Merge `compiler-builtins` as a Josh subtree
Use the Josh [1] utility to add `compiler-builtins` as a subtree, which
will allow us to stop using crates.io for updates. This is intended to
help resolve some problems when unstable features change and require
code changes in `compiler-builtins`, which sometimes gets trapped in a
bootstrap cycle.
This was done using `josh-filter` built from the r24.10.04 tag:
git fetch https://github.com/rust-lang/compiler-builtins.git 233434412fe7eced8f1ddbfeddabef1d55e493bd
josh-filter ":prefix=library/compiler-builtins" FETCH_HEAD
git merge --allow-unrelated FILTERED_HEAD
The HEAD in the `compiler-builtins` repository is 233434412f ("fix an if
statement that can be collapsed").
[1]: https://github.com/josh-project/josh
Use ccache for stage0 tool builds
Now after the stage0 redesign, we can actually start ccaching the build of the compiler itself. We can also cache the bootstrap tools, since these are also built with the stage0 compiler.
Stage0 compiler builds are now being cached: https://github.com/rust-lang/rust/actions/runs/15397246267#summary-43321151192 (`..bootstrap::core::build_steps::compile::Rustc 483.10s 40.41s -91.6%`). It's not a gigantic win everywhere, but it should help. It seems to make the Linux jobs ~10 minute faster. It should be especially useful on PR builds after https://github.com/rust-lang/rust/pull/141948.
r? `@jieyouxu`
try-job: `x86_64-gnu-llvm-19*`
try-job: `x86_64-msvc*`
try-job: `x86_64-apple*`
try-job: `dist-x86_64-linux`
Deconstruct values in the THIR visitor
I continue to add deconstruction for task rust-lang/rust#141849
The changes concern a more complex part of the task `compiler/rustc_hir/src/intravisit.rs`
r? `@nnethercote`
Update books
## rust-lang/book
4 commits in 230c68bc1e08f5f3228384a28cc228c81dfbd10d..634724ea85ebb08a542970bf8871ac8b0f77fd15
2025-05-29 13:16:14 UTC to 2025-05-22 21:35:03 UTC
- Chapter 10 from tech review (rust-lang/book#4379)
- Chapter 9 from tech review (rust-lang/book#4377)
- Chapter 8 from tech review (rust-lang/book#4378)
- Chapter 7 from tech review (rust-lang/book#4374)
## rust-embedded/book
3 commits in 0b8219ac23a3e09464e4e0166c768cf1c4bba0d5..10fa1e084365f23f24ad0000df541923385b73b6
2025-05-27 18:37:30 UTC to 2025-05-27 18:26:36 UTC
- portability: add reference to embedded-hal docs (rust-embedded/book#391)
- remove the unused and deprecated `multilingual` field from `book.toml` (rust-embedded/book#388)
- Ci upgrade 20250522 (rust-embedded/book#393)
## rust-lang/nomicon
4 commits in c76a20f0d987145dcedf05c5c073ce8d91f2e82a..8b61acfaea822e9ac926190bc8f15791c33336e8
2025-05-26 10:16:09 UTC to 2025-05-23 15:03:00 UTC
- Use inline const expression in unchecked-uninit.md (rust-lang/nomicon#492)
- Fix code sample output in unchecked-uninit.md (rust-lang/nomicon#491)
- Use consistent type parameters in subtyping.md (rust-lang/nomicon#493)
- Fix typo in atomics.md (rust-lang/nomicon#494)
## rust-lang/reference
1 commits in 118fd1f1f0854f50e3ae1fe4b64862aad23009ca..8e0f593a30f3b56ddb0908fb7ab9249974e08738
2025-05-31 20:12:39 UTC to 2025-05-31 20:12:39 UTC
- Minor fixes to `$crate` behavior (rust-lang/reference#1816)
## rust-lang/rust-by-example
4 commits in c9d151f9147c4808c77f0375ba3fa5d54443cb9e..21f4e32b8b40d36453fae16ec07ad4b857c445b6
2025-05-29 12:45:08 UTC to 2025-05-29 12:44:23 UTC
- Update book.toml rename `author` field to `authors` (rust-lang/rust-by-example#1917)
- Add example to comment.md to teach how to toggle a whole code block using block comments (rust-lang/rust-by-example#1919)
- The example is not meant to be compiled with out passing arguments. (rust-lang/rust-by-example#1930)
- added a shorthand for the #[should_panic(expected = "msg") (rust-lang/rust-by-example#1931)
Deconstruct values in the THIR visitor
Hi! I am a beginner rust developer.
