Do not enable LLD by default in the dist profile by Kobzol · Pull Request #143255 · rust-lang/rust

Kobzol · 2025-06-30T20:04:43Z

History of us building & shipping LLD for dist builds:

We used to unconditionally build & ship LLD in bootstrap
This was causing problems for people doing custom dist builds (https://rust-lang.zulipchat.com/#narrow/stream/326414-t-infra.2Fbootstrap/topic/MSVC.20Runtime.20mismatch.20when.20building.20LLD)
ignore llvm::Lld if lld is not enabled #126701 made shipping of LLD optional, but to preserve previous behavior, it forcefully enabled rust.lld = true in the dist profile by default, and overwrote the default to false on our CI for external LLVM builds.
- This also didn't match the documentation of rust.lld in bootstrap.example.toml, which I previously missed.
However, since the external LLVM opt-out was only implemented for our CI, and not for all dist users, this started causing issues for people disting with external LLVM (rustc-1.88.0 does not build using external LLVM due to missing rust-lld #143076). The problem is that the default shouldn't be "true", but "LLD is enabled when LLVM isn't external", but this is not possible to do only in TOML.

So this PR reverses the behavior. LLD is not enabled by default in dist anymore. We switch our CI to opt into disting LLD, unless an external LLVM is used. External dist users can still opt into enabling LLD, but if they do so while also using external LLVM, they will now get a hard error.

r? @jieyouxu

try-job: x86_64-mingw*
try-job: dist-x86_64-linux

rustbot · 2025-06-30T20:04:49Z

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

Kobzol · 2025-06-30T20:05:09Z

@bors2 try

rust-bors · 2025-06-30T20:05:13Z

⌛ Trying commit 595b89b with merge a41cd18…

To cancel the try build, run the command @bors2 try cancel.

Do not enable LLD by default in the dist profile History of us building & shipping LLD for `dist` builds: 1) We used to unconditionally build & ship LLD in bootstrap 2) This was causing problems for people doing custom `dist` builds (https://rust-lang.zulipchat.com/#narrow/stream/326414-t-infra.2Fbootstrap/topic/MSVC.20Runtime.20mismatch.20when.20building.20LLD) 3) #126701 made shipping of LLD optional, but to preserve previous behavior, it forcefully enabled `rust.lld = true` in the `dist` profile by default, and overwrote the default to `false` on our CI for external LLVM builds. - This also didn't match the documentation of `rust.lld` in `bootstrap.example.toml`, which I previously missed. 4) However, since the external LLVM opt-out was only implemented for our CI, and not for all `dist` users, this started causing issues for people `dist`ing with external LLVM (#143076). The problem is that the default shouldn't be "true", but "LLD is enabled when LLVM isn't external", but this is not possible to do only in TOML. So this PR reverses the behavior. LLD is not enabled by default in `dist` anymore. We switch our CI to *opt into* disting LLD, unless an external LLVM is used. External `dist` users can still opt into enabling LLD, but if they do so while also using external LLVM, they will now get a [hard error](#143175). r? `@jieyouxu` try-job: x86_64-mingw try-job: dist-x86_64-linux

rust-bors · 2025-06-30T20:06:38Z

💔 Test failed

CI ❌

Kobzol · 2025-06-30T20:07:35Z

@bors2 try

rust-bors · 2025-06-30T20:07:39Z

⌛ Trying commit 595b89b with merge 0006654…

To cancel the try build, run the command @bors2 try cancel.

