Introduce `enter_forall` to supercede `instantiate_binder_with_placeholders`
r? `@lcnr`
Long term we'd like to experiment with decrementing the universe count after "exiting" binders so that we do not end up creating infer vars in non-root universes even when they logically reside in the root universe. The fact that we dont do this currently results in a number of issues in the new trait solver where we consider goals to be ambiguous because otherwise it would require lowering the universe of an infer var. i.e. the goal `?x.0 eq <T as Trait<?y.1>>::Assoc` where the alias is rigid would not be able to instantiate `?x` with the alias as there would be a universe error.
This PR is the first-ish sort of step towards being able to implement this as eventually we would want to decrement the universe in `enter_forall`. Unfortunately its Difficult to actually implement decrementing universes nicely so this is a separate step which moves us closer to the long term goal ✨
Rollup of 9 pull requests
Successful merges:
- #119592 (resolve: Unload speculatively resolved crates before freezing cstore)
- #120103 (Make it so that async-fn-in-trait is compatible with a concrete future in implementation)
- #120206 (hir: Make sure all `HirId`s have corresponding HIR `Node`s)
- #120214 (match lowering: consistently lower bindings deepest-first)
- #120688 (GVN: also turn moves into copies with projections)
- #120702 (docs: also check the inline stmt during redundant link check)
- #120727 (exhaustiveness: Prefer "`0..MAX` not covered" to "`_` not covered")
- #120734 (Add `SubdiagnosticMessageOp` as a trait alias.)
- #120739 (improve pretty printing for associated items in trait objects)
r? `@ghost`
`@rustbot` modify labels: rollup
improve pretty printing for associated items in trait objects
* Don't print a binder in front of associated items, because it's not valid syntax.
* e.g. print `dyn for<'a> Trait<'a, Assoc = &'a u8>` instead of `dyn for<'a> Trait<'a, for<'a> Assoc = &'a u8>`.
* Don't print associated items that are implied by a supertrait bound.
* e.g. if we have `trait Sub: Super<Assoc = u8> {}`, then just print `dyn Sub` instead of `dyn Sub<Assoc = u8>`.
I've added the test in the first commit, so you can see the diff of the compiler output in the second commit.
exhaustiveness: Prefer "`0..MAX` not covered" to "`_` not covered"
There was an exception when reporting integer ranges as missing, it's been there for as long as I can remember. This PR removes it. I think it's nicer to report "`0..MAX` not covered" than "`_` not covered". This also makes it consistent with enums, where we report individual enum variants in this case (as showcased in the rest of the `empty-match.rs` test).
r? ``@estebank``
match lowering: consistently lower bindings deepest-first
Currently when lowering match expressions to MIR, we do a funny little dance with the order of bindings. I attempt to explain it in the third commit: we handle refutable (i.e. needing a test) patterns differently than irrefutable ones. This leads to inconsistencies, as reported in https://github.com/rust-lang/rust/issues/120210. The reason we need a dance at all is for situations like:
```rust
fn foo1(x: NonCopyStruct) {
let y @ NonCopyStruct { copy_field: z } = x;
// the above should turn into
let z = x.copy_field;
let y = x;
}
```
Here the `y ```````@```````` binding will move out of `x`, so we need to copy the field first.
I believe that the inconsistency came about when we fixed https://github.com/rust-lang/rust/issues/69971, and didn't notice that the fix didn't extend to refutable patterns. My guess then is that ordering bindings by "deepest-first, otherwise source order" is a sound choice. This PR implements that (at least I hope, match lowering is hard to follow 🥲).
Fixes https://github.com/rust-lang/rust/issues/120210
r? ```````@oli-obk``````` since you merged the original fix to https://github.com/rust-lang/rust/issues/69971
cc ```````@matthewjasper```````
Make it so that async-fn-in-trait is compatible with a concrete future in implementation
There's no technical reason why an AFIT like `async fn foo()` cannot be satisfied with an implementation signature like `fn foo() -> Pin<Box<dyn Future<Output = ()> + 'static>>`.
We rejected this previously because we were uncertain about how AFITs worked with refinement, but I don't believe this needs to be a restriction any longer.
r? oli-obk
resolve: Unload speculatively resolved crates before freezing cstore
Name resolution sometimes loads additional crates to improve diagnostics (e.g. suggest imports).
Not all of these diagnostics result in errors, sometimes they are just warnings, like in #117772.
If additional crates loaded speculatively stay and gets listed by things like `query crates` then they may produce further errors like duplicated lang items, because lang items from speculatively loaded crates are as good as from non-speculatively loaded crates.
They can probably do things like adding unintended impls from speculatively loaded crates to method resolution as well.
The extra crates will also get into the crate's metadata as legitimate dependencies.
In this PR I remove the speculative crates from cstore when name resolution is finished and cstore is frozen.
This is better than e.g. filtering away speculative crates in `query crates` because things like `DefId`s referring to these crates and leaking to later compilation stages can produce ICEs much easier, allowing to detect them.
The unloading could potentially be skipped if any errors were reported (to allow using `DefId`s from speculatively loaded crates for recovery), but I didn't do it in this PR because I haven't seen such cases of recovery. We can reconsider later if any relevant ICEs are reported.
Unblocks https://github.com/rust-lang/rust/pull/117772.
Stop bailing out from compilation just because there were incoherent traits
fixes#120343
but also has a lot of "type annotations needed" fallout. Some are fixed in the second commit.
Reconstify `Add`
r? project-const-traits
I'm not happy with the ui test changes (or failures because I did not bless them and include the diffs in this PR). There is at least some bugs I need to look and try fix:
1. A third duplicated diagnostic when a consumer crate that does not have `effects` enabled has a trait selection error for an upstream const_trait trait. See tests/ui/ufcs/ufcs-qpath-self-mismatch.rs.
