9f76214854
This reverts commit a240ccd81c74c105b6f5fe84c46f8d36edb7e306, reversing changes made to 393fdc10483da930cdbb00eabc3635030d2e776f. This PR was likely responsible for a relatively large regression in dist-x86_64-msvc-alt builder times, from approximately 1.7 to 2.8 hours, bringing that builder into the pool of the slowest builders we currently have. This seems to be limited to the alt builder due to needing parallel-compiler enabled, likely leading to slow LLVM compilation for some reason.
For more information about how rustc works, see the rustc dev guide.