Avoid accidentally enabling unstable features in compilers (take 2)
This allows rustbuild to control whether crates can use nightly features or not.
It also prevents rustbuild from using nightly features itself.
This is #92261, but I fixed the CI error.
Do leak check after function pointer coercion
cc #73154
I still need to clean diagnostics just a tad, but figured I would put this up anyways.
This change is made in order to make match arm coercion order-independent.
Basically, any time we do function pointer coercion, we follow it by doing a leak check. This is necessary because the LUB code doesn't handler higher-ranked things correctly, leading us to "coerce", but use the wrong type. A proper fix is to actually fix that code (so the type returned by `unify_and` is a supertype of both `a` and `b` if `Ok`). However, that requires a more in-depth fix, likely heavily overlapping with the new subtyping changes.
Here, I've been conservative and error early if we generate unsatisfiable constraints. Note, this should *mostly* only affect NLL, since migrate mode falls back to the LUB implementation (followed by leak check), whereas NLL only does sub.
There could be other coercion code that has an order-dependence where a leak check in the coercion code might be useful. However, this is more of a spot-fix for #73154 than a "permanent" fix, since we likely want to go the other way long-term, and allow this pattern without error.
r? `@nikomatsakis`
rustc_parse: Move AST -> TokenStream conversion logic to rustc_ast
In the past falling back to reparsing pretty-printed strings was common, so some of this logic had to live in `rustc_parse`, but now the reparsing fallback is only used in two corner cases so we can move this logic to `rustc_ast` which makes many things simpler.
It also helps to fix `MacArgs::inner_tokens` for `MacArgs::Eq` with non-literal expressions, which is done in the second commit.
r? `@nnethercote`
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?
Fix typo in futex RwLock::write_contended.
I wrote `state` where I should've used `s`.
This was spotted by `@Warrenren.`
This change removes the unnecessary `s` variable to prevent that mistake.
Fortunately, this typo didn't affect the correctness of the lock, as the
second half of the condition (!has_writers_waiting) is enough for
correctness, which explains why this mistake didn't show up during
testing.
Fixes https://github.com/rust-lang/rust/issues/97162
Omit stdarch workspace from rust-src
The path `library/stdarch/crates/Cargo.toml` does not exist.
In Rust 1.61.0, `rust-src` still includes `src/rust/library/stdarch/Cargo.toml` (but not `stdarch-verify`), which includes
```toml
[workspace]
members = [
"crates/stdarch-verify"
```
This didn't show up when testing with `-Zbuild-std` in https://github.com/rust-lang/rust/pull/94907 since the [standard list of crates](f624095e1c/src/cargo/core/compiler/standard_lib.rs (L26-L30)) to include when building `std` does not include `stdarch`, but it will show up if a user explicitly requests `stdarch`. Or, perhaps more importantly, because of https://github.com/rust-lang/rust/issues/95736, many editors (like IntelliJ) won't treat the root of `rust-src` as a workspace, and will instead recurse into all the sub-crates directly, which then includes `stdarch`.
Also related to https://github.com/rust-lang/rust/issues/94906.
Fix `Display` for `cell::{Ref,RefMut}`
These guards changed to pointers in #97027, but their `Display` was
formatting that field directly, which made it show the raw pointer
value. Now we go through `Deref` to display the real value again.
Miri noticed this change, #97204, so hopefully that will be fixed.
Fix rusty grammar in `std::error::Reporter` docs
### Commit
I initially saw "print's" instead of "prints" at the start of the doc comment for `std::error::Reporter`, while reading the docs for that type. Then I figured 'probably more where that came from', so, as well as correcting the foregoing to "prints", I've patched up these three minor solecisms (well, two [types](https://en.wikipedia.org/wiki/Type%E2%80%93token_distinction), three [tokens](https://en.wikipedia.org/wiki/Type%E2%80%93token_distinction)):
- One use of the indicative which should be subjunctive - indeed the sentence immediately following it, which mirrors its structure, _does_ use the subjunctive ([L871](https://github.com/rust-lang/rust/blob/master/library/std/src/error.rs?plain=1#L871)). Replaced with the subjunctive.
- Two separate clauses joined with commas ([L975](https://github.com/rust-lang/rust/blob/master/library/std/src/error.rs?plain=1#L975), [L1023](https://github.com/rust-lang/rust/blob/master/library/std/src/error.rs?plain=1#L1023)). Replaced the first with a semicolon and the second with a period. Admittedly those judgements are pretty much 100% subjective, based on my sense of how the sentences flowed into each other (though ofc the _replacement of the comma itself_ is not subjective or opinion-based).
I know this is silly and finicky, but I hope it helps tidy up the docs a bit for future readers!
### PR notes
**This is very much non-urgent (and, honestly, non-important).** I just figured it might be a nice quality-of-life improvement and bit of tidying up for the core contributors themselves not to have to do. 🙂
I'm tagging Steve, per the [contributing guidelines](https://rustc-dev-guide.rust-lang.org/contributing.html#r) ("Steve usually reviews documentation changes. So if you were to make a documentation change, add `r? `@steveklabnik`"):`
r? `@steveklabnik`
Stabilize `array_from_fn`
## Overall
Stabilizes `core::array::from_fn` ~~and `core::array::try_from_fn`~~ to allow the creation of custom infallible ~~and fallible~~ arrays.