2. For some reason, making `Add` a const trait would stop us from suggesting `T: Add` when we try to add two `T`s without that bound. See tests/ui/suggestions/issue-97677.rs
```
error: equality constraints are not yet supported in `where` clauses
--> $DIR/equality-bound.rs:50:9
|
LL | IntoIterator::Item = A,
| ^^^^^^^^^^^^^^^^^^^^^^ not supported
|
= note: see issue #20041 <https://github.com/rust-lang/rust/issues/20041> for more information
help: if `IntoIterator::Item` is an associated type you're trying to set, use the associated type binding syntax
|
LL ~ fn from_iter<T: IntoIterator<Item = A>>(_: T) -> Self
LL | where
LL ~
|
error: equality constraints are not yet supported in `where` clauses
--> $DIR/equality-bound.rs:63:9
|
LL | T::Item = A,
| ^^^^^^^^^^^ not supported
|
= note: see issue #20041 <https://github.com/rust-lang/rust/issues/20041> for more information
help: if `IntoIterator::Item` is an associated type you're trying to set, use the associated type binding syntax
|
LL ~ fn from_iter<T: IntoIterator<Item = A>>(_: T) -> Self
LL | where
LL ~
|
```
Fix#68982.
Record coroutine kind in coroutine generics
Oops, added a new substitution (the "kind" ty) to coroutines but forgot to record it in the `generics_of`. I'm surprised I left this out of the coroutine-closure PR -- I thought I made this change; I possibly rebased it out by accident.
Fixes#120732
r? oli-obk
Remove some `unchecked_claim_error_was_emitted` calls
We want to drive the number of these calls down as much as possible. This PR gets rid of a bunch of them.
r? ``@oli-obk``
MirPass: make name more const
Continues #120161, this time applied to `MirPass` instead of `MirLint`, locally shaves few (very few) instructions off.
r? ``@cjgillot``
pattern_analysis: gather up place-relevant info
We track 3 things about each place during exhaustiveness: its type, its (data) validity, and whether it's the scrutinee place. This PR gathers all three into a single struct.
r? `````@compiler-errors`````
coverage: Split out counter increment sites from BCB node/edge counters
This makes it possible for two nodes/edges in the coverage graph to share the same counter, without causing the instrumentor to inject unwanted duplicate counter-increment statements.
---
````@rustbot```` label +A-code-coverage
Suggest turning `if let` into irrefutable `let` if appropriate
When encountering an `if let` tail expression without an `else` arm for an enum with a single variant, suggest writing an irrefutable `let` binding instead.
```
error[E0317]: `if` may be missing an `else` clause
--> $DIR/irrefutable-if-let-without-else.rs:8:5
|
LL | fn foo(x: Enum) -> i32 {
| --- expected `i32` because of this return type
LL | / if let Enum::Variant(value) = x {
LL | | value
LL | | }
| |_____^ expected `i32`, found `()`
|
= note: `if` expressions without `else` evaluate to `()`
= help: consider adding an `else` block that evaluates to the expected type
help: consider using an irrefutable `let` binding instead
|
LL ~ let Enum::Variant(value) = x;
LL ~ value
|
```
Fix#61788.
Mark "unused binding" suggestion as maybe incorrect
Ignoring unused bindings should be a determination made by a human, `rustfix` shouldn't auto-apply the suggested change.
Fix#54196.
various const interning cleanups
After #119044 I noticed that some things can be simplified and refactored.
This is also a requirement for https://github.com/rust-lang/rust/pull/116564 as there we'll need to treat the base allocation differently from the others
r? ````@RalfJung````
- In `emit_producing_error_guaranteed`, only allow `Level::Error`.
- In `emit_diagnostic`, only produce `ErrorGuaranteed` for `Level` and
`DelayedBug`. (Not `Bug` or `Fatal`. They don't need it, because the
relevant `emit` methods abort.)
- Add/update various comments.
When `catch_fatal_errors` catches a `FatalErrorMarker`, it returns an
`ErrorGuaranteed` that is conjured out of thin air with
`unchecked_claim_error_was_emitted`. But that `ErrorGuaranteed` is never
used.
This commit changes it to instead conjure a `FatalError` out of thin
air. (A non-deprecated action!) This makes more sense because
`FatalError` and `FatalErrorMarker` are a natural pairing -- a
`FatalErrorMarker` is created by calling `FatalError::raise`, so this is
effectively getting back the original `FatalError`.
This requires a tiny change in `catch_with_exit_code`. The old result of
the `catch_fatal_errors` call there was
`Result<Result<(), ErrorGuaranteed>, ErrorGuaranteed>` which could be
`flatten`ed into `Result<(), ErrorGuaranteed>`. The new result of the
`catch_fatal_errors` calls is
`Result<Result<(), ErrorGuaranteed>, FatalError>`, which can't be
`flatten`ed but is still easily matched for the success case.
Don't expect early-bound region to be local when reporting errors in RPITIT well-formedness
The implicit lifetime in the example code gets replaced with `ReError`, which fails a `sub_regions` check in the lexical region solver. Error reporting ends up calling `is_suitable_region` on an early bound region in the *trait* definition. This causes an ICE because we `expect_local()`.
This is kind of a bad explanation, but this code just makes diagnostics reporting a bit more gracefully fallible. If the reviewer wants a thorough investigation of exactly where we get this region outlives obligation, I can write one up. Doesn't really seem worth it, though, imo.
Fixes#120638Fixes#120648
Normalize type outlives obligations in NLL for new solver
Normalize the type outlives assumptions and obligations in MIR borrowck. This should fix any of the lazy-norm-related MIR borrowck problems.
Also some cleanups from last PR:
1. Normalize obligations in a loop in lexical region resolution
2. Use `deeply_normalize_with_skipped_universes` in lexical resolution since we may have, e.g. `for<'a> Alias<'a>: 'b`.
r? lcnr
Account for non-overlapping unmet trait bounds in suggestion
When a method not found on a type parameter could have been provided by any
of multiple traits, suggest each trait individually, instead of a single
suggestion to restrict the type parameter with *all* of them.
