2617 Commits

Author SHA1 Message Date
Josh Stone d0b5e61fe7 Revert "Stabilize assert_matches"
This reverts commit 2f3b952349.
2026-04-08 14:10:50 -07:00
Josh Stone bca08d8c93 Revert "update diagnostic for variables moved by dbg!"
This reverts commit 1374038f80.
2026-04-08 09:45:54 -07:00
dianne 1374038f80 update diagnostic for variables moved by dbg!
(cherry picked from commit 7d1b41cbb3)
2026-04-02 11:05:25 -07:00
Guillaume Gomez 4803bb96c1 Replace TyCtxt::node_span_lint with emit_node_span_lint in rustc_borrowck 2026-02-26 09:31:29 +01:00
Guillaume Gomez 2bb3b01af2 Replace TyCtxt::emit_node_span_lint with emit_diag_node_span_lint 2026-02-24 20:34:22 +01:00
Guillaume Gomez 119b87fc61 Migrate rustc_borrowck to use TyCtxt::emit_diag_node_span_lint 2026-02-23 11:35:52 +01:00
Nicholas Nethercote a3d590888b Remove impl IntoQueryParam<P> for &'a P.
`IntoQueryParam` is a trait that lets query callers be a bit sloppy with
the passed-in key.
- Types similar to `DefId` will be auto-converted to `DefId`. Likewise
  for `LocalDefId`.
- Reference types will be auto-derefed.

The auto-conversion is genuinely useful; the auto-derefing much less so.
In practice it's only used for passing `&DefId` to queries that accept
`DefId`, which is an anti-pattern because `DefId` is marked with
`#[rustc_pass_by_value]`.

This commit removes the auto-deref impl and makes the necessary sigil
adjustments. (I generally avoid using `*` to deref manually at call
sites, preferring to deref via `&` in patterns or via `*` in match
expressions. Mostly because that way a single deref often covers
multiple call sites.)
2026-02-22 17:58:54 +11:00
Jana Dönszelmann decec173ec remove AttributeKind everywhere 2026-02-20 09:50:16 +01:00
Jana Dönszelmann 63edc913fa change all uses 2026-02-20 09:50:16 +01:00
Jonathan Brouwer 9330931a2b Rollup merge of #152596 - estebank:multipart_suggestions, r=petrochenkov
Make all multipart suggestions verbose

The ShowAlways style of suggestions is usually easier to understand than the inline style.
2026-02-19 10:56:37 +01:00
bors e0cb264b81 Auto merge of #141295 - Kivooeo:if-let-guard-stable, r=fee1-dead,est31
Stabilize `if let` guards (`feature(if_let_guard)`)



## Summary

This proposes the stabilization of `if let` guards (tracking issue: rust-lang/rust#51114, RFC: rust-lang/rfcs#2294). This feature allows `if let` expressions to be used directly within match arm guards, enabling conditional pattern matching within guard clauses.

## What is being stabilized

The ability to use `if let` expressions within match arm guards.

Example:

```rust
enum Command {
    Run(String),
    Stop,
    Pause,
}

fn process_command(cmd: Command, state: &mut String) {
    match cmd {
        Command::Run(name) if let Some(first_char) = name.chars().next() && first_char.is_ascii_alphabetic() => {
            // Both `name` and `first_char` are available here
            println!("Running command: {} (starts with '{}')", name, first_char);
            state.push_str(&format!("Running {}", name));
        }
        Command::Run(name) => {
            println!("Cannot run command '{}'. Invalid name.", name);
        }
        Command::Stop if state.contains("running") => {
            println!("Stopping current process.");
            state.clear();
        }
        _ => {
            println!("Unhandled command or state.");
        }
    }
}
```

## Motivation

The primary motivation for `if let` guards is to reduce nesting and improve readability when conditional logic depends on pattern matching. Without this feature, such logic requires nested `if let` statements within match arms:

```rust
// Without if let guards
match value {
    Some(x) => {
        if let Ok(y) = compute(x) {
            // Both `x` and `y` are available here
            println!("{}, {}", x, y);
        }
    }
    _ => {}
}

// With if let guards
match value {
    Some(x) if let Ok(y) = compute(x) => {
        // Both `x` and `y` are available here
        println!("{}, {}", x, y);
    }
    _ => {}
}
```

