Offload: Build offload as a single Step #150108

ZuseZ4 · 2025-12-17T18:28:40Z

Since it looks like we'll postpone enabling offload in CI for a bit, I factored out these improvements which we want independently. I locally tested both build options successfully, the in-tree-clang build, as well as the build where we provide a path to an external clang.

rustbot · 2025-12-17T18:28:44Z

This PR modifies src/bootstrap/src/core/config.

If appropriate, please update CONFIG_CHANGE_HISTORY in src/bootstrap/src/utils/change_tracker.rs.

This PR changes how LLVM is built. Consider updating src/bootstrap/download-ci-llvm-stamp.

This PR modifies bootstrap.example.toml.

If appropriate, please update CONFIG_CHANGE_HISTORY in src/bootstrap/src/utils/change_tracker.rs.

rustbot · 2025-12-17T18:28:46Z

Kobzol is not on the review rotation at the moment.
They may take a while to respond.

rustbot · 2025-12-17T18:32:14Z

This PR was rebased onto a different main commit. Here's a range-diff highlighting what actually changed.

Rebasing is a normal part of keeping PRs up to date, so no action is needed—this note is just to help reviewers.

Kobzol

Left some comments, otherwise it looks reasonable.

View changes since this review

bootstrap.example.toml

src/bootstrap/src/core/config/config.rs

src/bootstrap/src/core/config/toml/llvm.rs

src/bootstrap/src/core/build_steps/llvm.rs

src/bootstrap/src/core/build_steps/compile.rs

Kobzol · 2025-12-19T16:06:25Z

@rustbot author

ZuseZ4 · 2025-12-22T17:32:02Z

@rustbot review

Kobzol · 2025-12-29T10:25:43Z

Thanks, looks good!

@bors r+

bors · 2025-12-29T10:25:46Z

📌 Commit f3b16d8 has been approved by Kobzol

It is now in the queue for this repository.

Offload: Build offload as a single Step r? ``@Kobzol`` Since it looks like we'll postpone enabling offload in CI for a bit, I factored out these improvements which we want independently. I locally tested both build options successfully, the in-tree-clang build, as well as the build where we provide a path to an external clang.

Rollup of 6 pull requests Successful merges: - #150108 (Offload: Build offload as a single Step) - #150262 (slice iter cleanup: replace checked_sub with saturating_sub) - #150427 (add has_offload/needs-offload to the test infra) - #150458 (fix running stdlib doctests in Miri in CI) - #150477 (Fix enum variant suggestion consuming trailing parenthesis) - #150478 (Fix new bors config) r? `@ghost` `@rustbot` modify labels: rollup

Rollup merge of #150108 - ZuseZ4:offload-build-rework, r=Kobzol Offload: Build offload as a single Step r? `@Kobzol` Since it looks like we'll postpone enabling offload in CI for a bit, I factored out these improvements which we want independently. I locally tested both build options successfully, the in-tree-clang build, as well as the build where we provide a path to an external clang.

rustbot added S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. T-bootstrap Relevant to the bootstrap subteam: Rust's build system (x.py and src/bootstrap) labels Dec 17, 2025

rustbot assigned Kobzol Dec 17, 2025

ZuseZ4 force-pushed the offload-build-rework branch from 93bc6ea to 4b2d2b9 Compare December 17, 2025 18:32