WindowsDesktop and ASP.NET are not considered linkable frameworks

[agocke]

When trimming any WinForms, WPF, or ASP.NET, the whole framework is not linked because it is considered user code.

This may not be relevant if we do not support trimming these frameworks, but otherwise we should mark them as linkable as soon as we have fixed preliminary warnings.

[dotnet-issue-labeler]

I couldn't figure out the best area label to add to this issue. If you have write-permissions please help me learn by adding exactly one area label.

[ghost]

Tagging subscribers to 'linkable-framework': @eerhardt, @vitek-karas, @LakshanF, @tannergooding, @sbomer
See info in area-owners.md if you want to be subscribed.

Issue Details

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When trimming any WinForms, WPF, or ASP.NET, the whole framework is not linked because it is considered user code.

This may not be relevant if we do not support trimming these frameworks, but otherwise we should mark them as linkable as soon as we have fixed preliminary warnings.

Author:	agocke
Assignees:	-
Labels:	area-Meta, linkable-framework, untriaged
Milestone:	6.0.0

[eerhardt]

We have a feature now that any library can add [assembly:AssemblyMetadata("IsTrimmable", "True")], and when TrimMode=link that assembly will be trimmed.

See #48428
https://github.com/mono/linker/blob/main/docs/design/trimmed-assemblies.md#assemblymetadataistrimmable-true.

I think this issue can be closed now in dotnet/runtime. It is possible for those libraries to "self-serve" here. No work is needed in dotnet/runtime.

[marek-safar]

Yep, there is not much left to do in runtime. It'd be better to open an issue in WinForms, WPF repos with links on how to make their SDK trimmable (that's what we did for other repos).

[eerhardt]

Closing as per above discussion.

[agocke]

Thanks, the guidance above looks good.