Before:
```
error[E0599]: the method `cmp` exists for reference `&T`, but its trait bounds were not satisfied
--> $DIR/method-on-unbounded-type-param.rs:5:10
|
LL | (&a).cmp(&b)
| ^^^ method cannot be called on `&T` due to unsatisfied trait bounds
|
= note: the following trait bounds were not satisfied:
`T: Ord`
which is required by `&T: Ord`
`&T: Iterator`
which is required by `&mut &T: Iterator`
`T: Iterator`
which is required by `&mut T: Iterator`
help: consider restricting the type parameters to satisfy the trait bounds
|
LL | fn g<T>(a: T, b: T) -> std::cmp::Ordering where T: Iterator, T: Ord {
| +++++++++++++++++++++++++
```
After:
```
error[E0599]: the method `cmp` exists for reference `&T`, but its trait bounds were not satisfied
--> $DIR/method-on-unbounded-type-param.rs:5:10
|
LL | (&a).cmp(&b)
| ^^^ method cannot be called on `&T` due to unsatisfied trait bounds
|
= note: the following trait bounds were not satisfied:
`T: Ord`
which is required by `&T: Ord`
`&T: Iterator`
which is required by `&mut &T: Iterator`
`T: Iterator`
which is required by `&mut T: Iterator`
= help: items from traits can only be used if the type parameter is bounded by the trait
help: the following traits define an item `cmp`, perhaps you need to restrict type parameter `T` with one of them:
|
LL | fn g<T: Ord>(a: T, b: T) -> std::cmp::Ordering {
| +++++
LL | fn g<T: Iterator>(a: T, b: T) -> std::cmp::Ordering {
| ++++++++++
```
Fix#108428.
Follow up to #120396, only last commit is relevant.
update indirect structural match lints to match RFC and to show up for dependencies
This is a large step towards implementing https://github.com/rust-lang/rfcs/pull/3535.
We currently have five lints related to "the structural match situation":
- nontrivial_structural_match
- indirect_structural_match
- pointer_structural_match
- const_patterns_without_partial_eq
- illegal_floating_point_literal_pattern
This PR concerns the first 3 of them. (The 4th already is set up to show for dependencies, and the 5th is removed by https://github.com/rust-lang/rust/pull/116284.) nontrivial_structural_match is being removed as per the RFC; the other two are enabled to show up in dependencies.
Fixes https://github.com/rust-lang/rust/issues/73448 by removing the affected analysis.
Account for unbounded type param receiver in suggestions
When encountering
```rust
fn f<T>(a: T, b: T) -> std::cmp::Ordering {
a.cmp(&b) //~ ERROR E0599
}
```
output
```
error[E0599]: no method named `cmp` found for type parameter `T` in the current scope
--> $DIR/method-on-unbounded-type-param.rs:2:7
|
LL | fn f<T>(a: T, b: T) -> std::cmp::Ordering {
| - method `cmp` not found for this type parameter
LL | a.cmp(&b)
| ^^^ method cannot be called on `T` due to unsatisfied trait bounds
|
= help: items from traits can only be used if the type parameter is bounded by the trait
help: the following traits define an item `cmp`, perhaps you need to restrict type parameter `T` with one of them:
|
LL | fn f<T: Ord>(a: T, b: T) -> std::cmp::Ordering {
| +++++
LL | fn f<T: Iterator>(a: T, b: T) -> std::cmp::Ordering {
| ++++++++++
```
Fix#120186.
pattern_analysis: use a plain `Vec` in `DeconstructedPat`
The use of an arena-allocated slice in `DeconstructedPat` dates to when we needed the arena anyway for lifetime reasons. Now that we don't, I'm thinking that if `thir::Pat` can use plain old `Vec`s, maybe so can I.
r? ```@ghost```
hir: Stop keeping prefixes for most of `use` list stems
And make sure all other imports have non-empty resolution lists.
Addresses one of FIXMEs in https://github.com/rust-lang/rust/pull/120206.
rustc_monomorphize: fix outdated comment in partition
`max_cgu_count` was removed in 51821515b3, but not comment (usage in `merge_codegen_units` was removed earlier).
r? `@nnethercote`
Suggest `[tail @ ..]` on `[..tail]` and `[...tail]` where `tail` is unresolved
Fixes#120591.
~~Will conflict with #120570~~ (rebased).
r? estebank or compiler
Some cleanups around diagnostic levels.
Plus some refactoring in and around diagnostic levels and emission. Details in the individual commit logs.
r? ````@oli-obk````
Rework support for async closures; allow them to return futures that borrow from the closure's captures
This PR implements a new lowering for async closures via `TyKind::CoroutineClosure` which handles the curious relationship between the closure and the coroutine that it returns.
I wrote up a bunch in [this hackmd](https://hackmd.io/`@compiler-errors/S1HvqQxca)` which will be copied to the dev guide after this PR lands, and hopefully left sufficient comments in the source code explaining why this change is as large as it is.
This also necessitates that they begin implementing the `AsyncFn`-family of traits, rather than the `Fn`-family of traits -- if you need `Fn` implementations, you should probably use the non-sugar `|| async {}` syntax instead.
Notably this PR does not yet implement `async Fn()` syntax sugar for bounds, but I expect to add those soon (**edit:** #120392). For now, users must use `AsyncFn()` traits directly, which necessitates adding the `async_fn_traits` feature gate as well. I will add this as a follow-up very soon.
r? oli-obk
This is based on top of #120322, but that PR is minimal.
This rewrite makes the cache-updating nature of the function slightly clearer, using the Entry API into the hash table for region names to capture the update-insert nature of the method. May be marginally more efficient since it only runtime-borrows the map once, but in this context the performance impact is almost certainly completely negligible.
When encountering an `if let` tail expression without an `else` arm for an
enum with a single variant, suggest writing an irrefutable `let` binding
instead.
```
error[E0317]: `if` may be missing an `else` clause
--> $DIR/irrefutable-if-let-without-else.rs:8:5
|
LL | fn foo(x: Enum) -> i32 {
| --- expected `i32` because of this return type
LL | / if let Enum::Variant(value) = x {
LL | | value
LL | | }
| |_____^ expected `i32`, found `()`
|
= note: `if` expressions without `else` evaluate to `()`
= help: consider adding an `else` block that evaluates to the expected type
help: consider using an irrefutable `let` binding instead
|
LL ~ let Enum::Variant(value) = x;
LL ~ value
|
```
Fix#61788.
