Replace `&Vec<_>`s with `&[_]`s
It's generally preferable to use `&[_]` since it's one less indirection and it can be created from types other that `Vec`.
I've left `&Vec` in some locals where it doesn't really matter, in cases where `TypeFoldable` is expected (`TypeFoldable: Clone` so slice can't implement it) and in cases where it's `&TypeAliasThatIsActiallyVec`. Nothing important, really, I was just a little annoyed by `visit_generic_param_vec` :D
r? `@compiler-errors`
Iterate over `maybe_unused_trait_imports` when checking dead trait imports
Closes#96873
r? `@cjgillot`
Some questions, if you have time:
- Is there a way to shorten the `rustc_data_structures::fx::FxIndexSet` path in the query declaration? I wasn't sure where to put a `use`.
- Was returning by reference from the query the right choice here?
- How would I go about evaluating the importance of the `is_dummy()` call in `check_crate`? I don't see failing tests when I comment it out. Should I just try to determine whether dummy spans can ever be put into `maybe_unused_trait_imports`?
- Am I doing anything silly with the various ID types?
- Is that `let-else` with `unreachable!()` bad? (i.e is there a better idiom? Would `panic!("<explanation>")` be better?)
- If I want to evaluate the perf of using a `Vec` as mentioned in #96873, is the best way to use the CI or is it feasible locally?
Thanks :)
Remove all json handling from rustc_serialize
Json is now handled using serde_json. Where appropriate I have replaced json usage with binary serialization (rmeta files) or manual string formatting (emcc linker arg generation).
This allowed for removing and simplifying a lot of code, which hopefully results in faster serialization/deserialization and faster compiles of rustc itself.
Where sensible we now use serde. Metadata and incr cache serialization keeps using a heavily modified (compared to crates.io) rustc-serialize version that in the future could probably be extended with zero-copy deserialization or other perf tricks that serde can't support due to supporting more than one serialization format.
Note that I had to remove `-Zast-json` and `-Zast-json-noexpand` as the relevant AST types don't implement `serde::Serialize`.
Fixes#40177
See also https://github.com/rust-lang/compiler-team/issues/418
Compute `is_late_bound_map` query separately from lifetime resolution
This query is actually very simple, and is only useful for functions and method. It can be computed directly by fetching the HIR, with no need to embed it within the lifetime resolution visitor.
Based on https://github.com/rust-lang/rust/pull/96296
rewrite error handling for unresolved inference vars
Pretty much completely rewrites `fn emit_inference_failure_err`.
This new setup should hopefully be easier to extend and is already a lot better when looking for generic arguments.
Because this is a rewrite there are still some parts which are lacking, these are tracked in #94483 and will be fixed in later PRs.
r? `@estebank` `@petrochenkov`
On E0204 suggest missing type param bounds
```
error[E0204]: the trait `Copy` may not be implemented for this type
--> f42.rs:9:17
|
9 | #[derive(Debug, Copy, Clone)]
| ^^^^
10 | pub struct AABB<K>{
11 | pub loc: Vector2<K>,
| ------------------- this field does not implement `Copy`
12 | pub size: Vector2<K>
| -------------------- this field does not implement `Copy`
|
note: the `Copy` impl for `Vector2<K>` requires that `K: Debug`
--> f42.rs:11:5
|
11 | pub loc: Vector2<K>,
| ^^^^^^^^^^^^^^^^^^^
note: the `Copy` impl for `Vector2<K>` requires that `K: Debug`
--> f42.rs:12:5
|
12 | pub size: Vector2<K>
| ^^^^^^^^^^^^^^^^^^^^
= note: this error originates in the derive macro `Copy` (in Nightly builds, run with -Z macro-backtrace for more info)
help: consider restricting type parameter `K`
|
10 | pub struct AABB<K: Debug>{
| +++++++
```
Fix#89137.
```
error[E0204]: the trait `Copy` may not be implemented for this type
--> f42.rs:9:17
|
9 | #[derive(Debug, Copy, Clone)]
| ^^^^
10 | pub struct AABB<K>{
11 | pub loc: Vector2<K>,
| ------------------- this field does not implement `Copy`
12 | pub size: Vector2<K>
| -------------------- this field does not implement `Copy`
|
note: the `Copy` impl for `Vector2<K>` requires that `K: Debug`
--> f42.rs:11:5
|
11 | pub loc: Vector2<K>,
| ^^^^^^^^^^^^^^^^^^^
note: the `Copy` impl for `Vector2<K>` requires that `K: Debug`
--> f42.rs:12:5
|
12 | pub size: Vector2<K>
| ^^^^^^^^^^^^^^^^^^^^
= note: this error originates in the derive macro `Copy` (in Nightly builds, run with -Z macro-backtrace for more info)
help: consider restricting type parameter `K`
|
10 | pub struct AABB<K: Debug>{
| +++++++
```
Fix#89137.
