bootstrap: Include feature-gated items in bootstrap tool docs by Zalathar · Pull Request #161900 · rust-lang/rust

Zalathar · 2026-08-28T03:58:57Z

I noticed that the nightly-rustc docs for build_helper don't include the metrics module, because it's gated behind the non-default feature flag feature = "metrics".

This PR fixes that by using --all-features to document all features, and enabling rustdoc's #![feature(doc_cfg)] (via -Zcrate-attr) so that rustdoc will indicate which items require feature flags.

The first two commits are a general cleanup of tool_doc! to pull almost all of its non-trivial code out of the macro and into regular functions.

rustbot · 2026-08-28T03:59:01Z

r? @Mark-Simulacrum

rustbot has assigned @Mark-Simulacrum.
They will have a look at your PR within the next two weeks and either review your PR or reassign to another reviewer.

Use r? to explicitly pick a reviewer

Why was this reviewer chosen?

The reviewer was selected based on:

Owners of files modified in this PR: bootstrap
bootstrap expanded to 6 candidates
Random selection from Mark-Simulacrum, clubby789

Zalathar · 2026-08-28T04:00:01Z

As a follow-up we could also enable this for compiler crates, since a few of them have feature flags to enable nightly-only features when they aren't being used by rust-analyzer.

Zalathar · 2026-08-28T04:05:05Z

I would also like to note that this would have been much more annoying without -Zcrate-attr.

Zalathar · 2026-08-28T04:31:04Z

I really want to blanket allow clippy::too_many_arguments and clippy::type_complexity across all of bootstrap, but I won't do that in this PR.

Kobzol · 2026-08-28T07:37:42Z

r? kobzol

Note that this will conflict a lot with #161716. In general I'm happy to see most of the code move out of a macro.

Kobzol · 2026-08-28T07:38:05Z

Aside: do you find the build_helper/bootstrap docs being present in the nightly rustc docs useful?

Zalathar · 2026-08-28T07:45:01Z

Aside: do you find the build_helper/bootstrap docs being present in the nightly rustc docs useful?

I use the nightly-rustc docs intermittently, but when I do reach for them it's nice to have everything there in one place, especially when I'm not at a computer and can't easily search the source.

Zalathar · 2026-08-28T07:47:58Z

Note that this will conflict a lot with #161716. In general I'm happy to see most of the code move out of a macro.

If conflicts are a concern, I can potentially cut this PR down to just the main fix (within the macro), and defer the macro-extraction to follow-up work.

(I had to do the extraction to work on the fix, but now that I have the fix it should be easy to backport to main.)

Kobzol · 2026-08-28T11:46:44Z

I'd perhaps either do that, or wait for the other PR to get merged, yeah.

Zalathar · 2026-09-02T06:53:32Z

@rustbot blocked (on #161716 to avoid conflicts)

rustbot · 2026-09-04T07:37:40Z

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.

Zalathar · 2026-09-04T07:39:26Z

@rustbot ready

Kobzol · 2026-09-04T08:22:42Z

Looks good, thanks! Feel free to r=me once PR CI is green.

Zalathar · 2026-09-04T09:13:12Z

PR CI is green.

@bors r=Kobzol

rust-bors · 2026-09-04T09:13:15Z

📌 Commit 8f1843d has been approved by Kobzol

It is now in the queue for this repository.

bootstrap: Include feature-gated items in bootstrap tool docs I noticed that the [nightly-rustc docs for `build_helper`](https://doc.rust-lang.org/nightly/nightly-rustc/build_helper/index.html) don't include the `metrics` module, because it's gated behind the non-default feature flag `feature = "metrics"`. This PR fixes that by using `--all-features` to document all features, and enabling rustdoc's `#![feature(doc_cfg)]` [(via -`Zcrate-attr`)](rust-lang#138287) so that rustdoc will indicate which items require feature flags. The first two commits are a general cleanup of `tool_doc!` to pull almost all of its non-trivial code out of the macro and into regular functions.

Rollup of 25 pull requests Successful merges: - #159074 ([PAC] FnAbi, llvm.ptrauth.resign and Session API change (2/8)) - #159792 (A more readable debug map for IndexMaps) - #161895 (std::sys::pal::sgx: fix mismatched alloc/free alignment) - #161900 (bootstrap: Include feature-gated items in bootstrap tool docs) - #161940 (Promote `wasm32-wasip3` to a tier 2 target) - #162072 (Add new Tier-3 target: `powerpc64-sony-ps3`) - #162179 (type system const items via direct rhs) - #162277 (Introduce `rustc_middle::middel::resolve`) - #162285 (box: fixup map/try_map deallocate calls) - #162286 (string: don't unwind prematurely) - #162289 (alloc: a bunch of safety comments) - #162292 (Update `askama` version to `0.16.1`) - #160509 (Remove `RegionExt`; move methods to `Region` in `rustc_type_ir`) - #160906 (Suggest usize instead of placeholder type for array length constants) - #160936 (traits: Represent live alias arguments as bitsets) - #161400 (Improve diagnostics for references to closures) - #161656 (Suggest mutable references for FnMut closure arguments) - #161711 (Add more splat fn type tests) - #161786 (Make `tcx.def_id_partial_cmp` public) - #161953 (sanitizers: Implicitly disable mutually exclusive sanitizers) - #162155 (add suggestion for `rustc_allowed_through_unstable_modules` attribute) - #162212 (Implement `Rng` for `Box`) - #162246 (Fix incorrect meta span) - #162266 (std: fix typo) - #162291 (Add regression test from 1.98.1)