That is, change `diagnostic_outside_of_impl` and
`untranslatable_diagnostic` from `allow` to `deny`, because more than
half of the compiler has be converted to use translated diagnostics.
This commit removes more `deny` attributes than it adds `allow`
attributes, which proves that this change is warranted.
Introduce support for `async` bound modifier on `Fn*` traits
Adds `async` to the list of `TraitBoundModifiers`, which instructs AST lowering to map the trait to an async flavor of the trait. For now, this is only supported for `Fn*` to `AsyncFn*`, and I expect that this manual mapping via lang items will be replaced with a better system in the future.
The motivation for adding these bounds is to separate the users of async closures from the exact trait desugaring of their callable bounds. Instead of users needing to be concerned with the `AsyncFn` trait, they should be able to write `async Fn()` and it will desugar to whatever underlying trait we decide is best for the lowering of async closures.
Note: rustfmt support can be done in the rustfmt repo after a subtree sync.
pattern_analysis: Gracefully abort on type incompatibility
This leaves the option for a consumer of the crate to return `Err` instead of panicking on type error. rust-analyzer could use that (e.g. https://github.com/rust-lang/rust-analyzer/issues/15808).
Since the only use of `TypeCx::bug` is in `Constructor::is_covered_by`, it is tempting to return `false` instead of `Err()`, but that would cause "non-exhaustive match" false positives.
r? `@compiler-errors`
All the other `emit`/`emit_diagnostic` methods were recently made
consuming (e.g. #119606), but this one wasn't. But it makes sense to.
Much of this is straightforward, and lots of `clone` calls are avoided.
There are a couple of tricky bits.
- `Emitter::primary_span_formatted` no longer takes a `Diagnostic` and
returns a pair. Instead it takes the two fields from `Diagnostic` that
it used (`span` and `suggestions`) as `&mut`, and modifies them. This
is necessary to avoid the cloning of `diag.children` in two emitters.
- `from_errors_diagnostic` is rearranged so various uses of `diag` occur
before the consuming `emit_diagnostic` call.
target: default to the medium code model on LoongArch targets
The Rust LoongArch targets have been using the default LLVM code model so far, which is "small" in LLVM-speak and "normal" in LoongArch-speak. As [described][1] in the "Code Model" section of LoongArch ELF psABI spec v20231219, one can only make function calls as far as ±128MiB with the "normal" code model; this is insufficient for very large software containing Rust components that needs to be linked into the big text section, such as Chromium.
Because:
* we do not want to ask users to recompile std if they are to build such software,
* objects compiled with larger code models can be linked with those with smaller code models without problems, and
* the "medium" code model is comparable to the "small"/"normal" one performance-wise (same data access pattern; each function call becomes 2-insn long and indirect, but this may be relaxed back into the direct 1-insn form in a future LLVM version), but is able to perform function calls within ±128GiB,
it is better to just switch the targets to the "medium" code model, which is also "medium" in LLVM-speak.
[1]: https://github.com/loongson/la-abi-specs/blob/v2.30/laelf.adoc#code-models
riscv only supports split_debuginfo=off for now
Disable packed/unpacked options for riscv linux/android. Other riscv targets already only have the off option.
The packed/unpacked options might be supported in the future. See upstream issue for more details:
https://github.com/llvm/llvm-project/issues/56642Fixes#110224
make matching on NaN a hard error, and remove the rest of illegal_floating_point_literal_pattern
These arms would never be hit anyway, so the pattern makes little sense. We have had a future-compat lint against float matches in general for a *long* time, so I hope we can get away with immediately making this a hard error.
This is part of implementing https://github.com/rust-lang/rfcs/pull/3535.
Closes https://github.com/rust-lang/rust/issues/41620 by removing the lint.
https://github.com/rust-lang/reference/pull/1456 updates the reference to match.
The Rust LoongArch targets have been using the default LLVM code model
so far, which is "small" in LLVM-speak and "normal" in LoongArch-speak.
As described in the "Code Model" section of LoongArch ELF psABI spec
v20231219 [1], one can only make function calls as far as ±128MiB with
the "normal" code model; this is insufficient for very large software
containing Rust components that needs to be linked into the big text
section, such as Chromium.
Because:
* we do not want to ask users to recompile std if they are to build
such software,
* objects compiled with larger code models can be linked with those
with smaller code models without problems, and
* the "medium" code model is comparable to the "small"/"normal" one
performance-wise (same data access pattern; each function call
becomes 2-insn long and indirect, but this may be relaxed back into
the direct 1-insn form in a future LLVM version), but is able to
perform function calls within ±128GiB,
it is better to just switch the targets to the "medium" code model,
which is also "medium" in LLVM-speak.
[1]: https://github.com/loongson/la-abi-specs/blob/v2.30/laelf.adoc#code-models
coverage: Improve handling of function/closure spans
This is a combination of some loosely-related changes that touch the same code:
1. Make unexpansion of closure bodies more precise, by unexpanding back to the context of the closure declaration, instead of unexpanding all the way back to the top-level context. This preserves the way we handle async desugaring and closures containing a single bang-macro, while also giving better results for closures defined in macros.
2. Skip the normal span-refinement code when dealing with the trivial outer part of an async function.
3. Be more explicit about the fact that `fn_sig_span` has been extended to the start of the function body, and is not necessarily present.
---
`@rustbot` label +A-code-coverage
Move predicate, region, and const stuff into their own modules in middle
This PR mostly moves things around, and in a few cases adds some `ty::` to the beginning of names to avoid one-off imports.
I don't mean this to be the most *thorough* move/refactor. I just generally wanted to begin to split up `ty/mod.rs` and `ty/sty.rs` which are huge and hard to distinguish, and have a lot of non-ty stuff in them.
r? lcnr
This sidesteps the normal span refinement code in cases where we know that we
are only dealing with the special signature span that represents having called
an async function.
