docs: autogenerate compiler flag stubs based on -Zhelp #142135

rmehri01 · 2025-06-07T01:53:32Z

Adds autogenerated compiler flag stubs to the unstable book by building rustc, passing it's path to unstable-book-gen, and using that to call the compiler with -Zhelp and create a similar Features that is used for library and lang stubs.

Example:

# `combine_cgu`

combine CGUs into a single one

This feature has no tracking issue, and is therefore likely internal to the compiler, not being intended for general use.

------------------------

Closes #141525

rustbot · 2025-06-07T01:53:36Z

Failed to set assignee to jyn514: invalid assignee

Note: Only org members with at least the repository "read" role, users with write permissions, or people who have commented on the PR may be assigned.

rustbot · 2025-06-07T02:03:03Z

Error: Parsing assign command in comment failed: ...'' | error: specify user to assign to at >| ''...

Please file an issue on GitHub at triagebot if there's a problem with this bot, or reach out on #t-infra on Zulip.

workingjubilee · 2025-06-07T02:14:13Z

r? compiler

lcnr · 2025-06-10T13:25:50Z

r? compiler

compiler-errors · 2025-06-11T23:25:00Z

@bors r+

bors · 2025-06-11T23:25:04Z

📌 Commit 2cfd494 has been approved by compiler-errors

It is now in the queue for this repository.

…piler-errors docs: autogenerate compiler flag stubs based on -Zhelp Adds autogenerated compiler flag stubs to the unstable book by building rustc, passing it's path to `unstable-book-gen`, and using that to call the compiler with `-Zhelp` and create a similar `Features` that is used for library and lang stubs. Example: ```md # `combine_cgu` combine CGUs into a single one This feature has no tracking issue, and is therefore likely internal to the compiler, not being intended for general use. ------------------------ ``` Closes rust-lang#141525

Rollup of 9 pull requests Successful merges: - #138016 (Added `Clone` implementation for `ChunkBy`) - #140770 (add `extern "custom"` functions) - #141162 (refactor `AttributeGate` and `rustc_attr!` to emit notes during feature checking) - #141474 (Add `ParseMode::Diagnostic` and fix multiline spans in diagnostic attribute lints) - #141947 (Specify that "option-like" enums must be `#[repr(Rust)]` to be ABI-compatible with their non-1ZST field.) - #142135 (docs: autogenerate compiler flag stubs based on -Zhelp) - #142252 (Improve clarity of `core::sync::atomic` docs about "Considerations" in regards to CAS operations) - #142337 (miri: add flag to suppress float non-determinism) - #142353 (compiler: Ease off the accelerator on `unsupported_calling_conventions`) r? `@ghost` `@rustbot` modify labels: rollup

matthiaskrgr · 2025-06-12T11:30:17Z

@bors r-
guess this failed here #142399 (comment)

alex-semenyuk · 2025-08-09T19:45:34Z

@rmehri01
Thanks for your contribution.
Form wg-triage. Any updates on this PR?

rmehri01 · 2025-08-09T20:17:44Z

@rmehri01 Thanks for your contribution. Form wg-triage. Any updates on this PR?

Hey! Sorry I'm not exactly sure what went wrong here, it seems like it has to do something with getting the output of -Zhelp on aarch64 windows, is there something else we should try instead?

Edit: nvm I think I messed up the host argument to builder.compiler

rmehri01 · 2025-08-09T23:46:19Z

@rustbot review

bors · 2025-08-10T18:29:12Z

☔ The latest upstream changes (presumably #145210) made this pull request unmergeable. Please resolve the merge conflicts.

bors · 2025-08-11T09:47:17Z

☔ The latest upstream changes (presumably #145011) made this pull request unmergeable. Please resolve the merge conflicts.

compiler-errors · 2025-08-14T17:03:37Z

r? bootstrap

src/bootstrap/src/core/build_steps/doc.rs

Mark-Simulacrum · 2025-08-21T01:22:34Z

src/tools/unstable-book-gen/src/main.rs


+fn collect_compiler_flags(rustc_path: impl AsRef<Path>) -> Features {
+    let mut rustc = Command::new(rustc_path.as_ref());
+    rustc.arg("-Zhelp");


Rather than running -Zhelp and then trying to parse that, maybe we can parse the options! macro (

rust/compiler/rustc_session/src/options.rs

Line 2116 in 040a98a

options! {

)? I think that has all the -Z flags. That would also give you a file/line to link to. I'm not sure how valuable that is, but if it is, that seems like the way to get that information.

I'm OK with sticking with -Z/-C parsing since the syntax is both fairly simple and controlled by us, though.