Diagnose anonymous lifetimes errors more uniformly between async and regular fns
Async fns and regular fns are desugared differently. For the former, we create a generic parameter at HIR level. For the latter, we just create an anonymous region for typeck.
I plan to migrate regular fns to the async fn desugaring.
Before that, this PR attempts to merge the diagnostics for both cases.
r? ```@estebank```
Add validation layer for Derefer
_Follow up work to #96549#96116#95857 #95649_
This adds validation for Derefer making sure it is always the first projection.
r? rust-lang/mir-opt
Replace `#[default_method_body_is_const]` with `#[const_trait]`
pulled out of #96077
related issues: #67792 and #92158
cc `@fee1-dead`
This is groundwork to only allowing `impl const Trait` for traits that are marked with `#[const_trait]`. This is necessary to prevent adding a new default method from becoming a breaking change (as it could be a non-const fn).
Finish bumping stage0
It looks like the last time had left some remaining cfg's -- which made me think
that the stage0 bump was actually successful. This brings us to a released 1.62
beta though.
This now brings us to cfg-clean, with the exception of check-cfg-features in bootstrap;
I'd prefer to leave that for a separate PR at this time since it's likely to be more tricky.
cc https://github.com/rust-lang/rust/pull/97147#issuecomment-1132845061
r? `@pietroalbini`
Update to rebased rustc-rayon 0.4
In rayon-rs/rayon#938, miri uncovered a race in `rustc-rayon-core` that had already been fixed in the regular `rayon-core`. I have now rebased that fork onto the latest rayon branch, and published as 0.4. I also updated `indexmap` to bump the dependency.
`Cargo.lock` changes:
Updating indexmap v1.8.0 -> v1.8.2
Updating rayon v1.5.1 -> v1.5.3
Updating rayon-core v1.9.1 -> v1.9.3
Updating rustc-rayon v0.3.2 -> v0.4.0
Updating rustc-rayon-core v0.3.2 -> v0.4.1
Try to cache region_scope_tree as a query
This PR will attempt to restore `region_scope_tree` as a query so that caching works again. It seems that `region_scope_tree` could be re-computed for nested items after all, which could explain the performance regression introduced by #95563.
cc `@Mark-Simulacrum` `@pnkfelix` I will try to trigger a perf run here.
Split dead store elimination off dest prop
This splits off a part of #96451 . I've added this in as its own pass for now, so that it actually runs, can be tested, etc. In the dest prop PR, I'll stop invoking this as its own pass, so that it doesn't get invoked twice.
r? `@tmiasko`
Add suggestion for relaxing static lifetime bounds on dyn trait impls in NLL
This PR introduces suggestions for relaxing static lifetime bounds on impls of dyn trait items for NLL similar to what is already available in lexical region diagnostics.
Fixes https://github.com/rust-lang/rust/issues/95701
r? `@estebank`
It looks like the last time had left some remaining cfg's -- which made me think
that the stage0 bump was actually successful. This brings us to a released 1.62
beta though.
Move various checks to typeck so them failing causes the typeck result to get tainted
Fixes#69487fixes#79047
cc `@RalfJung` this gets rid of the `Transmute` invalid program error variant
add a deep fast_reject routine
continues the work on #97136.
r? `@nnethercote`
Actually agree with you on the match structure 😆 let's see how that impacted perf 😅
When constructing a MIR from a THIR field expression, introduce an
additional downcast projection before accessing a field of an enum.
When rebasing a place builder on top of a captured place, account for
the fact that a single HIR enum field projection corresponds to two MIR
projection elements: a downcast element and a field element.
Lifetime variance fixes for rustc
#97287 migrates rustc to a `Ty` type that is invariant over its lifetime `'tcx`, so I need to fix a bunch of places that assume that `Ty<'a>` and `Ty<'b>` can be unified by shortening both to some common lifetime.
This is doable, since many lifetimes are already `'tcx`, so all this PR does is be a bit more explicit that elided lifetimes are actually `'tcx`.
Split out from #97287 so the compiler team can review independently.
Move the extended lifetime resolution into typeck context
Related to #15023
This PR is based on the [idea](https://github.com/rust-lang/rust/issues/15023#issuecomment-1070931433) of #15023 by `@nikomatsakis.`
This PR specifically proposes to
- Delay the resolution of scopes of rvalues to a later stage, so that enough type information is available to refine those scopes based on relationships of lifetimes.