The two kinds of delayed bug have quite different semantics so a
stronger conceptual separation is nice. (`is_error` is a good example,
because the two kinds have different behaviour.)
The commit also moves the `DelayedBug` variant after `Error` in `Level`,
to reflect the fact that it's weaker than `Error` -- it might trigger an
error but also might not. (The pre-existing `downgrade_to_delayed_bug`
function also reflects the notion that delayed bugs are lower/after
normal errors.)
Plus it condenses some of the comments on `Level` into a table, for
easier reading, and introduces `can_be_top_or_sub` to indicate which
levels can be used in top-level diagnostics vs. subdiagnostics.
Finally, it renames `DiagCtxtInner::span_delayed_bugs` as
`DiagCtxtInner::delayed_bugs`. The `span_` prefix is unnecessary because
some delayed bugs don't have a span.
- Combine two different blocks involving
`diagnostic.level.get_expectation_id()` into one.
- Combine several `if`s involving `diagnostic.level` into a single
`match`.
This requires reordering some of the operations, but this has no
functional effect.
Rollup of 8 pull requests
Successful merges:
- #119759 (Add FileCheck annotations to dataflow-const-prop tests)
- #120323 (On E0277 be clearer about implicit `Sized` bounds on type params and assoc types)
- #120473 (Only suggest removal of `as_*` and `to_` conversion methods on E0308)
- #120540 (add test for try-block-in-match-arm)
- #120547 (`#![feature(inline_const_pat)]` is no longer incomplete)
- #120552 (Correctly check `never_type` feature gating)
- #120555 (put pnkfelix (me) back on the review queue.)
- #120556 (Improve the diagnostics for unused generic parameters)
r? `@ghost`
`@rustbot` modify labels: rollup
It doesn't affect behaviour, but makes sense with (a) `FailureNote` having
`()` as its emission guarantee, and (b) in `Level` the `is_error` levels
now are all listed before the non-`is_error` levels.
Rollup of 8 pull requests
Successful merges:
- #120484 (Avoid ICE when is_val_statically_known is not of a supported type)
- #120516 (pattern_analysis: cleanup manual impls)
- #120517 (never patterns: It is correct to lower `!` to `_`.)
- #120523 (Improve `io::Read::read_buf_exact` error case)
- #120528 (Store SHOULD_CAPTURE as AtomicU8)
- #120529 (Update data layouts in custom target tests for LLVM 18)
- #120531 (Remove a bunch of `has_errors` checks that have no meaningful or the wrong effect)
- #120533 (Correct paths for hexagon-unknown-none-elf platform doc)
r? `@ghost`
`@rustbot` modify labels: rollup
Improve the diagnostics for unused generic parameters
* Don't emit two errors (namely E0091 *and* E0392) for unused type parameters on *lazy* type aliases
* Fix the diagnostic help message of E0392 for *lazy* type aliases: Don't talk about the “fields” of lazy type aliases (use the term “body” instead) and don't suggest `PhantomData` for them, it doesn't make much sense
* Consolidate the diagnostics for E0091 (unused type parameters in type aliases) and E0392 (unused generic parameters due to bivariance) and make it translatable
* Still keep the error codes distinct (for now)
* Naturally leads to better diagnostics for E0091
r? ```@oli-obk``` (to ballast your review load :P) or compiler
Correctly check `never_type` feature gating
Fixes#120542.
The feature wasn't tested on return type of a generic function type, so it got under the radar in https://github.com/rust-lang/rust/pull/120316.
r? ```@compiler-errors```
`#![feature(inline_const_pat)]` is no longer incomplete
Now that borrow checking and safety checking is implemented for inline constant patterns, the incomplete feature status is not necessary. Stabilizing this feature requires more testing and has some of the same unresolved questions as inline constants.
cc #76001
it works when a non-const context that does not enable effects
calls into a const effects-enabled trait. We'd simply suggest the
non-const trait bound in this case consistent to its fallback.
never patterns: It is correct to lower `!` to `_`.
This is just a comment update but a non-trivial one: it is correct to lower `!` patterns as `_`. The reasoning is that `!` matches all the possible values of the type, since the type is empty. Moreover, we do want to warn that the `Err` is redundant in:
```rust
match x {
!,
Err(!),
}
```
which is consistent with `!` behaving like a wildcard.
I did try to introduce `Constructor::Never` and it ended up needing to behave exactly like `Constructor::Wildcard`.
r? ```@compiler-errors```
Avoid ICE when is_val_statically_known is not of a supported type
2 ICE with 1 stone!
1. Implement `llvm.is.constant.ptr` to avoid first ICE in linked issue.
2. return `false` when the argument is not one of `i*`/`f*`/`ptr` to avoid second ICE.
fixes#120480
hir: Remove the generic type parameter from `MaybeOwned`
It's only ever used with a reference to `OwnerInfo` as an argument.
Follow up to https://github.com/rust-lang/rust/pull/120346.
Remove `BorrowckErrors::tainted_by_errors`
This PR removes one of the `tainted_by_errors` occurrences, replacing it with direct use of `ErrorGuaranteed`.
r? `@oli-obk`
Suggest changing type to const parameters if we encounter a type in the trait bound position
The first commit is just drive-by cleanup.
Provide a structured suggestion if the user forgot to prefix a “const parameter” with `const`, e.g., in `struct Tagged<TAG: u64>;`. This happens to me from time to time. Maybe C++ devs are also prone to this mistake given template syntax looks like `template<typename T, uint32_t N>`.
`emit_future_breakage` calls
`self.dcx().take_future_breakage_diagnostics()` and then passes the
result to `self.dcx().emit_future_breakage_report(diags)`. This commit
removes the first of these and lets `emit_future_breakage_report` do the
taking.
It also inlines and removes what is left of `emit_future_breakage`,
which has a single call site.
- `emitted_at` isn't used outside the crate.
