8.0.303\DotnetTools\dotnet-watch\8.0.303-servicing.24317.6\tools\net8.0\any
C:\Program Files\dotnet\sdk\8.0.400-preview.0.24324.5\DotnetTools\dotnet-watch\8.0.400-preview.24323.4\tools\net8.0\any\

and what is more important there is no such file in:

C:\Program Files\dotnet\sdk\8.0.303\Roslyn\bincore\Microsoft.CodeAnalysis.ExternalAccess.RazorCompiler.dll
C:\Program Files\dotnet\sdk\8.0.400-preview.0.24324.5\Roslyn\bincore\Microsoft.CodeAnalysis.ExternalAccess.RazorCompiler.dll

When I manually copied the appropriate version locally to these folders, dotnet build-server shutdown executed from unit tests started working. I suppose that this file should be deployed there or reference should be removed.

cc @rajkumar-rangaraj

[333fred]

Converted to #74430.