We'd likely also want (perhaps in a separate PR) to enforce that all the -C flags in codegen options (also in the linked file) have documentation in the non-unstable book. That could be done in tidy.

It would probably be nice to have the file/line to link to, do you mean just literally reading and parsing the rust source file to do that or is there a better way to go about it?

bors · 2025-09-21T17:05:28Z

☔ The latest upstream changes (presumably #146592) made this pull request unmergeable. Please resolve the merge conflicts.

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 Jun 7, 2025

rustbot added the T-compiler Relevant to the compiler team, which will review and decide on the PR/issue. label Jun 7, 2025

rustbot assigned lcnr Jun 7, 2025

This comment has been minimized.

Sign in to view

rmehri01 force-pushed the gen-compiler-flags branch from 42a4c2d to 2cfd494 Compare June 7, 2025 02:26

rustbot assigned compiler-errors and unassigned lcnr Jun 10, 2025

compiler-errors approved these changes Jun 11, 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 Jun 11, 2025

workingjubilee mentioned this pull request Jun 12, 2025

Rollup of 15 pull requests #142396

Closed

workingjubilee mentioned this pull request Jun 12, 2025

Rollup of 15 pull requests #142397

Closed

matthiaskrgr mentioned this pull request Jun 12, 2025

Rollup of 9 pull requests #142399

Closed

bors 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 Jun 12, 2025

This comment has been minimized.

Sign in to view

rmehri01 force-pushed the gen-compiler-flags branch from bc500ae to 00ce4f5 Compare August 9, 2025 20:49

This comment has been minimized.

Sign in to view

rmehri01 force-pushed the gen-compiler-flags branch from bd8cdf2 to 0e7711e Compare August 9, 2025 21:33

rustbot added S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. and removed S-waiting-on-author Status: This is awaiting some action (such as code changes or more information) from the author. labels Aug 9, 2025

rmehri01 force-pushed the gen-compiler-flags branch from 0e7711e to 8e0034d Compare August 10, 2025 18:42

This comment has been minimized.

Sign in to view

rmehri01 force-pushed the gen-compiler-flags branch 2 times, most recently from d633a45 to 91ee21b Compare August 10, 2025 19:42

rmehri01 force-pushed the gen-compiler-flags branch from 91ee21b to 3104e57 Compare August 11, 2025 12:53

rustbot assigned Mark-Simulacrum and unassigned compiler-errors Aug 14, 2025

Mark-Simulacrum reviewed Aug 21, 2025

View reviewed changes

Mark-Simulacrum 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-review Status: Awaiting review from the assignee but also interested parties. labels Aug 21, 2025

rmehri01 added 2 commits August 23, 2025 09:03

docs: autogenerate compiler flag stubs based on -Zhelp

e873ba2

update snapshot tests

41eb772

rmehri01 force-pushed the gen-compiler-flags branch from 3104e57 to 41eb772 Compare August 23, 2025 13:04

rmehri01 closed this Oct 11, 2025

rustbot removed the S-waiting-on-author Status: This is awaiting some action (such as code changes or more information) from the author. label Oct 11, 2025

docs: autogenerate compiler flag stubs based on -Zhelp #142135

docs: autogenerate compiler flag stubs based on -Zhelp #142135

Uh oh!

Conversation

rmehri01 commented Jun 7, 2025 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Uh oh!

rustbot commented Jun 7, 2025

Uh oh!

rustbot commented Jun 7, 2025

Uh oh!

workingjubilee commented Jun 7, 2025

Uh oh!

This comment has been minimized.

lcnr commented Jun 10, 2025

Uh oh!

compiler-errors commented Jun 11, 2025

Uh oh!

bors commented Jun 11, 2025

Uh oh!

matthiaskrgr commented Jun 12, 2025

Uh oh!

alex-semenyuk commented Aug 9, 2025

Uh oh!

rmehri01 commented Aug 9, 2025 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Uh oh!

This comment has been minimized.

This comment has been minimized.

This comment has been minimized.

This comment has been minimized.

rmehri01 commented Aug 9, 2025

Uh oh!

bors commented Aug 10, 2025

Uh oh!

This comment has been minimized.

bors commented Aug 11, 2025

Uh oh!

compiler-errors commented Aug 14, 2025

Uh oh!

Uh oh!

Uh oh!

Mark-Simulacrum Aug 21, 2025

Choose a reason for hiding this comment

Uh oh!

rmehri01 Aug 23, 2025

Choose a reason for hiding this comment

Uh oh!

bors commented Sep 21, 2025

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

11 participants

rmehri01 commented Jun 7, 2025 •

edited

Loading

rmehri01 commented Aug 9, 2025 •

edited

Loading