I'm trying to solve your problem rust-lang/rust#141849
I see that 2 files need to be corrected, so I’m starting with a simpler step, `compiler/rustc_middle/src/thir/visit.rs`
r? `@krikera`
Switch `x86_64-msvc-{1,2}` back to Windows Server 2025 images
New Windows Server 2025 images have been released (**20250527.1.0**). New images appear to not exhibit the lack-of-disk-space problem as tracked by rust-lang/rust#141022, and the new runner image's storage capacity appears to be configured correctly.
Windows Server 2025 image version **20250527.1.0** release notes: <https://github.com/actions/runner-images/releases/tag/win25%2F20250527.1>.
Resolvesrust-lang/rust#141022.
`tests/ui`: A New Order [2/N]
part of rust-lang/rust#133895
r? `@jieyouxu`
let's try this kind of commits, one for each file, commit's name shows what i did, hope this is not harder to review than previous
fix(#141141): When expanding `PartialEq`, check equality of scalar types first.
Fixesrust-lang/rust#141141.
Now, `cs_eq` function of `partial_eq.rs` compares [scalar types](https://doc.rust-lang.org/rust-by-example/primitives.html#scalar-types) first.
- Add `is_scalar` field to `FieldInfo`.
- Add `is_scalar` method to `TyKind`.
- Pass `FieldInfo` via `CsFold::Combine` and refactor code relying on it.
- Implement `TryFrom<&str>` and `TryFrom<Symbol>` for FloatTy.
- Implement `TryFrom<&str>` and `TryFrom<Symbol>` for IntTy.
- Implement `TryFrom<&str>` and `TryFrom<Symbol>` for UintTy.
Rollup of 9 pull requests
Successful merges:
- rust-lang/rust#141554 (Improve documentation for codegen options)
- rust-lang/rust#141817 (rustc_llvm: add Windows system libs only when cross-compiling from Wi…)
- rust-lang/rust#141843 (Add `visit_id` to ast `Visitor`)
- rust-lang/rust#141881 (Subtree update of `rust-analyzer`)
- rust-lang/rust#141898 ([rustdoc-json] Implement PartialOrd and Ord for rustdoc_types::Id)
- rust-lang/rust#141921 (Disable f64 minimum/maximum tests for arm 32)
- rust-lang/rust#141930 (Enable triagebot `[concern]` functionality)
- rust-lang/rust#141936 (Decouple "reporting in deps" from `FutureIncompatibilityReason`)
- rust-lang/rust#141949 (move `test-float-parse` tool into `src/tools` dir)
r? `@ghost`
`@rustbot` modify labels: rollup
Decouple "reporting in deps" from `FutureIncompatibilityReason`
The reason should just be it -- the reason. It never felt right to me that it was also responsible for whatever we include the warning in cargo's reports.
It gets especially unruly if you want to add non-`FutureReleaseError*` warnings which are included in the reports.
I just added a field to `FutureIncompatibleInfo` to control whatever the diagnostic is included in the cargo's reports.
Disable f64 minimum/maximum tests for arm 32
This disables the f64 minimum/maximum tests for the arm-unknown-linux-gnueabihf job. The next release will be supporting cross-compiled doctests, and these tests fail on that platform.
It looks like this was just fixed via https://github.com/llvm/llvm-project/pull/142170, but I assume that will not trickle down to our copy of llvm in the next couple of weeks. Assuming that does get fixed when llvm is updated, then these can be removed.
cc https://github.com/rust-lang/rust/issues/141087
[rustdoc-json] Implement PartialOrd and Ord for rustdoc_types::Id
This allows consumers to create collections that required an ordering relationship for their keys—e.g. a `BTreeMap`.
Add `visit_id` to ast `Visitor`
This helps with efforts to deduplicate the `MutVisitor` and the `Visitor` code. All users of `Visitor`'s methods that have extra `NodeId` as parameters really just want to visit the id on its own.
Also includes some methods deduplicated and cleaned up as a result of this change.
r? oli-obk
Improve documentation for codegen options
This adds more information to many different codegen options. It should not add any new guarantees, just document existing behavior.
r? bjorn3
Fix borrowck mentioning a name from an external macro we (deliberately) don't save
Most of the info is already in the title 🤷Closesrust-lang/rust#141764
Don't declare variables in `ExprKind::Let` in invalid positions
Handle `let` expressions in invalid positions specially during resolve in order to avoid making destructuring-assignment expressions that reference (invalid) variables that have not yet been delcared yet.
See further explanation in test and comment in the source.