## Implementation and Testing

The feature has been implemented and tested comprehensively across different scenarios:

### Core Functionality Tests

**Scoping and variable binding:**
- [`scope.rs`](https://github.com/rust-lang/rust/blob/5796073c134eaac30475f9a19462c4e716c9119c/tests/ui/rfcs/rfc-2294-if-let-guard/scope.rs) - Verifies that bindings created in `if let` guards are properly scoped and available in match arms
- [`shadowing.rs`](https://github.com/rust-lang/rust/blob/5796073c134eaac30475f9a19462c4e716c9119c/tests/ui/rfcs/rfc-2294-if-let-guard/shadowing.rs) - Tests that variable shadowing works correctly within guards
- [`scoping-consistency.rs`](https://github.com/rust-lang/rust/blob/5796073c134eaac30475f9a19462c4e716c9119c/tests/ui/rfcs/rfc-2294-if-let-guard/scoping-consistency.rs) - Ensures temporaries in guards remain valid for the duration of their match arms

**Type system integration:**
- [`type-inference.rs`](https://github.com/rust-lang/rust/blob/5796073c134eaac30475f9a19462c4e716c9119c/tests/ui/rfcs/rfc-2294-if-let-guard/type-inference.rs) - Confirms type inference works correctly in `if let` guards  
- [`typeck.rs`](https://github.com/rust-lang/rust/blob/5796073c134eaac30475f9a19462c4e716c9119c/tests/ui/rfcs/rfc-2294-if-let-guard/typeck.rs) - Verifies type mismatches are caught appropriately

**Pattern matching semantics:**
- [`exhaustive.rs`](https://github.com/rust-lang/rust/blob/5796073c134eaac30475f9a19462c4e716c9119c/tests/ui/rfcs/rfc-2294-if-let-guard/exhaustive.rs) - Validates that `if let` guards are correctly handled in exhaustiveness analysis
- [`move-guard-if-let.rs`](https://github.com/rust-lang/rust/blob/5796073c134eaac30475f9a19462c4e716c9119c/tests/ui/rfcs/rfc-2294-if-let-guard/move-guard-if-let.rs) and [`move-guard-if-let-chain.rs`](https://github.com/rust-lang/rust/blob/5796073c134eaac30475f9a19462c4e716c9119c/tests/ui/rfcs/rfc-2294-if-let-guard/move-guard-if-let-chain.rs) - Test that conditional moves in guards are tracked correctly by the borrow checker

### Error Handling and Diagnostics

- [`warns.rs`](https://github.com/rust-lang/rust/blob/5796073c134eaac30475f9a19462c4e716c9119c/tests/ui/rfcs/rfc-2294-if-let-guard/warns.rs) - Tests warnings for irrefutable patterns and unreachable code in guards
- [`parens.rs`](https://github.com/rust-lang/rust/blob/5796073c134eaac30475f9a19462c4e716c9119c/tests/ui/rfcs/rfc-2294-if-let-guard/parens.rs) - Ensures parentheses around `let` expressions are properly rejected
- [`macro-expanded.rs`](https://github.com/rust-lang/rust/blob/5796073c134eaac30475f9a19462c4e716c9119c/tests/ui/rfcs/rfc-2294-if-let-guard/macro-expanded.rs) - Verifies macro expansions that produce invalid constructs are caught
- [`guard-mutability-2.rs`](https://github.com/rust-lang/rust/blob/5796073c134eaac30475f9a19462c4e716c9119c/tests/ui/rfcs/rfc-2294-if-let-guard/guard-mutability-2.rs) - Tests mutability and ownership violations in guards
- [`ast-validate-guards.rs`](https://github.com/rust-lang/rust/blob/5796073c134eaac30475f9a19462c4e716c9119c/tests/ui/rfcs/rfc-2497-if-let-chains/ast-validate-guards.rs) - Validates AST-level syntax restrictions