- `code` and `messages` are public fields, so there's no point have
trivial getters/setters for them.
- `suggestions` is public, so the comment about "functionality on
`Diagnostic`" isn't needed.
`BorrowckErrors` stores a mix of error and non-error diags in
`buffered`. As a result, it downgrades `DiagnosticBuilder`s to
`Diagnostic`s, losing the emission guarantees, and so has to use a
`tainted_by_errors` field to record whether an error has occurred.
This commit splits `buffered` into `buffered_errors` and
`buffered_non_errors`, keeping them as `DiagnosticBuilder`s and
preserving the emission guarantees.
This also requires fixing a bunch of incorrect lifetimes on
`DiagnosticBuilder` use points.
* Get rid of a typo in a function name
* Rename `currently_processing_generics`: The old name confused me at first since
I assumed it referred to generic *parameters* when it was in fact referring to
generic *arguments*. Generics are typically short for generic params.
* Get rid of a few unwraps by properly leveraging slice patterns
This makes it possible for two nodes/edges in the coverage graph to share the
same counter, without causing the instrumentor to inject unwanted duplicate
counter-increment statements.
When there are two possibilities, both of which use a `String`, it's
nicer to use a struct than an enum. Especially when mapping the contents
into a tuple.
It contains an `i128`, but when creating them we convert any number
outside the range -100..100 to a string, because Fluent uses an `f64`.
It's all a bit strange.
This commit changes the `i128` to an `i32`, which fits safely in
Fluent's `f64`, and removes the -100..100 range check. This means that
only integers outside the range of `i32` will be converted to strings.
```
error[E0277]: the size for values of type `[i32]` cannot be known at compilation time
--> f100.rs:2:33
|
2 | let _ = std::mem::size_of::<[i32]>();
| ^^^^^ doesn't have a size known at compile-time
|
= help: the trait `Sized` is not implemented for `[i32]`
note: required by an implicit `Sized` bound in `std::mem::size_of`
--> /home/gh-estebank/rust/library/core/src/mem/mod.rs:312:22
|
312 | pub const fn size_of<T>() -> usize {
| ^ required by the implicit `Sized` requirement on this bound in `size_of`
```
Fix#120178.
Since the only use of `TypeCx::bug` is in `Constructor::is_covered_by`,
it is tempting to return `false` instead of `Err()`, but that would
cause "non-exhaustive match" false positives.
Don't hash lints differently to non-lints.
`Diagnostic::keys`, which is used for hashing and equating diagnostics, has a surprising behaviour: it ignores children, but only for lints. This was added in #88493 to fix some duplicated diagnostics, but it doesn't seem necessary any more.
This commit removes the special case and only four tests have changed output, with additional errors. And those additional errors aren't exact duplicates, they're just similar. For example, in src/tools/clippy/tests/ui/same_name_method.rs we currently have this error:
```
error: method's name is the same as an existing method in a trait
--> $DIR/same_name_method.rs:75:13
|
LL | fn foo() {}
| ^^^^^^^^^^^
|
note: existing `foo` defined here
--> $DIR/same_name_method.rs:79:9
|
LL | impl T1 for S {}
| ^^^^^^^^^^^^^^^^
```
and with this change we also get this error:
```
error: method's name is the same as an existing method in a trait
--> $DIR/same_name_method.rs:75:13
|
LL | fn foo() {}
| ^^^^^^^^^^^
|
note: existing `foo` defined here
--> $DIR/same_name_method.rs:81:9
|
LL | impl T2 for S {}
|
```
I think printing this second argument is reasonable, possibly even preferable to hiding it. And the other cases are similar.
r? `@estebank`
Provide more context on derived obligation error primary label
Expand the primary span of E0277 when the immediate unmet bound is not what the user wrote:
```
error[E0277]: the trait bound `i32: Bar` is not satisfied
--> f100.rs:6:6
|
6 | <i32 as Foo>::foo();
| ^^^ the trait `Bar` is not implemented for `i32`, which is required by `i32: Foo`
|
help: this trait has no implementations, consider adding one
--> f100.rs:2:1
|
2 | trait Bar {}
| ^^^^^^^^^
note: required for `i32` to implement `Foo`
--> f100.rs:3:14
|
3 | impl<T: Bar> Foo for T {}
| --- ^^^ ^
| |
| unsatisfied trait bound introduced here
```
Fix#40120.
pattern_analysis: cleanup the contexts
This cleans up a bit the various `*Ctxt`s I had left lying around. As a bonus this made it possible to make `PatternColumn` public. I don't have a use for that yet but that could come useful.
`UsefulnessCtxt` looks useless right now but I'll be adding a field or two in subsequent PRs.
r? `````@compiler-errors`````
Further improve `space_between`
`space_between` is used by `print_tts` to decide when spaces should be put between tokens. This PR improves it in two ways:
- avoid unnecessary spaces before semicolons, and
- don't omit some necessary spaces before/after some punctuation symbols.
r? `@petrochenkov`
Disable packed/unpacked options for riscv linux/android.
Other riscv targets already only have the off option.
The packed/unpacked options might be supported in the future.
See upstream issue for more details:
https://github.com/llvm/llvm-project/issues/56642Fixes#110224
Expand the primary span of E0277 when the immediate unmet bound is not what the user wrote:
```
error[E0277]: the trait bound `i32: Bar` is not satisfied
--> f100.rs:6:6
|
6 | <i32 as Foo>::foo();
| ^^^ the trait `Bar` is not implemented for `i32`, which is required by `i32: Foo`
|
help: this trait has no implementations, consider adding one
--> f100.rs:2:1
|
2 | trait Bar {}
| ^^^^^^^^^
note: required for `i32` to implement `Foo`
--> f100.rs:3:14
|
3 | impl<T: Bar> Foo for T {}
| --- ^^^ ^
| |
| unsatisfied trait bound introduced here
```
Fix#40120.
`Diagnostic::keys`, which is used for hashing and equating diagnostics,
has a surprising behaviour: it ignores children, but only for lints.