Do not enable LLD by default in the dist profile History of us building & shipping LLD for `dist` builds: 1) We used to unconditionally build & ship LLD in bootstrap 2) This was causing problems for people doing custom `dist` builds (https://rust-lang.zulipchat.com/#narrow/stream/326414-t-infra.2Fbootstrap/topic/MSVC.20Runtime.20mismatch.20when.20building.20LLD) 3) #126701 made shipping of LLD optional, but to preserve previous behavior, it forcefully enabled `rust.lld = true` in the `dist` profile by default, and overwrote the default to `false` on our CI for external LLVM builds. - This also didn't match the documentation of `rust.lld` in `bootstrap.example.toml`, which I previously missed. 4) However, since the external LLVM opt-out was only implemented for our CI, and not for all `dist` users, this started causing issues for people `dist`ing with external LLVM (#143076). The problem is that the default shouldn't be "true", but "LLD is enabled when LLVM isn't external", but this is not possible to do only in TOML. So this PR reverses the behavior. LLD is not enabled by default in `dist` anymore. We switch our CI to *opt into* disting LLD, unless an external LLVM is used. External `dist` users can still opt into enabling LLD, but if they do so while also using external LLVM, they will now get a [hard error](#143175). r? `@jieyouxu` try-job: `x86_64-mingw*` try-job: dist-x86_64-linux

rust-bors · 2025-06-30T23:12:18Z

☀️ Try build successful (CI)
Build commit: 0006654 (000665474f1545b250d77cc0e26fedb2ebd07279, parent: c65dccabacdfd6c8a7f7439eba13422fdd89b91e)

bors · 2025-07-01T03:29:55Z

☔ The latest upstream changes (presumably #143254) made this pull request unmergeable. Please resolve the merge conflicts.

rustbot · 2025-07-01T06:20:23Z

This PR modifies src/bootstrap/defaults.

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

jieyouxu

Thanks

jieyouxu · 2025-07-01T06:27:20Z

@bors r+ rollup

bors · 2025-07-01T06:27:22Z

📌 Commit c2daa28 has been approved by jieyouxu

It is now in the queue for this repository.

Rollup of 12 pull requests Successful merges: - #136801 (Implement `Random` for tuple) - #141867 (Describe Future invariants more precisely) - #142760 (docs(fs): Touch up grammar on lock api) - #143181 (Improve testing and error messages for malformed attributes) - #143210 (`tests/ui`: A New Order [19/N] ) - #143212 (`tests/ui`: A New Order [20/N]) - #143230 ([COMPILETEST-UNTANGLE 2/N] Make some compiletest errors/warnings/help more visually obvious) - #143240 (Port `#[rustc_object_lifetime_default]` to the new attribute parsing …) - #143255 (Do not enable LLD by default in the dist profile) - #143262 (mir: Mark `Statement` and `BasicBlockData` as `#[non_exhaustive]`) - #143269 (bootstrap: make comment more clear) - #143279 (Remove `ItemKind::descr` method) Failed merges: - #143237 (Port `#[no_implicit_prelude]` to the new attribute parsing infrastructure) r? `@ghost` `@rustbot` modify labels: rollup

Rollup merge of #143255 - Kobzol:disable-lld-by-default, r=jieyouxu Do not enable LLD by default in the dist profile History of us building & shipping LLD for `dist` builds: 1) We used to unconditionally build & ship LLD in bootstrap 2) This was causing problems for people doing custom `dist` builds (https://rust-lang.zulipchat.com/#narrow/stream/326414-t-infra.2Fbootstrap/topic/MSVC.20Runtime.20mismatch.20when.20building.20LLD) 3) #126701 made shipping of LLD optional, but to preserve previous behavior, it forcefully enabled `rust.lld = true` in the `dist` profile by default, and overwrote the default to `false` on our CI for external LLVM builds. - This also didn't match the documentation of `rust.lld` in `bootstrap.example.toml`, which I previously missed. 4) However, since the external LLVM opt-out was only implemented for our CI, and not for all `dist` users, this started causing issues for people `dist`ing with external LLVM (#143076). The problem is that the default shouldn't be "true", but "LLD is enabled when LLVM isn't external", but this is not possible to do only in TOML. So this PR reverses the behavior. LLD is not enabled by default in `dist` anymore. We switch our CI to *opt into* disting LLD, unless an external LLVM is used. External `dist` users can still opt into enabling LLD, but if they do so while also using external LLVM, they will now get a [hard error](#143175). r? `@jieyouxu` try-job: `x86_64-mingw*` try-job: dist-x86_64-linux