Fixesrust-lang/rust#141844
Async drop - type instead of async drop fn, fixes#140484Fixes: rust-lang/rust#140484Fixes: rust-lang/rust#140500
Fixes ICE, when type is provided in AsyncDrop trait instead of `async fn drop()`.
Fixes ICE, when async drop fn has wrong signature.
Clarify &mut-methods' docs on sync::OnceLock
Three small changes to the docs of `sync::OnceLock`:
* The docs for `OnceLock::take()` used to [say](https://doc.rust-lang.org/std/sync/struct.OnceLock.html#method.take) "**Safety** is guaranteed by requiring a mutable reference." (emphasis mine). While technically correct, imho its not necessary to even mention safety - as opposed to unsafety - here: Safety never comes up wrt `OnceLock`, as there is (currently) no way to interact with a `OnceLock` in an unsafe way; there are no unsafe methods on `OnceLock`, so there is "safety" guarantee required anywhere. What we simply meant to say is "**Synchronization** is guaranteed...".
* I've add that phrase to the other methods of `OnceLock` which take a `&mut self`, to highlight the fact that having a `&mut OnceLock` guarantees that synchronization with other threads is not required. This is the same as with [`Mutex::get_mut()`](https://doc.rust-lang.org/std/sync/struct.Mutex.html#method.get_mut), [`Cell::get_mut()`](https://doc.rust-lang.org/std/cell/struct.Cell.html#method.get_mut), and others.
* In that spirit, the half-sentence "or being initialized" was removed from `get_mut()`, as there is no way that the `OnceLock` is being initialized while we are holding `&mut` to it. Probably a copy&paste from `.get()`
tools-aux ci runner: also cross-test doctests in Miri
Miri now supports running doctests across different targets. Let's use that to run the std doctests on aarch64-apple-darwin, i686-pc-windows-msvc.
try-job: x86_64-gnu-aux
compiler-builtins has a symlink to the `libm` source directory so the
two crates can share files but still act as two separate crates. This
causes problems with some sysroot-related tooling, however, since
directory symlinks seem to not be supported.
The reason this was a symlink in the first place is that there isn't an
easy for Cargo to publish two crates that share source (building works
fine but publishing rejects `include`d files from parent directories, as
well as nested package roots). However, after the switch to a subtree,
we no longer need to publish compiler-builtins; this means that we can
eliminate the link and just use `#[path]`.
Similarly, the LICENSE file was symlinked so it could live in the
repository root but be included in the package. This is also removed as
it caused problems with the dist job (error from bootstrap's
`tarball.rs`, "generated a symlink in a tarball").
If we need to publish compiler-builtins again for any reason, it would
be easy to revert these changes in a preprocess step.
Warn when gold was used as the linker
gold has been deprecated recently and is known to behave incorrectly around Rust programs, including miscompiling `#[used(linker)]`. Tell people to switch to a different linker instead.
closesrust-lang/rust#141748
r? bjorn3
`UsePath` contains a `SmallVec<[Res; 3]>`. This holds up to three `Res`
results, one per namespace (type, value, or macro). `lower_import_res`
takes a `PerNS<Option<Res<NodeId>>>` result and lowers it into the
`SmallVec`. This is pretty weird. The input `PerNS` makes it clear which
`Res` belongs to which namespace, but the `SmallVec` throws that
information away.
And code that operates on the `SmallVec` tends to use iteration (or even
just grabbing the first entry!) without knowing which namespace the
`Res` belongs to. Even weirder! Also, `SmallVec` is an overly flexible
type to use here, because it can contain any number of elements (even
though it's optimized for 3 in this case).
This commit changes `UsePath` so it also contains a
`PerNS<Option<Res<HirId>>>`. This type preserves more information and is
more self-documenting. The commit also changes a lot of the use sites to
access the result for a particular namespace. E.g. if you're looking up
a trait, it will be in the `Res` for the type namespace if it's present;
it's silly to look in the `Res` for the value namespace or macro
namespace. Overall I find the new code much easier to understand.
However, some use sites still iterate. These now use `present_items`
because that filters out the `None` results.
Also, `redundant_pub_crate.rs` gets a bigger change. A
`UseKind:ListStem` item gets no `Res` results, which means the old `all`
call in `is_not_macro_export` would succeed (because `all` succeeds on
an empty iterator) and the `ListStem` would be ignored. This is what we
want, but was more by luck than design. The new code detects `ListStem`
explicitly. The commit generalizes the name of that function
accordingly.
Finally, the commit also removes the `use_path` arena, because
`PerNS<Option<Res>>` impls `Copy` (unlike `SmallVec`) and it can be
allocated in the arena shared by all `Copy` types.