- Highlight relevant parts that would help future reviews on the next installments of works to fully implement a solution to RFC 66.
Implement proper stability check for const impl Trait, fall back to unstable const when undeclared
Continuation of #93960
`@jhpratt` it looks to me like the test was simply not testing for the failure you were looking for? Your checks actually do the right thing for const traits?
correctly deal with user type ascriptions in pat
supersedes #93856
`thir::PatKind::AscribeUserType` previously resulted in `CanonicalUserTypeAnnotations` where the inferred type already had a subtyping relation according to `variance` to the `user_ty`.
The bug can pretty much be summarized as follows:
- during mir building
- `user_ty -> inferred_ty`: considers variance
- `StatementKind::AscribeUserType`: `inferred_ty` is the type of the place, so no variance needed
- during mir borrowck
- `user_ty -> inferred_ty`: does not consider variance
- `StatementKind::AscribeUserType`: applies variance
This mostly worked fine. The lifetimes in `inferred_ty` were only bound by its relation to `user_ty` and to the `place` of `StatementKind::AscribeUserType`, so it doesn't matter where exactly the subtyping happens.
It does however matter when having higher ranked subtying. At this point the place where the subtyping happens is forced, causing this mismatch between building and borrowck to result in unintended errors.
cc #96514 which is pretty much the same issue
r? `@nikomatsakis`
Remove `crate` visibility modifier
FCP to remove this syntax is just about complete in #53120. Once it completes, this should be merged ASAP to avoid merge conflicts.
The first two commits remove usage of the feature in this repository, while the last removes the feature itself.
Cache more queries on disk
One of the principles of incremental compilation is to allow saving results on disk to avoid recomputing them.
This PR investigates persisting a lot of queries whose result are to be saved into metadata.
Some of the queries are cheap reads from HIR, but we may also want to get rid of these reads for incremental lowering.
Rollup of 6 pull requests
Successful merges:
- #96565 (rustdoc: show implementations on `#[fundamental]` wrappers)
- #97179 (Add new lint to enforce whitespace after keywords)
- #97185 (interpret/validity: separately control checking numbers for being init and non-ptr)
- #97188 (Remove unneeded null pointer asserts in ptr2int casts)
- #97189 (Update .mailmap)
- #97192 (Say "last" instead of "rightmost" in the documentation for `std::str:rfind`)
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
interpret/validity: separately control checking numbers for being init and non-ptr
This lets Miri control this in a more fine-grained way.
r? `@oli-obk`
`simplify_type` improvements and cursed docs
the existing `TreatParams` enum pretty much mixes everything up. Not sure why this looked right to me in #94057
This also includes two changes which impact perf:
- `ty::Projection` with inference vars shouldn't be treated as a rigid type, even if fully normalized
- `ty::Placeholder` only unifies with itself, so actually return `Some` for them
r? `@nikomatsakis`
Rather than deferring to const eval for checking if a trait is const, we
now check up-front. This allows the error to be emitted earlier, notably
at the same time as other stability checks.
Also included in this commit is a change of the default const stability
level to UNstable. Previously, an item that was `const` but did not
explicitly state it was unstable was implicitly stable.
Prevent unwinding when `-C panic=abort` is used regardless declared ABI
Ensures that Rust code will abort with `-C panic=abort` regardless ABI used.
```rust
extern "C-unwind" {
fn may_unwind();
}
// Will be nounwind with `-C panic=abort`, despite `C-unwind` ABI.
pub unsafe extern "C-unwind" fn rust_item_that_can_unwind() {
may_unwind();
}
```
Current behaviour is that unwind will propagate through. While the current behaviour won't cause unsoundness it is inconsistent with the text reading of [RFC2945](https://rust-lang.github.io/rfcs/2945-c-unwind-abi.html).
I tweaked `fn_can_unwind` instead of tweaking `AbortUnwindingCalls` because this approach would allow Rust (non-direct) callers to also see that this function is nounwind, so it can prevent excessive landing pads generation.
For more discussions: https://rust-lang.zulipchat.com/#narrow/stream/210922-project-ffi-unwind/topic/soundness.20in.20mixed.20panic.20mode.
cc `@alexcrichton,` `@BatmanAoD`
r? `@Amanieu`
`@rustbot` label: T-compiler T-lang F-c_unwind
Change `Successors` to `impl Iterator<Item = BasicBlock>`
This PR fixes the FIXME in `compiler\rustc_middle\src\mir\mod.rs`.
This can omit several `&`, `*` or `cloned` operations on Successros' generated elements
Add a query for checking whether a function is an intrinsic.
work towards #93145
This will reduce churn when we add more ways to declare intrinsics
r? `@scottmcm`