This was added in #88493 to fix some duplicated diagnostics, but it
doesn't seem necessary any more.
This commit removes the special case and only four tests have changed
output, with additional errors. And those additional errors aren't
exact duplicates, they're just similar. For example, in
src/tools/clippy/tests/ui/same_name_method.rs we currently have this
error:
```
error: method's name is the same as an existing method in a trait
--> $DIR/same_name_method.rs:75:13
|
LL | fn foo() {}
| ^^^^^^^^^^^
|
note: existing `foo` defined here
--> $DIR/same_name_method.rs:79:9
|
LL | impl T1 for S {}
| ^^^^^^^^^^^^^^^^
```
and with this change we also get this error:
```
error: method's name is the same as an existing method in a trait
--> $DIR/same_name_method.rs:75:13
|
LL | fn foo() {}
| ^^^^^^^^^^^
|
note: existing `foo` defined here
--> $DIR/same_name_method.rs:81:9
|
LL | impl T2 for S {}
| ^^^^^^^^^^^^^^^^
```
I think printing this second argument is reasonable, possibly even
preferable to hiding it. And the other cases are similar.
When a method not found on a type parameter could have been provided by any
of multiple traits, suggest each trait individually, instead of a single
suggestion to restrict the type parameter with *all* of them.
Before:
```
error[E0599]: the method `cmp` exists for reference `&T`, but its trait bounds were not satisfied
--> $DIR/method-on-unbounded-type-param.rs:5:10
|
LL | (&a).cmp(&b)
| ^^^ method cannot be called on `&T` due to unsatisfied trait bounds
|
= note: the following trait bounds were not satisfied:
`T: Ord`
which is required by `&T: Ord`
`&T: Iterator`
which is required by `&mut &T: Iterator`
`T: Iterator`
which is required by `&mut T: Iterator`
help: consider restricting the type parameters to satisfy the trait bounds
|
LL | fn g<T>(a: T, b: T) -> std::cmp::Ordering where T: Iterator, T: Ord {
| +++++++++++++++++++++++++
```
After:
```
error[E0599]: the method `cmp` exists for reference `&T`, but its trait bounds were not satisfied
--> $DIR/method-on-unbounded-type-param.rs:5:10
|
LL | (&a).cmp(&b)
| ^^^ method cannot be called on `&T` due to unsatisfied trait bounds
|
= note: the following trait bounds were not satisfied:
`T: Ord`
which is required by `&T: Ord`
`&T: Iterator`
which is required by `&mut &T: Iterator`
`T: Iterator`
which is required by `&mut T: Iterator`
= help: items from traits can only be used if the type parameter is bounded by the trait
help: the following traits define an item `cmp`, perhaps you need to restrict type parameter `T` with one of them:
|
LL | fn g<T: Ord>(a: T, b: T) -> std::cmp::Ordering {
| +++++
LL | fn g<T: Iterator>(a: T, b: T) -> std::cmp::Ordering {
| ++++++++++
```
Fix#108428.
Normalize region obligation in lexical region resolution with next-gen solver
This normalizes region obligations when we `resolve_regions`, since they may be unnormalized with deferred projection equality.
It's pretty hard to add tests that exercise this without also triggering MIR borrowck errors (because we don't normalize there yet). I've added one test with two revisions that should test that we both 1. normalize region obligations in the param env, and 2. normalize registered region obligations during lexical region resolution.
When encountering
```rust
fn f<T>(a: T, b: T) -> std::cmp::Ordering {
a.cmp(&b) //~ ERROR E0599
}
```
output
```
error[E0599]: no method named `cmp` found for type parameter `T` in the current scope
--> $DIR/method-on-unbounded-type-param.rs:2:7
|
LL | fn f<T>(a: T, b: T) -> std::cmp::Ordering {
| - method `cmp` not found for this type parameter
LL | a.cmp(&b)
| ^^^ method cannot be called on `T` due to unsatisfied trait bounds
|
= help: items from traits can only be used if the type parameter is bounded by the trait
help: the following traits define an item `cmp`, perhaps you need to restrict type parameter `T` with one of them:
|
LL | fn f<T: Ord>(a: T, b: T) -> std::cmp::Ordering {
| +++++
LL | fn f<T: Iterator>(a: T, b: T) -> std::cmp::Ordering {
| ++++++++++
```
Fix#120186.
Remove some unnecessary check logic for lang items in HIR typeck
Obvious bugs with `#[no_core]` do not deserve customized recovery logic, since they are bugs we do not expect users to ever encounter, and if users are experimenting with `#[no_core]`, they should really be familiar with the compiler implementation.
These error recoveries are implemented now only where issues have been reported in the past, rather than systematically validating lang items.
See https://github.com/rust-lang/compiler-team/issues/620
> In particular, one-off fixes for particular assumptions about lang items or intrinsics that introduce additional complexity into the compiler are not accepted.
r? Nilstrieb
Improve error message when `cargo build` is used to build the compiler
Inspired by #76446.
Doing it for `core` is probably higher value but also way harder because tools like cargo or rustc-build-sysroot would need to be fixed first, which I don't feel like doing.
Revert outdated version of "Add the wasm32-wasi-preview2 target"
An outdated version of #119616 was merged in rollup #120309.
This reverts those changes to enable #119616 to “retain the intended diff” after a rebase.
```@rylev``` has agreed that this would be the cleanest approach with respect to the history.
Unblocks #119616.
r? ```@petrochenkov``` or compiler or libs
Remove various `has_errors` or `err_count` uses
follow up to https://github.com/rust-lang/rust/pull/119895
r? `@nnethercote` since you recently did something similar.
There are so many more of these, but I wanted to get a PR out instead of growing the commit list indefinitely. The commits all work on their own and can be reviewed commit by commit.
Deduplicate more sized errors on call exprs
Change the implicit `Sized` `Obligation` `Span` for call expressions to include the whole expression. This aids the existing deduplication machinery to reduce the number of errors caused by a single unsized expression.
