Implement unstable trait impl
This PR allows marking impls of stable trait with stable type as unstable.
## Approach
In std/core, an impl can be marked as unstable by annotating it with ``#[unstable_feature_bound(feat_name)]``. This will add a ``ClauseKind::Unstable_Feature(feat_name)`` to the list of predicates in ``predicates_of`` .
When an unstable impl's function is called, we will first iterate through all the goals in ``param_env`` to check if there is any ``ClauseKind::UnstableFeature(feat_name)`` in ``param_env``.
The existence of ``ClauseKind::Unstable_Feature(feat_name)`` in ``param_env`` means an``#[unstable_feature_bound(feat_name)]`` is present at the call site of the function, so we allow the check to succeed in this case.
If ``ClauseKind::UnstableFeature(feat_name)`` does not exist in ``param_env``, we will still allow the check to succeed for either of the cases below:
1. The feature is enabled through ``#[feature(feat_name)]`` outside of std / core.
2. We are in codegen because we may be monomorphizing a body from an upstream crate which had an unstable feature enabled that the downstream crate do not.
For the rest of the case, it will fail with ambiguity.
## Limitation
In this PR, we do not support:
1. using items that need ``#[unstable_feature_bound]`` within stable APIs
2. annotate main function with ``#[unstable_feature_bound]``
3. annotate ``#[unstable_feature_bound]`` on items other than free function and impl
## Acknowledgement
The design and mentoring are done by `@BoxyUwU`
Add tracing to `InterpCx::fn_abi_of_instance/fn_abi_of_fn_ptr`
This PR adds tracing to the `InterpCx::fn_abi_of_instance`/`::fn_abi_of_fn_ptr` functions by shadowing `FnAbiOf`'s trait methods with inherent methods on `InterpCx`, like done in rust-lang/rust#142721. The reason why I am targeting these two functions is because they are used for Miri interpretation, and they make a `layout_of` query down the line without passing through the `layout_of` that was traced in rust-lang/rust#142721.
There are other places where `layout_of` is called without being traced (see the analysis below), but that's because the `Machine` used there is not `MiriMachine` but rather `CompileTimeMachine` which does not implement `enter_trace_span()`. But after discussing with ```````@RalfJung``````` we agreed that the const-eval part should not be traced together with Miri, that's why I am ignoring the other places where `layout_of` is called.
r? ```````@RalfJung```````
<details><summary>Analysis of the places where <code>layout_of</code> is called</summary>
I did some analysis for https://github.com/rust-lang/rust/pull/142721#discussion_r2171494841, and these are all the places where the query `tcx.layout_of` is called (directly or indirectly) outside of a traced `InterpCx::layout_of` while a program is being interpreted by Miri:
```
adjust_for_rust_scalar at ./compiler/rustc_ty_utils/src/abi.rs:302:35
{closure#2} at ./compiler/rustc_ty_utils/src/abi.rs:522:25
eval_body_using_ecx<> at ./compiler/rustc_const_eval/src/const_eval/eval_queries.rs:49:22
{closure#1}<> at ./compiler/rustc_const_eval/src/interpret/operand.rs:851:76
{closure#0}<> at ./compiler/rustc_const_eval/src/interpret/stack.rs:612:18
size_and_align at ./compiler/rustc_middle/src/mir/interpret/mod.rs:387:38
```
I got these by:
- patching rustc with this patch that adds a span to the `layout_of` query which prints the backtrace:
[layout_of_other_places.diff.txt](https://github.com/user-attachments/files/21235523/layout_of_other_places.diff.txt)
- adding this to my bootstrap.toml to have debug symbols inside the Miri binary: `rust.debuginfo-level = "line-tables-only"` and also `build.tool.miri.features = ["tracing"]`
- obtaining a trace file with `MIRI_TRACING=1 ./x.py run miri --stage 1 --warnings warn --args src/tools/miri/tests/pass/hello.rs` (note: maybe using a file different than "src/tools/miri/tests/pass/hello.rs" would lead to more places where layout_of is called?)
- running this query in Perfetto to select all `layout_of` spans that have as a direct parent a span named "frame" (as opposed to the parent being `InterpCx::layout_of`) and extract their backtrace: `select args.string_value from slice left join args on slice.arg_set_id = args.id where slice.name = "tcx.layout_of" and slice.parent_id in (select slice2.id from slice as slice2 where slice2.name = "frame") group by args.string_value`
- exporting the data as `.tsv` and processing that file through this Python script. It finds the first path in the backtraces where "layout" isn't mentioned, which imo is a good heuristic to not consider `layout_of` wrappers/friends as call places, but rather go down the backtrace until an actual call place is reached. [layout_of_other_places.py.txt](https://github.com/user-attachments/files/21235529/layout_of_other_places.py.txt)
</details>
tidy: check for invalid file names
Check for file names added to git with:
- non-UTF8 filenames (this would fail "fmt check" with a decoding error for the moment, but maybe we should not count on it as it is an accidental failure)
- control characters (such as "\n" or "\r" in file names)
- ":" (which is a special character on Windows, made rust-lang/rust#142936 fail in bors while it could have be caught earlier)
It only checks files known by git as a developer might want to have "strange" file names alongside their local repository as long as they don't check them in.