Upstream have changed to no longer unconditionally build LLD in bootstrap, instead only building it if a system LLVM was not in use. The defaults were not updated before 1.88 was released to reflect this, however, so the boostrap will still expect `rust-lld` to have been built. This change is recommended by upstream in rust-lang/rust#143076 (comment) See also rust-lang/rust#143255 which will fix this for post-1.88 releases (which shouldn't matter for us, as we'll still have this configuration change in place).

ognevny · 2025-07-25T20:19:02Z

src/bootstrap/src/utils/change_tracker.rs

+    ChangeInfo {
+        change_id: 143255,
+        severity: ChangeSeverity::Warning,
+        summary: "`llvm.lld` is no longer enabled by default for the dist profile.",


shouldn't it be rust.lld instead? or I missed something?

rustbot assigned jieyouxu Jun 30, 2025

rustbot added A-testsuite Area: The testsuite used to check the correctness of rustc T-bootstrap Relevant to the bootstrap subteam: Rust's build system (x.py and src/bootstrap) T-infra Relevant to the infrastructure team, which will review and decide on the PR/issue. labels Jun 30, 2025

Kobzol mentioned this pull request Jun 30, 2025

rustc-1.88.0 does not build using external LLVM due to missing rust-lld #143076

Open

bors added the S-waiting-on-author Status: This is awaiting some action (such as code changes or more information) from the author. label Jul 1, 2025

Do not enable LLD by default in the dist profile

c2daa28

Kobzol force-pushed the disable-lld-by-default branch from 595b89b to c2daa28 Compare July 1, 2025 06:20

Kobzol marked this pull request as ready for review July 1, 2025 06:20

rustbot added the S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. label Jul 1, 2025

Kobzol mentioned this pull request Jul 1, 2025

Hide outdated comments rust-lang/bors#334

Closed

jieyouxu removed the S-waiting-on-author Status: This is awaiting some action (such as code changes or more information) from the author. label Jul 1, 2025

jieyouxu approved these changes Jul 1, 2025

View reviewed changes

bors added S-waiting-on-bors Status: Waiting on bors to run and complete tests. Bors will change the label on completion. and removed S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. labels Jul 1, 2025

GuillaumeGomez mentioned this pull request Jul 1, 2025

Rollup of 12 pull requests #143287

Merged

bors merged commit 8b0e7d7 into rust-lang:master Jul 1, 2025
10 checks passed

rustbot added this to the 1.90.0 milestone Jul 1, 2025

Kobzol deleted the disable-lld-by-default branch July 2, 2025 05:22

ognevny reviewed Jul 25, 2025

View reviewed changes

Uh oh!

Conversation

Kobzol commented Jun 30, 2025 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Uh oh!

rustbot commented Jun 30, 2025

Uh oh!

Kobzol commented Jun 30, 2025

Uh oh!

rust-bors bot commented Jun 30, 2025

Uh oh!

rust-bors bot commented Jun 30, 2025

Uh oh!

Kobzol commented Jun 30, 2025

Uh oh!

rust-bors bot commented Jun 30, 2025

Uh oh!

rust-bors bot commented Jun 30, 2025

Uh oh!

bors commented Jul 1, 2025

Uh oh!

rustbot commented Jul 1, 2025

Uh oh!

jieyouxu left a comment

Choose a reason for hiding this comment

Uh oh!

jieyouxu commented Jul 1, 2025

Uh oh!

bors commented Jul 1, 2025

Uh oh!

Uh oh!

ognevny Jul 25, 2025

Choose a reason for hiding this comment

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

5 participants

Kobzol commented Jun 30, 2025 •

edited

Loading