Opt-out of default target framework filtering in source-build infra

[NikolaMilosavljevic]

runtime doesn't use target framework filtering in source-build infra.

We plan to switch the filtering logic to be on by default, and require repos to explicitly opt-out, see dotnet/source-build#3362

'runtime' is already filtering target frameworks using a custom model, and this work will not have an impact: #83899

[ghost]

Tagging subscribers to this area: @dotnet/area-infrastructure-libraries
See info in area-owners.md if you want to be subscribed.

Issue Details

---

runtime doesn't use target framework filtering in source-build infra.

We plan to switch the filtering logic to be on by default, and require repos to explicitly opt-out, see dotnet/source-build#3362

'runtime' is already filtering target frameworks using a custom model, and this work will not have an impact: #83899

Author:	NikolaMilosavljevic
Assignees:	NikolaMilosavljevic
Labels:	area-Infrastructure-libraries
Milestone:	-

[ViktorHofer]

Please move this here:

runtime/Directory.Build.props

Line 293 in 2d9cb2d

<PropertyGroup>

Otherwise target framework filtering could happen outside of the "-sb" build when passing /p:DotNetBuildFromSource=true in.

[mmitche]

I thought that ArcadeBuildFromSource was basically the default at this point and that source build was not generally functional without it. That switch would bring in this file. @dotnet/source-build-internal?

[ViktorHofer]

Linux partners actively use the /p:DotNetBuildFromSource switch in their CI, cc @tmds

[mmitche]

Those are usually used as a combo though, I think? Otherwise SourceBuild.props wouldn't be the place to put any source build specific properties.

[ViktorHofer]

Nope, they use the source build switch without depending on Arcade powered source build. See #81480 for more details