rust-lang / rust-lang/rust

bootstrap build order - missing lld for autodiff/offload

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#160,584 3 comments 0 reactions 1 assignee View on GitHub

@ZuseZ4 is already working on this.

Since Aug 5, 2026.

C-bug F-autodiff F-gpu_offload T-bootstrap
Dominant language
Rust
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Description

Summary

Mostly an issue for new setups (e.g. clean server nodes)
I usually want to build autodiff, offload, clang, lld, llvm and rustc.
Autodiff has the problem that it has few, but huge, object files, so gnu-ld takes multiple minutes to link, and later offload steps straight-up fail without another lld on path. I should move the enzyme/lld builds to be one of the last steps, so that lld is available by then.

Command used
./x build --stage 1 library
Expected behaviour

We first run the lld step, then other ones.

Actual behaviour
Bootstrap configuration (bootstrap.toml)
https://rustc-dev-guide.rust-lang.org/offload/installation.html#build-instructions
Operating system

linux

HEAD

latest main

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