Streamlining support for standalone builds

[banach-space]

Hey @mgorny !

@mgorny

I’d like to try working on streamlining the support for standalone builds of different LLVM projects (e.g. clang, lld…).

Thanks for volunteering! Big +1 from me.

I think that this was discussed not so long ago: https://discourse.llvm.org/t/rfc-stand-alone-build-support/. I am assuming that this is meant to build on top of what @tstellar worked on?

@mgorny

I’d like to first hear from other users of standalone builds about their use cases.

I believe that some Flang developers use it in their workflows, see Building flang standalone. IIRC, @psteinfeld wrote that particular section of the documentation There’s also flang-aarch64-out-of-tree that is maintained to test Flang standalone builds.

While I don’t use standalone builds personally, I very supportive of everything that makes our CMake scripts more uniform and cleaner and I really appreciate you proposing this.

-Andrzej