### Drop Order and Temporaries

**Key insight:** Unlike `let_chains` in regular `if` expressions, `if let` guards do not have drop order inconsistencies because:
1. Match guards are clearly scoped to their arms
2. There is no "else block" equivalent that could cause temporal confusion

- [`drop-order.rs`](https://github.com/rust-lang/rust/blob/5796073c134eaac30475f9a19462c4e716c9119c/tests/ui/rfcs/rfc-2294-if-let-guard/drop-order.rs) - Check drop order of temporaries create in match guards
- [`compare-drop-order.rs`](https://github.com/rust-lang/rust/blob/aef3f5fdf052fbbc16e174aef5da6d50832ca316/tests/ui/rfcs/rfc-2294-if-let-guard/compare-drop-order.rs) - Compares drop order between `if let` guards and nested `if let` in match arms, confirming they behave identically across all editions
- rust-lang/rust#140981 - A complicated drop order test involved `let chain` was made by @est31
- [`drop-order-comparisons-let-chains.rs`](https://github.com/rust-lang/rust/blob/902b4d28783e03e231d8513082cc30c4fcce5d95/tests/ui/drop/drop-order-comparisons-let-chains.rs) - Compares drop order between `let chains` in `if let guard` and regular `if` expressions
- [`if-let-guards.rs`](https://github.com/rust-lang/rust/blob/5650d716e0589e2e145ce9027f35bd534e5f862a/tests/ui/drop/if-let-guards.rs) - Test correctness of drop order for bindings and temporaries
- [`if-let-guards-2`](https://github.com/rust-lang/rust/blob/3a6c8c8f3d7ae654fdb6ce1255182bda21680655/tests/ui/drop/if-let-guards-2.rs) - The same test as above but more comprehensive and tests more interactions between different features and their drop order, checking that drop order is correct, created by @traviscross 

## Edition Compatibility

This feature stabilizes on all editions, unlike `let chains` which was limited to edition 2024. This is safe because:

1. `if let` guards don't suffer from the drop order issues that affected `let chains` in regular `if` expressions
2. The scoping is unambiguous - guards are clearly tied to their match arms
3. Extensive testing confirms identical behavior across all editions

## Interactions with Future Features

The lang team has reviewed potential interactions with planned "guard patterns" and determined that stabilizing `if let` guards now does not create obstacles for future work. The scoping and evaluation semantics established here align with what guard patterns will need.

## Unresolved Issues

- [x] - rust-lang/rust#140981
- [x] - added tests description by @jieyouxu request
- [x] - Concers from @scottmcm about stabilizing this across all editions
- [x] - check if drop order in all edition when using `let chains` inside `if let` guard is the same
- [x] - interactions with guard patters
- [x] - pattern bindings drops before guard bindings https://github.com/rust-lang/rust/pull/143376
- [x] - documentaion (https://github.com/rust-lang/reference/pull/1957)
- [ ] (non-blocking) add tests for [this](https://github.com/rust-lang/rust/issues/145237) and [this](https://github.com/rust-lang/rust/pull/141295#issuecomment-3173059821)

---

**Related:**
- Tracking Issue: rust-lang/rust#51114  
- RFC: rust-lang/rfcs#2294
- Documentation PR: https://github.com/rust-lang/reference/pull/1957
2026-02-18 20:49:50 +00:00
Esteban Küber 37684bdfc5 Make all multipart suggestions verbose
The ShowAlways style of suggestions is usually easier to understand than the inline style.
2026-02-18 18:33:35 +00:00
Camille Gillot 6d4b1b38e7 Remove ShallowInitBox. 2026-02-17 11:25:50 +00:00
Kivooeo 964b63f42e if let guard stabilize 2026-02-16 12:24:15 +00:00
Jonathan Brouwer 018a5efcf7 Rename inline_fluent! to msg! 2026-02-14 13:47:52 +01:00
Jacob Pratt 4bcbf6274a Rollup merge of #152587 - lqd:tiny-things, r=jackh726
A couple of tiny polonius things

