[lld] [lld][MachO]Multi-threaded i/o. Twice as fast linking a large project. (PR #147134)

[John Holdsworth via llvm-commits]

johnno1962 wrote:

👋, back from my break and I didn't think of anything new to add to the PR other than perhaps expanding the main comment or including a link to this PR as documentation of the approach. As peace seems to have broken out how about we merge this before it snags a conflict? Thanks for all your help and ideas.

https://github.com/llvm/llvm-project/pull/147134