r? jieyouxu
as he stumbled upon such a file in rust-lang/rust#142936
Constify `Index` traits
tracking issue: rust-lang/rust#143775
the `SliceIndex` trait cannot be implemented by users as it is sealed. While it would be useful for the `get` method on slices, it seems weird to have a feature gate for that that isn't also gating index syntax at the same time, so I put them under the same feature gate.
r? ```````@fee1-dead```````
Move several float tests to floats/mod.rs
This PR moves several tests to `floats/mod.rs`, as discussed in https://github.com/rust-lang/rust/issues/141726. The tests moved are:
- `test_num_f*`
- `test_infinity`
- `test_neg_infinity`
- `test_zero`
- `test_neg_zero`
- `test_one`
- `test_is_nan`
- `test_is_infinite`
- `test_is_finite`
- `test_is_normal`
- `test_classify`
Each test is its own commit, so it may be easiest to review each commit individually.
r? tgross35
remote-test-client: Exit code `128 + <signal-number>` instead of `3`
If the remote process is terminated by a signal, make `remote-test-client` exit with the code `128 + <signal-number>` instead of always `3`. This follows common practice among tools such as bash [^1]:
> When a command terminates on a fatal signal whose number is N, Bash uses the
> value 128+N as the exit status.
It also allows us to differentiate between `run-pass` and `run-crash` ui tests without special case code in compiletest for that when `remote-test-client` is used. See https://github.com/rust-lang/rust/pull/143002 and in particular https://github.com/rust-lang/rust/pull/143002#issuecomment-3037061667.
Exiting with code `3` has been done from the start (see https://github.com/rust-lang/rust/pull/39400) and seems arbitrary rather than a deliberate design decision, so changing it does not seem like an extraordinarily big deal.
### Regression testing
Note that https://github.com/rust-lang/rust/pull/143002 will act as a regression test once it is rebased on this PR.
### Why a separate PR
I think it is comforting to know that CI does not break with just this change. But if my reviewer prefers, we can move this commit to be part of https://github.com/rust-lang/rust/pull/143002 instead.
[^1]: https://www.gnu.org/software/bash/manual/html_node/Exit-Status.html
wrapping shift: remove first bitmask and table
```rust
#[inline(always)]
pub const fn wrapping_shl(self, rhs: u32) -> Self {
// SAFETY: the masking by the bitsize of the type ensures that we do not shift
// out of bounds
unsafe {
self.unchecked_shl(rhs & (Self::BITS - 1))
}
}
```
already does the bitmask, so it seems unnecessary here.
More context: internals.rust-lang.org/t/wrapping-shift-operator-code-doing-bitmasking-twice/23167
rustdoc-json: Structured attributes
Implements and closesrust-lang/rust#141358.
This has 2 primary benefits.
1. For rustdoc-json consumers, they no longer need to parse strings of attributes, but it's there in a structured and normalized way. CC ```@obi1kenobi```
2. For rustc conributors, the output of HIR pretty printing is no longer a versioned thing in the output. People can work on rust-lang/rust#131229 without needing to bump `FORMAT_VERSION`. CC ```@jdonszelmann``` ```@JonathanBrouwer.```
(Over time, as the attribute refractor continues, I expect we'll add new things to `rustdoc_json_types::Attribute`. But this can be done separately to the rustc changes).
Todo before being mergable:
- [x] Update test assertions.
- [x] Fix modeling of `#[repr]`.
- [ ] ~~Add tests of `#[doc(hidden)]` in `Item::attrs` (probably in a seperate PR).~~ I'm gonna punt this to a future PR
- [x] Documentation.
resolve: Merge `NameBindingKind::Module` into `NameBindingKind::Res`
This is a simplification, but also an optimization, because now we load modules from external crates in a more lazy fashion.
Update cargo
1 commits in eabb4cd923deb73e714f7ad3f5234d68ca284dbe..6833aa715d724437dc1247d0166afe314ab6854e
2025-07-09 22:07:55 +0000 to 2025-07-13 02:25:52 +0000
- Add `[hints]` table in `Cargo.toml`, and a `hints.mostly-unused` hint (rust-lang/cargo#15673)
Implements https://www.github.com/rust-lang/rust/issues/141358.
This has 2 primary benefits:
1. For rustdoc-json consumers, they no longer need to parse strings of
attributes, but it's there in a structured and normalized way.
2. For rustc contributors, the output of HIR pretty printing is no
longer a versioned thing in the output. People can work on
https://github.com/rust-lang/rust/issues/131229 without needing to
bump `FORMAT_VERSION`.
(Over time, as the attribute refractor continues, I expect we'll add new
things to `rustdoc_json_types::Attribute`. But this can be done
separately to the rustc changes).
`std::vec`: Add UB check for `set_len`, `from_raw_parts_in`, and etc.
Closesrust-lang/rust#143813
I noticed that `from_parts_in` do the similar things like `from_raw_parts_in`, so I add the UB check in the last commit. If it is not appropriate, I will remove it.
And I fix a typo in the first commit.
r? `@scottmcm`
