Unify tryrun scripts

[MichalStrehovsky]

#86781 (comment)

We have tryrun.cmake that is mostly used for -cross builds.

Then we have similar things in runtime/src/native/libs/configure.cmake and https://github.com/dotnet/runtime/blob/main/eng/native/tryrun_ios_tvos.cmake.

We should reconcile this.

Related: #56622

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Issue Details

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#86781 (comment)

We have tryrun.cmake that is mostly used for -cross builds.

Then we have similar things in runtime/src/native/libs/configure.cmake and https://github.com/dotnet/runtime/blob/main/eng/native/tryrun_ios_tvos.cmake.

We should reconcile this.

Related: #56622

Author:	MichalStrehovsky
Assignees:	-
Labels:	area-Infrastructure-libraries, os-android
Milestone:	-

[janvorli]

@MichalStrehovsky the tryrun.cmake contains values for cross build that the configure.cmake would detect if the build was executed on the target OS. It is used only for checks that execute code, so they cannot be evaluated on the build hosting OS. This is a cmake concept - the tryrun.cmake is meant to be separate, as it is loaded by cmake as an initialization of its cache.
It is not clear to me how we could reasonably unify these.

[MichalStrehovsky]

@MichalStrehovsky the tryrun.cmake contains values for cross build that the configure.cmake would detect if the build was executed on the target OS. It is used only for checks that execute code, so they cannot be evaluated on the build hosting OS.

Yes, it's the same thing that the quoted part of configure.cmake is also doing. It's not clear why we spread these around the codebase

[janvorli]

Oh, I am surprised to see it in the configure.cmake in libraries. The ones in coreclr don't have that, they use the tryrun.cmake.

[ViktorHofer]

@akoeplinger as you are assigned, should this stay in 8.0.0 or be moved?

[akoeplinger]

@ViktorHofer it can stay in 8.0 for now