Suppress unhelpful diagnostics for unresolved top level attributes
Fixes#118455, unresolved top level attribute error didn't imported prelude and already have emitted an error, report builtin macro and attributes error by the way, so `check_invalid_crate_level_attr` in can ignore them.
Also fixes#89566, fixes#67107.
r? `@petrochenkov`
The query accept arbitrary DefIds, not just owner DefIds.
The return can be an `Option` because if there are no nodes, then it doesn't matter whether it's due to NonOwner or Phantom.
Also rename the query to `opt_hir_owner_nodes`.
Be more careful about interpreting a label/lifetime as a mistyped char literal.
Currently the parser interprets any label/lifetime in certain positions as a mistyped char literal, on the assumption that the trailing single quote was accidentally omitted. In such cases it gives an error with a suggestion to add the trailing single quote, and then puts the appropriate char literal into the AST. This behaviour was introduced in #101293.
This is reasonable for a case like this:
```
let c = 'a;
```
because `'a'` is a valid char literal. It's less reasonable for a case like this:
```
let c = 'abc;
```
because `'abc'` is not a valid char literal.
Prior to #120329 this could result in some sub-optimal suggestions in error messages, but nothing else. But #120329 changed `LitKind::from_token_lit` to assume that the char/byte/string literals it receives are valid, and to assert if not. This is reasonable because the lexer does not produce invalid char/byte/string literals in general. But in this "interpret label/lifetime as unclosed char literal" case the parser can produce an invalid char literal with contents such as `abc`, which triggers an assertion failure.
This PR changes the parser so it's more cautious about interpreting labels/lifetimes as unclosed char literals.
Fixes#120397.
r? `@compiler-errors`
Fixes footnote handling in rustdoc
Fixes#100638.
You can now declare footnotes like this:
```rust
//! Reference to footnotes A[^1], B[^2] and C[^3].
//!
//! [^1]: Footnote A.
//! [^2]: Footnote B.
//! [^3]: Footnote C.
```
r? `@notriddle`
Make the coroutine def id of an async closure the child of the closure def id
Adjust def collection to make the (inner) coroutine returned by an async closure be a def id child of the (outer) closure. This makes it easy to map from coroutine -> closure by using `tcx.parent`, since currently it's not trivial to do this.
Because it's almost always static.
This makes `impl IntoDiagnosticArg for DiagnosticArgValue` trivial,
which is nice.
There are a few diagnostics constructed in
`compiler/rustc_mir_build/src/check_unsafety.rs` and
`compiler/rustc_mir_transform/src/errors.rs` that now need symbols
converted to `String` with `to_string` instead of `&str` with `as_str`,
but that' no big deal, and worth it for the simplifications elsewhere.
only assemble alias bound candidates for rigid aliases
fixes https://github.com/rust-lang/trait-system-refactor-initiative/issues/77
This also causes `<Wrapper<?0> as Trait>::Unwrap: Trait` to always be ambig, as we now normalize the self type before checking whether it is an inference variable.
I cannot think of an approach to the underlying issues here which does not require the "may-define means must-define" restriction for opaque types. Going to go ahead with this and added this restriction to the tracking issue for the new solver to make sure we don't stabilize it without getting types + lang signoff here.
r? `@compiler-errors`
Do not attempt to provide an accurate suggestion for `impl Trait`
in bare trait types when linting. Instead, only do the object
safety check when an E0782 is already going to be emitted in the
2021 edition.
Fix#120241.
Borrow check inline const patterns
Add type annotations to MIR so that borrowck can pass constraints from inline constants in patterns to the containing function.
Also enables some inline constant pattern tests that were fixed by the THIR unsafeck stabilization.
cc #76001
Improve handling of expressions in patterns
Closes#112593.
Methodcalls' dots in patterns are silently recovered as commas (e.g. `Foo("".len())` -> `Foo("", len())`) so extra diagnostics are emitted:
```rs
struct Foo(u8, String, u8);
fn bar(foo: Foo) -> bool {
match foo {
Foo(4, "yippee".yeet(), 7) => true,
_ => false
}
}
```
```
error: expected one of `)`, `,`, `...`, `..=`, `..`, or `|`, found `.`
--> main.rs:5:24
|
5 | Foo(4, "yippee".yeet(), 7) => true,
| ^
| |
| expected one of `)`, `,`, `...`, `..=`, `..`, or `|`
| help: missing `,`
error[E0531]: cannot find tuple struct or tuple variant `yeet` in this scope
--> main.rs:5:25
|
5 | Foo(4, "yippee".yeet(), 7) => true,
| ^^^^ not found in this scope
error[E0023]: this pattern has 4 fields, but the corresponding tuple struct has 3 fields
--> main.rs:5:13
|
1 | struct Foo(u8, String, u8);
| -- ------ -- tuple struct has 3 fields
...
5 | Foo(4, "yippee".yeet(), 7) => true,
| ^ ^^^^^^^^ ^^^^^^ ^ expected 3 fields, found 4
error: aborting due to 3 previous errors
```
This PR checks for patterns that ends with a dot and a lowercase ident (as structs/variants should be uppercase):
```
error: expected a pattern, found a method call
--> main.rs:5:16
|
5 | Foo(4, "yippee".yeet(), 7) => true,
| ^^^^^^^^^^^^^^^ method calls are not allowed in patterns
error: aborting due to 1 previous error
```
Also check for expressions:
```rs
fn is_idempotent(x: f32) -> bool {
match x {
x * x => true,
_ => false,
}
}
fn main() {
let mut t: [i32; 5];
let t[0] = 1;
}
```
```
error: expected a pattern, found an expression
--> main.rs:3:9
|
3 | x * x => true,
| ^^^^^ arbitrary expressions are not allowed in patterns
error: expected a pattern, found an expression
--> main.rs:10:9
|
10 | let t[0] = 1;
| ^^^^ arbitrary expressions are not allowed in patterns
```
Would be cool if the compiler could suggest adding a guard for `match`es, but I've no idea how to do it.
---
`@rustbot` label +A-diagnostics +A-parser +A-patterns +C-enhancement