Signature proposed for stabilization here, tweaked as requested in the meeting:
```rust
// in core::array
pub fn from_fn<T, const N: usize, F>(_: F) -> [T; N];
```
Examples in https://doc.rust-lang.org/nightly/std/array/fn.from_fn.html
## History
* On 2020-08-17, implementation was [proposed](https://github.com/rust-lang/rust/pull/75644).
* On 2021-09-29, tracking issue was [created](https://github.com/rust-lang/rust/issues/89379).
* On 2021-10-09, the proposed implementation was [merged](bc8ad24020).
* On 2021-12-03, the return type of `try_from_fn` was [changed](https://github.com/rust-lang/rust/pull/91286#issuecomment-985513407).
## Considerations
* It is being assumed that indices are useful and shouldn't be removed from the callbacks
* The fact that `try_from_fn` returns an unstable type `R: Try` does not prevent stabilization. Although I'm honestly not sure about it.
* The addition or not of repeat-like variants is orthogonal to this PR.
These considerations are not ways of saying what is better or what is worse. In reality, they are an attempt to move things forward, anything really.
cc https://github.com/rust-lang/rust/issues/89379
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`
Implement Copy, Clone, PartialEq and Eq for core::fmt::Alignment
Alignment is a fieldless exhaustive enum, so it is already possible to
clone and compare it by matching, but it is inconvenient to do so. For
example, if one would like to create a struct describing a formatter
configuration and provide a clone implementation:
```rust
pub struct Format {
fill: char,
width: Option<usize>,
align: fmt::Alignment,
}
impl Clone for Format {
fn clone(&self) -> Self {
Format {
align: match self.align {
fmt::Alignment::Left => fmt::Alignment::Left,
fmt::Alignment::Right => fmt::Alignment::Right,
fmt::Alignment::Center => fmt::Alignment::Center,
},
.. *self
}
}
}
```
Derive Copy, Clone, PartialEq, and Eq for Alignment for convenience.
Rollup of 7 pull requests
Successful merges:
- #97190 (Add implicit call to from_str via parse in documentation)
- #97218 (Add eslint checks)
- #97219 (make ptr::invalid not the same as a regular int2ptr cast)
- #97223 (Remove quadratic behaviour from -Zunpretty=hir-tree.)
- #97232 (typo)
- #97237 (Add some more weird-exprs)
- #97238 (Bump LLVM fetched from CI to fix run-make)
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
Bump LLVM fetched from CI to fix run-make
cc `@yaahc,` who found this while testing locally
Ideally we'd detect this in CI and catch it, but at least we have a comment now which should hopefully prevent this from happening in the future.
r? `@pietroalbini` or `@jyn514`
Add some more weird-exprs
Continuing from https://github.com/rust-lang/rust/pull/86713 (which stalled due to a thinking emoji), I'd like to "improve" the `weird-exprs.rs`-file (as I can't reopen that PR).
make ptr::invalid not the same as a regular int2ptr cast
In Miri, we would like to distinguish `ptr::invalid` from `ptr::from_exposed_provenance`, so that we can provide better diagnostics issues like https://github.com/rust-lang/miri/issues/2134, and so that we can detect the UB in programs like
```rust
fn main() {
let x = 0u8;
let original_ptr = &x as *const u8;
let addr = original_ptr.expose_addr();
let new_ptr: *const u8 = core::ptr::invalid(addr);
unsafe {
dbg!(*new_ptr);
}
}
```
To achieve that, the two functions need to have different implementations. Currently, both are just `as` casts. We *could* add an intrinsic for this, but it turns out `transmute` already has the right behavior, at least as far as Miri is concerned. So I propose we just use that.
Cc `@Gankra`
Add eslint checks
The first check is to ensure that `=>` is always surrounded with whitespaces.
The second is to ensure that the dict objects looks like this: `{"a": 2}` and not `{"a" : 2}` or `{"a":2}`.
r? ``@notriddle``
Add implicit call to from_str via parse in documentation
The documentation mentions "FromStr’s from_str method is often used implicitly,
through str’s parse method. See parse’s documentation for examples.".
It may be nicer to show that in the code example as well.
I wrote `state` where I should've used `s`.
This removes the unnecessary `s` variable to prevent that mistake.
Fortunately, this typo didn't affect the correctness of the lock, as the
second half of the condition (!has_writers_waiting) is enough for
correctness, which explains why this mistake didn't show up during
testing.
rustdoc: Reduce clean::Type size
There is no need to keep the `DefId` around since it's allow used to compute if we should show a cast or not. As such, we can simply directly store the boolean.
I think it's not what you had in mind `@camelid` but I guess it's still an improvement? 😉
It was discussed in https://github.com/rust-lang/rust/pull/93941.
r? `@camelid`
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.