Here's a couple of tiny things I had ready to go @jackh726
- a tiny cleanup to avoid round-tripping through `Location`s to check for liveness, since we're already working with points
- while I was there, I fixed the doc which wasn't showing up properly (maybe a rustdoc or bootstrap bug when we build locally or during dist, either way, both don't show up correctly linked most of the time) for `PointIndex`es.
- and in the second commit slightly expand test coverage with [an example](https://internals.rust-lang.org/t/get-mut-map-back-from-entry-api/24003) that would have needed stdlib changes (cc author @Darksonn for visibility here)

More soon.

r? @jackh726
2026-02-13 22:26:36 -05:00
Rémy Rakic be204dd047 make per-point liveness accessible
It avoids round-tripping through `Location`s if you're working with
`Point`s already.
2026-02-13 17:10:29 +00:00
Jonathan Brouwer 98e8f99bc0 Rollup merge of #152218 - adwinwhite:fix-mir-borrowck-opaque-handling-keep-all-errors, r=lcnr
Report unconstrained region in hidden types lazily

Fixes https://github.com/rust-lang/trait-system-refactor-initiative/issues/264

I didn't copy the mechanism of HIR typeck as I found that we just need to be lax in the unconstrained region case.
It already ignores non-defining uses and invalid params.

About tests, I'm having trouble coming up with more complex ones. 🙁

This fixes `ukanren` and `codecrafters-redis-rust` but not rust-lang/rust#151322 and rust-lang/rust#151323.
I believe they are a [different problem](https://github.com/rust-lang/rust/issues/151322#issuecomment-3864656974).

r? @lcnr
2026-02-13 13:35:00 +01:00
Adwin White 20c46d647f report unconstrained region in hidden types lazily 2026-02-13 11:38:53 +08:00
Rémy Rakic 285e1be7b4 reduce duplication when finding a successor 2026-02-12 18:29:38 +00:00
Rémy Rakic 880d73396f merge remaining contexts
now that we need to hold the graph for MIR dumping, and the associated
data to traverse it, there is no difference between the main context and
diagnostics context, so we merge them.
2026-02-12 18:29:38 +00:00
Rémy Rakic 1b63325435 adapt polonius MIR dump to lazy graph traversal 2026-02-12 18:29:38 +00:00
Rémy Rakic 7de450ad52 introduce graph traversal abstraction and visitor
we may need to traverse the lazy graph multiple times:
- to record loan liveness
- to dump the localized outlives constraint in the polonius MIR dump

to do that we extract the previous loan liveness code into an abstract
traversal + visitor handling the liveness-specific parts, while the MIR
dump will be able to record constraints in its own visitor.
2026-02-12 18:29:38 +00:00
Rémy Rakic f4abd15bc5 remove unneeded liveness context
now that the analysis is only using the regular liveness shape, we don't
need to store it transposed, and thus don't need the container where it
was stored: the liveness context would be alone in the polonius context.

we thus remove the latter, and rename the former.
2026-02-12 18:29:38 +00:00
Rémy Rakic 5d151083fc optimization: do nothing if there are no loans 2026-02-12 18:29:38 +00:00
Rémy Rakic 6dcf65a1cb optimization: no need to convert liveness data shape anymore 2026-02-12 18:29:38 +00:00
Rémy Rakic 279d55c30a remove eager constraint conversion 2026-02-12 18:29:38 +00:00
Rémy Rakic 0941151f30 introduce lazy traversal for the polonius constraint graph 2026-02-12 18:29:37 +00:00
bors 7ad4e69ad5 Auto merge of #152517 - jhpratt:rollup-fGRcId6, r=jhpratt
Rollup of 17 pull requests

Successful merges:

