[lld] [llvm] [DTLTO][LLD][ELF] Add support for Integrated Distributed ThinLTO (PR #142757)

[via llvm-commits]

bd1976bris wrote:

> If it helps, I can remove support for thin archive bitcode members in this patch? We’re likely to revisit and revise this area anyway when we add support for non-thin archives and DTLTO. Let me know what you prefer. Thanks!

@maskray and @teresajohnson - I've pushed a change to remove the DTLTO support for thin-archive bitcode members from this patch, and I've updated the PR description accordingly.

This simplifies the patch and makes it more amenable to review. We're also actively exploring how to support bitcode members in non-thin archives, and that work may lead to a different approach for thin-archive support than what was originally proposed here.

If that ends up being the case, reviewing the current implementation would be a potential waste of your time.

Note: without thin-archive support, this patch is no longer sufficient to self-host an LLVM build using DTLTO. While --start-lib/--end-lib could theoretically be used instead, it's not clear (to me) how to integrate that with the current LLVM build system as easily as thin archives.

I hope this change is helpful. Please let me know if you disagree, and I’ll be happy to reinstate.

https://github.com/llvm/llvm-project/pull/142757