GuillaumeGomez · 2026-09-04T14:54:51Z

I think it's the one which broke in #162298 (comment).

Lot of errors like:

error[E0725]: the feature `rustc_private` is not in the list of allowed features
 --> /rustc/cce05538c14655b12f69e264c494b616bf3eff7c/src/tools/rustfmt/src/lib.rs:1:12
  |
1 | #![feature(rustc_private)]
  |            ^^^^^^^^^^^^^

@bors r-

rust-bors · 2026-09-04T14:55:00Z

This pull request was unapproved.

This PR was contained in a rollup (#162298), which was unapproved.

View changes since this unapproval

Zalathar · 2026-09-04T15:32:44Z

@bors try jobs=dist-x86_64-linux-alt

bootstrap: Include feature-gated items in bootstrap tool docs try-job: dist-x86_64-linux-alt

rust-bors · 2026-09-04T15:32:51Z

⌛ Trying commit 8f1843d with merge 93dc89f…

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

Workflow: https://github.com/rust-lang/rust/actions/runs/33890102370

Zalathar · 2026-09-04T15:41:34Z

+
+    // Tell rustdoc to document which items require feature flags.
+    cargo.arg("--all-features");
+    cargo.allow_features("doc_cfg");


Ah, the problem is that if a tool_doc! entry doesn't specify a list of allowed features, then this line has the side-effect of disallowing all features other than doc_cfg.

View changes since the review

This sets `--all-features` when documenting bootstrap tool crates, and enables rustdoc's `#![feature(doc_cfg)]` to display which items are feature-gated.

Zalathar · 2026-09-04T15:48:04Z

@bors try cancel
@bors try jobs=dist-x86_64-linux-alt

rust-bors · 2026-09-04T15:48:08Z

Try build cancelled. Cancelled workflows:

https://github.com/rust-lang/rust/actions/runs/33890102370

Hint: if you want to run another try build, you do not need to manually cancel the previous one. Just run @bors try and bors will cancel the previous build automatically.

rust-bors · 2026-09-04T15:48:12Z

⌛ Trying commit 8f4106c with merge ca57196…

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

Workflow: https://github.com/rust-lang/rust/actions/runs/33891566707

bootstrap: Include feature-gated items in bootstrap tool docs try-job: dist-x86_64-linux-alt

rust-bors · 2026-09-04T21:49:40Z

💥 Test timed out after 21600s

Zalathar · 2026-09-04T23:23:57Z

@bors try jobs=dist-x86_64-linux-alt

rust-bors · 2026-09-04T23:24:03Z

⌛ Trying commit 8f4106c with merge 67e4f70…

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

Workflow: https://github.com/rust-lang/rust/actions/runs/33929355839

bootstrap: Include feature-gated items in bootstrap tool docs try-job: dist-x86_64-linux-alt

rust-bors · 2026-09-05T05:29:55Z

💥 Test timed out after 21600s

Zalathar · 2026-09-05T05:38:13Z

Weird that this keeps happening.

@bors try jobs=dist-x86_64-linux-alt

rust-bors · 2026-09-05T05:38:20Z

⌛ Trying commit 8f4106c with merge 3ec43f9…

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

Workflow: https://github.com/rust-lang/rust/actions/runs/33947733260

bootstrap: Include feature-gated items in bootstrap tool docs try-job: dist-x86_64-linux-alt

rustbot added the S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. label Aug 28, 2026

rustbot assigned Mark-Simulacrum Aug 28, 2026

rustbot added the T-bootstrap Relevant to the bootstrap subteam: Rust's build system (x.py and src/bootstrap) label Aug 28, 2026

This comment has been minimized.

Sign in to view

Zalathar force-pushed the tool-doc branch from a82da26 to 7084579 Compare August 28, 2026 04:29

rustbot assigned Kobzol and unassigned Mark-Simulacrum Aug 28, 2026

rustbot added S-blocked Status: Blocked on something else such as an RFC or other implementation work. and removed S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. labels Sep 2, 2026

This comment has been minimized.