 - rust-lang/rust#142415 (Add note when inherent impl for a alias type defined outside of the crate)
 - rust-lang/rust#142680 (Fix passing/returning structs with the 64-bit SPARC ABI)
 - rust-lang/rust#150768 (Don't compute FnAbi for LLVM intrinsics in backends)
 - rust-lang/rust#151152 (Add FCW for derive helper attributes that will conflict with built-in attributes)
 - rust-lang/rust#151814 (layout: handle rigid aliases without params)
 - rust-lang/rust#151863 (Borrowck: simplify diagnostics for placeholders)
 - rust-lang/rust#152159 (Add note for `?Sized` params in int-ptr casts diag)
 - rust-lang/rust#152434 (Clarify names of `QueryVTable` functions for "executing" a query)
 - rust-lang/rust#152478 (Remove tm_factory field from CodegenContext)
 - rust-lang/rust#152498 (Partially revert "resolve: Update `NameBindingData::vis` in place")
 - rust-lang/rust#152316 (fix: add continue)
 - rust-lang/rust#152394 (Correctly check if a macro call is actually a macro call in rustdoc highlighter)
 - rust-lang/rust#152425 (Port #![test_runner] to the attribute parser)
 - rust-lang/rust#152481 (Use cg_ssa's produce_final_output_artifacts in cg_clif)
 - rust-lang/rust#152485 (fix issue#152482)
 - rust-lang/rust#152495 (Clean up some subdiagnostics)
 - rust-lang/rust#152502 (Implement `BinaryHeap::from_raw_vec`)
2026-02-12 06:57:59 +00:00
Jacob Pratt 3ba1a835d1 Rollup merge of #152316 - cuiweixie:bugfix-continue, r=petrochenkov
fix: add continue

 should be same in:
https://github.com/rust-lang/rust/blob/d3ec6a351a027a71bdfbd36429288c1357ccdbea/compiler/rustc_trait_selection/src/error_reporting/infer/nice_region_error/static_impl_trait.rs#L156-L159
2026-02-12 00:41:09 -05:00
Jacob Pratt e4375da4e8 Rollup merge of #151863 - amandasystems:streamline-borrow-error-handling, r=lcnr
Borrowck: simplify diagnostics for placeholders

This folds the call to `region_from_element` into `RegionInferenceContext`, and simplifies the error variant for this case to only talk about regions as opposed to elements. This is the only case where a `RegionElement` leaks out of region inference, so now they can be considered internal to region inference (though that currently isn't expressed). It also clarifies the type information on the methods called to emphasise the fact that they only ever use placeholder regions in the diagnostics completely ignore any other element.

It also adds a bunch of FIXMEs to some fishy statements that conjure universes from what seems like arbitrary integers.

This was lifted from rust-lang/rust#142623.

r? @lcnr
2026-02-12 00:41:07 -05:00
Urgau 050b48a693 Rollup merge of #152281 - JohnTitor:sugg-mut-deref-borrows, r=estebank
borrowck: suggest `&mut *x` for pattern reborrows

Fixes rust-lang/rust#81059
r? @estebank as you should have some context here, but feel free to re-assign if you don't have time to review right now.
2026-02-12 00:04:14 +01:00
Lukas Bergdoll 2f3b952349 Stabilize assert_matches 2026-02-11 14:13:44 +01:00
Amanda Stjerna f53eed56d2 Borrowck: simplify diagnostics for placeholders.
This essentially folds the call to `region_from_element` into `RegionInferenceContext`,
and simplifies the error variant for this case. It also clarifies the type
information on the methods called to emphasise the fact that they only ever use
placeholder regions in the diagnostics, and completely ignore any other element.
2026-02-10 19:39:57 +01:00
Matthias Krüger 1f0e21584e Rollup merge of #152327 - adwinwhite:fix-non-defining-use-ices-ready, r=lcnr
Check stalled coroutine obligations eagerly

Fixes rust-lang/rust#151322
Fixes rust-lang/rust#151323
Fixes rust-lang/rust#137916
Fixes rust-lang/rust#138274

The problem is that stalled coroutine obligations can't be satisifed so that they cause normalization to fail in `mir_borrowck`.
Thus, we failed to register any opaque to storage in the next solver.
I fix it by checking these obligations earlier in `mir_borrowck`.

r? @lcnr
2026-02-09 18:39:43 +01:00
Matthias Krüger 7ecefd01d5 Rollup merge of #152315 - cuiweixie:bugfix-span, r=jieyouxu
fix: rhs_span to rhs_span_new
2026-02-09 18:39:43 +01:00
Weixie Cui 40a264cd45 fix: rhs_span to rhs_span_new 2026-02-09 22:16:36 +08:00
Adwin White d8ff397cd6 check stalled coroutine obligations eagerly 2026-02-08 23:57:50 +08:00
Stuart Cook 8e16ea8749 Rollup merge of #152037 - eggyal:unused-mut-due-to-borrowck-error, r=jackh726
Suppress unused_mut lint if mutation fails due to borrowck error

Remedying the borrowck error will likely result in the mut becoming used, and therefore the lint is likely incorrect.

