Change implementation of -Z gcc-ld and lld-wrapper again

[petrochenkov]

This PR partially reverts #97375 and uses the strategy described in #97402 (comment) instead, thus fixes #97755.

[rust-highfive]

r? @compiler-errors

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[compiler-errors]

r? compiler

[michaelwoerister]

Sorry for not following up sooner.

@petrochenkov, do you have a reviewer in mind for this? The strategy outlined #97402 (comment) sounds reasonable to me, but I'm lacking the knowledge to determine if there could be problems with it.

cc @Mark-Simulacrum, since this is touching dist.

[Mark-Simulacrum]

bootstrap changes here look fine to me.

[petrochenkov]

r? @lqd maybe

[lqd]

Sorry for the wait, I'm now back from vacation and will take look at this tomorrow.

[lqd]

A test to ensure that -Zgcc-ld=lld works on osx now and in the future would have been good to have (especially with an eye towards the rust-lld MCP) so I've been trying to reproduce the initial issue, without success unfortunately.

I'm not sure which version of clang (or macos) was used and when/why it starts switching to response files instead of CLI args. Even with many long link args (the CLI was 23K chars), it still seems to work on an M1 on Monterey (maybe this only happens on x64 darwin but it seems doubtful).

This PR looks good to me as well, but I'd like to make sure: @tschuett, does the thumbs up you left on the OP mean that you were able to test this PR on the project triggering #97755 successfully ? Would you have a repository where we could reproduce the issue by any chance ?

I'd like to have an answer and hopefully I can reduce a test out of that, before merging this PR.

But if it's not possible, and @tschuett has indeed validated the fix, r=me (+mark).

[tschuett]

I have 195 crates to build for my application.

> clang --version
Apple clang version 13.1.6 (clang-1316.0.21.2.5)
Target: x86_64-apple-darwin21.6.0
Thread model: posix
InstalledDir: /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin
> rustc +nightly --verbose --version
rustc 1.65.0-nightly (ce36e8825 2022-08-28)
binary: rustc
commit-hash: ce36e88256f09078519f8bc6b21e4dc88f88f523
commit-date: 2022-08-28
host: x86_64-apple-darwin
release: 1.65.0-nightly
LLVM version: 15.0.0

and it failed again. I cannot test this PR. sorry.

[lqd]

Thank you; I have the same clang version.

We could temporarily switch the try builder to osx if we wanted to make a single build for you to try out, but things aren't going to get much worse than "-Zgcc-ld=lld is not working sometimes", and I've stress tested this branch on linux as well without issues.

So I'll test the nightly where this PR lands for the successful osx cases I saw, and hopefully you can keep us updated on how it behaves for you -- we'll keep an eye on possible new issues as well.

@bors r=lqd,Mark-Simulacrum

Thanks @petrochenkov.

[bors]

📌 Commit 6b68921 has been approved by lqd,Mark-Simulacrum

It is now in the queue for this repository.