Enable x86 AOT compilation for components build

[am11]

Now that global.json is pointing to p6 (which has an SDK fix for win-x86), lets try enabling it.

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[am11]

...
  Generating native code
  ILCompiler -> D:\a\_work\1\s\artifacts\bin\coreclr\windows.x86.Checked\ilc-published\
...

[jkotas]

This change looks good.

I think there is a separate question whether we should be building win-x86 ilc and crossgen2 binaries at all. I have tried to compile hello world using win-x86 ilc from .NET 9 P6 SDK and the build insists on cross-compiling using win-x64 ilc ("Add a PackageReference for 'runtime.win-x64.Microsoft.DotNet.ILCompiler' to allow cross-compilation for x86"). cc @filipnavara

[filipnavara]

I have tried to compile hello world using win-x86 ilc from .NET 9 P6 SDK and the build insists on cross-compiling using win-x64 ilc ("Add a PackageReference for 'runtime.win-x64.Microsoft.DotNet.ILCompiler' to allow cross-compilation for x86").

That’s somewhat unexpected. It was possible to use for building the tests last time I tried. It was not necessarily a good experience since it was prone to run out of virtual memory on any bigger inputs.

[jkotas]

We use custom setup for tests, so I can believe that it is possible to use it for tests. I was looking at it from the user point of view. As far as I can tell, there is no way for regular user project files to use the win-x86 ilc binary.

[am11]

@jkotas, second commit fixes the publishing issue you described; when dotnet.exe or ilc.exe is x86, running (emulating) on x64 or arm64 machine. x86 dotnet.exe or ilc.exe on x86 windows were working fine with p6, so it wasn't widespread.

[MichalStrehovsky]

Thanks!

[MichalStrehovsky]

@agocke, are you okay with merging this? I noticed your #105826 and this takes a dependency on preview 6. I don't have context on the other PR.

[agocke]

There were a couple issues popping up that seemed to be caused by low frequency bugs in the preview 6 SDK. I was evaluating if we could roll it back, while monitoring the build. Overall, I don’t think we should roll back. The issues most commonly blocking the build don’t seem to be ones that would be fixed by a rollback, and we’re close to p7. I think it’s fine to merge this.

[MichalStrehovsky]

There were a couple issues popping up that seemed to be caused by low frequency bugs in the preview 6 SDK. I was evaluating if we could roll it back, while monitoring the build. Overall, I don’t think we should roll back. The issues most commonly blocking the build don’t seem to be ones that would be fixed by a rollback, and we’re close to p7. I think it’s fine to merge this.

Thank you! Merging!