Fixes rust-lang/rust#152024
r? compiler
2026-02-08 16:58:24 +11:00
Stuart Cook 68f4a99963 Rollup merge of #151887 - scottmcm:homogeneous-try-in-compiler, r=jackh726
Remove some unnecessary `try`-related type annotations

I left a few, like
```rust
let result: Result<_, ModError<'_>> = try {
```
where it felt like seeing it might still be useful for the reader.

Feel free to push back on any of these changes if you think they should be left alone.
2026-02-08 16:58:23 +11:00
Weixie Cui d3ec6a351a fix: add continue 2026-02-08 11:40:56 +08:00
Jana Dönszelmann cf1a784f3f Port rustc_regions to the new attribute parser 2026-02-07 17:24:40 +01:00
Yuki Okushi 0de7415875 borrowck: suggest &mut *x for pattern reborrows 2026-02-07 20:29:15 +09:00
Jonathan Brouwer 65a1d9708d Rollup merge of #152107 - JonathanBrouwer:convert_borrowck, r=lqd
Convert to inline diagnostics in `rustc_borrowck`

For https://github.com/rust-lang/rust/issues/151366
r? @jdonszelmann
2026-02-06 10:06:43 +01:00
许杰友 Jieyou Xu (Joe) 7b821d1752 Rollup merge of #151278 - estebank:issue-108894, r=davidtwco
Provide more context on trait bounds being unmet due to imperfect derive

When encountering a value that has a borrow checker error where the type was previously moved, when suggesting cloning verify that it is not already being derived. If it is, explain why the `derive(Clone)` doesn't apply:

```
note: if `TypedAddress<T>` implemented `Clone`, you could clone the value
  --> $DIR/derive-clone-implicit-bound.rs:6:1
   |
LL | #[derive(Clone, Copy)]
   |          ----- derived `Clone` adds implicit bounds on type parameters
LL | pub struct TypedAddress<T>{
   | ^^^^^^^^^^^^^^^^^^^^^^^^-^
   | |                       |
   | |                       introduces an implicit `T: Clone` bound
   | consider manually implementing `Clone` for this type
...
LL |         let old = self.return_value(offset);
   |                                     ------ you could clone this value
```

When encountering a bound coming from a derive macro, suggest manual impl of the trait.

Use the span for the specific param when adding bounds in builtin derive macros, so the diagnostic will point at them as well as the derive macro itself.

```
note: required for `Id<SomeNode>` to implement `PartialEq`
  --> $DIR/derive-implicit-bound.rs:5:10
   |
LL | #[derive(PartialEq, Eq)]
   |          ^^^^^^^^^
LL | pub struct Id<T>(PhantomData<T>);
   |               - unsatisfied trait bound introduced in this `derive` macro
   = help: consider manually implementing `PartialEq` to avoid undesired bounds
```

Mention that the trait could be manually implemented in E0599.

Fix rust-lang/rust#108894. Address rust-lang/rust#143714. Address #rust-lang/rust#146515 (but ideally would also suggest constraining the fn bound correctly as well).
2026-02-06 10:25:43 +08:00
Jonathan Brouwer dd61998e74 Convert to inline diagnostics in rustc_borrowck 2026-02-05 16:55:55 +01:00
Alan Egerton 5405e5d06e Suppress unused_mut lint if mutation fails due to borrowck error
Remedying the borrowck error will likely result in the mut becoming
used.
2026-02-03 11:52:00 +00:00
Jonathan Brouwer 5144366f4a Rollup merge of #151172 - estebank:default-field-values, r=dianne
Use default field values in a few more cases

Makes the use expressions significantly shorter.
2026-02-02 18:52:13 +01:00
Esteban Küber dffec20dee Tweak help to unify formatting and wording 2026-02-01 18:20:31 +00:00
Esteban Küber 879633f97b Change note to help 2026-02-01 18:20:31 +00:00