Sign in to view

Extract most of tool_doc! into non-macro code

380e552

Zalathar force-pushed the tool-doc branch from 7084579 to 8f1843d Compare September 4, 2026 07:37

rustbot added S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. and removed S-blocked Status: Blocked on something else such as an RFC or other implementation work. labels Sep 4, 2026

rust-bors Bot added the S-waiting-on-bors Status: Waiting on bors to run and complete tests. Bors will change the label on completion. label Sep 4, 2026

rust-bors Bot removed the S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. label Sep 4, 2026

JonathanBrouwer mentioned this pull request Sep 4, 2026

Rollup of 13 pull requests #162293

Closed

GuillaumeGomez mentioned this pull request Sep 4, 2026

Rollup of 25 pull requests #162297

Closed

GuillaumeGomez mentioned this pull request Sep 4, 2026

Rollup of 25 pull requests #162298

Closed

rust-bors Bot added S-waiting-on-author Status: This is awaiting some action (such as code changes or more information) from the author. and removed S-waiting-on-bors Status: Waiting on bors to run and complete tests. Bors will change the label on completion. labels Sep 4, 2026

rust-bors Bot pushed a commit that referenced this pull request Sep 4, 2026

Auto merge of #161900 - Zalathar:tool-doc, r=<try>

93dc89f

bootstrap: Include feature-gated items in bootstrap tool docs try-job: dist-x86_64-linux-alt

Zalathar commented Sep 4, 2026

View reviewed changes

Include feature-gated items in bootstrap tool docs

8f4106c

This sets `--all-features` when documenting bootstrap tool crates, and enables rustdoc's `#![feature(doc_cfg)]` to display which items are feature-gated.

Zalathar force-pushed the tool-doc branch from 8f1843d to 8f4106c Compare September 4, 2026 15:47

rust-bors Bot pushed a commit that referenced this pull request Sep 4, 2026

Auto merge of #161900 - Zalathar:tool-doc, r=<try>

ca57196

bootstrap: Include feature-gated items in bootstrap tool docs try-job: dist-x86_64-linux-alt

rust-bors Bot pushed a commit that referenced this pull request Sep 4, 2026

Auto merge of #161900 - Zalathar:tool-doc, r=<try>

67e4f70

bootstrap: Include feature-gated items in bootstrap tool docs try-job: dist-x86_64-linux-alt

rust-bors Bot pushed a commit that referenced this pull request Sep 5, 2026

Auto merge of #161900 - Zalathar:tool-doc, r=<try>

3ec43f9

bootstrap: Include feature-gated items in bootstrap tool docs try-job: dist-x86_64-linux-alt

Uh oh!

Uh oh!

Conversation

Zalathar commented Aug 28, 2026 • edited by rustbot Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Uh oh!

rustbot commented Aug 28, 2026

Uh oh!

Zalathar commented Aug 28, 2026

Uh oh!

Zalathar commented Aug 28, 2026

Uh oh!

This comment has been minimized.

Zalathar commented Aug 28, 2026

Uh oh!

Kobzol commented Aug 28, 2026

Uh oh!

Kobzol commented Aug 28, 2026

Uh oh!

Zalathar commented Aug 28, 2026

Uh oh!

Zalathar commented Aug 28, 2026

Uh oh!

Kobzol commented Aug 28, 2026

Uh oh!

Zalathar commented Sep 2, 2026

Uh oh!

This comment has been minimized.

rustbot commented Sep 4, 2026

Uh oh!

Zalathar commented Sep 4, 2026

Uh oh!

Kobzol commented Sep 4, 2026

Uh oh!

Zalathar commented Sep 4, 2026

Uh oh!

rust-bors Bot commented Sep 4, 2026

Uh oh!

GuillaumeGomez commented Sep 4, 2026

Uh oh!

rust-bors Bot commented Sep 4, 2026

Uh oh!

Zalathar commented Sep 4, 2026

Uh oh!

rust-bors Bot commented Sep 4, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Uh oh!

Zalathar Sep 4, 2026 • edited by rustbot Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Zalathar commented Sep 4, 2026

Uh oh!

rust-bors Bot commented Sep 4, 2026

Uh oh!

rust-bors Bot commented Sep 4, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Uh oh!

rust-bors Bot commented Sep 4, 2026

Uh oh!

Zalathar commented Sep 4, 2026

Uh oh!

rust-bors Bot commented Sep 4, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Uh oh!

rust-bors Bot commented Sep 5, 2026

Uh oh!

Zalathar commented Sep 5, 2026

Uh oh!

rust-bors Bot commented Sep 5, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

6 participants

Zalathar commented Aug 28, 2026 •

edited by rustbot

Loading

rust-bors Bot commented Sep 4, 2026 •

edited

Loading

Zalathar Sep 4, 2026 •

edited by rustbot

Loading

rust-bors Bot commented Sep 4, 2026 •

edited

Loading

rust-bors Bot commented Sep 4, 2026 •

edited

Loading

rust-bors Bot commented Sep 5, 2026 •

edited

Loading