Discovered in our experimental rust + llvm at head ci:
https://buildkite.com/llvm-project/rust-llvm-integrate-prototype/builds/12104#0182195b-8791-4f88-853c-bb23a1e4b54c
Rollup merge of #99480 - miam-miam100:arg-format, r=oli-obk
Diagnostic width span is not added when '0$' is used as width in format strings
When the following code is run rustc does not add diagnostic spans for the width argument. Such spans are necessary for a clippy lint that I am currently writing.
```rust
println!("Hello {1:0$}!", 5, "x");
// ^^
// Should have a span here
```
Rollup merge of #99212 - davidtwco:partial-stability-implies, r=michaelwoerister
introduce `implied_by` in `#[unstable]` attribute
Requested by the library team [on Zulip](https://rust-lang.zulipchat.com/#narrow/stream/131828-t-compiler/topic/better.20support.20for.20partial.20stabilizations/near/285581519).
If part of a feature is stabilized and a new feature is added for the remaining parts, then the `implied_by` meta-item can be added to `#[unstable]` to indicate which now-stable feature was used previously.
```diagnostic
error: the feature `foo` has been partially stabilized since 1.62.0 and is succeeded by the feature `foobar`
--> $DIR/stability-attribute-implies-using-unstable.rs:3:12
|
LL | #![feature(foo)]
| ^^^
|
note: the lint level is defined here
--> $DIR/stability-attribute-implies-using-stable.rs:2:9
|
LL | #![deny(stable_features)]
| ^^^^^^^^^^^^^^^
help: if you are using features which are still unstable, change to using `foobar`
|
LL | #![feature(foobar)]
| ~~~~~~
help: if you are using features which are now stable, remove this line
|
LL - #![feature(foo)]
|
```
When a `#![feature(..)]` attribute still exists for the now-stable attribute, then there this has two effects:
- There will not be an stability error for uses of items from the implied feature which are still unstable (until the `#![feature(..)]` is removed or updated to the new feature).
- There will be an improved diagnostic for the remaining use of the feature attribute for the now-stable feature.
```rust
/// If part of a feature is stabilized and a new feature is added for the remaining parts,
/// then the `implied_by` attribute is used to indicate which now-stable feature previously
/// contained a item.
///
/// ```pseudo-Rust
/// #[unstable(feature = "foo", issue = "...")]
/// fn foo() {}
/// #[unstable(feature = "foo", issue = "...")]
/// fn foobar() {}
/// ```
///
/// ...becomes...
///
/// ```pseudo-Rust
/// #[stable(feature = "foo", since = "1.XX.X")]
/// fn foo() {}
/// #[unstable(feature = "foobar", issue = "...", implied_by = "foo")]
/// fn foobar() {}
/// ```
```
In the Zulip discussion, this was envisioned as `implies` on `#[stable]` but I went with `implied_by` on `#[unstable]` because it means that only the unstable attribute needs to be changed in future, not the new stable attribute, which seems less error-prone. It also isn't particularly feasible for me to detect whether items from the implied feature are used and then only suggest updating _or_ removing the `#![feature(..)]` as appropriate, so I always do both.
There's some new information in the cross-crate metadata as a result of this change, that's a little unfortunate, but without requiring that the `#[unstable]` and `#[stable]` attributes both contain the implication information, it's necessary:
```rust
/// This mapping is necessary unless both the `#[stable]` and `#[unstable]` attributes should
/// specify their implications (both `implies` and `implied_by`). If only one of the two
/// attributes do (as in the current implementation, `implied_by` in `#[unstable]`), then this
/// mapping is necessary for diagnostics. When a "unnecessary feature attribute" error is
/// reported, only the `#[stable]` attribute information is available, so the map is necessary
/// to know that the feature implies another feature. If it were reversed, and the `#[stable]`
/// attribute had an `implies` meta item, then a map would be necessary when avoiding a "use of
/// unstable feature" error for a feature that was implied.
```
I also change some comments to documentation comments in the compiler, add a helper for going from a `Span` to a `Span` for the entire line, and fix a incorrect part of the pre-existing stability attribute diagnostics.
David Wood [Wed, 13 Jul 2022 14:10:19 +0000 (15:10 +0100)]
passes: improved partial stabilization diagnostic
Improves the diagnostic when a feature attribute is specified
unnecessarily but the feature implies another (i.e. it was partially
stabilized) to refer to the implied feature.
David Wood [Wed, 13 Jul 2022 14:02:23 +0000 (15:02 +0100)]
span: add `span_extend_to_line` helper
Adds a simple helper function to the `SourceMap` for extending a `Span`
to encompass the entire line it is on - useful for suggestions where
removing a line is the suggested action.
David Wood [Wed, 13 Jul 2022 12:10:37 +0000 (13:10 +0100)]
middle: add `implies_by` to `#[unstable]`
If part of a feature is stabilized and a new feature is added for the
remaining parts, then the `implied_by` attribute can be used to indicate
which now-stable feature previously contained a item. If the now-stable
feature is still active (if the user has only just updated rustc, for
example) then there will not be an stability error for uses of the item
from the implied feature.
Auto merge of #99506 - Dylan-DPC:rollup-q3msucx, r=Dylan-DPC
Rollup of 7 pull requests
Successful merges:
- #98101 (stdlib support for Apple WatchOS)
- #99345 (Do not allow typeck children items to constrain outer RPITs)
- #99383 (Formalize defining_use_anchor)
- #99436 (Add flag to configure `noalias` on `Box<T>`)
- #99483 (Fix a numerical underflow in tuple wrap suggestion)
- #99485 (Stop injecting `#[allow(unused_qualifications)]` in generated `derive` implementations)
- #99486 (Refactor: remove a string comparison between types in `check_str_addition`)
Discovered in our experimental rust + llvm at head ci:
https://buildkite.com/llvm-project/rust-llvm-integrate-prototype/builds/12104#0182195b-8791-4f88-853c-bb23a1e4b54c
Rollup merge of #99485 - mdholloway:unused-qualifications-in-derive, r=oli-obk
Stop injecting `#[allow(unused_qualifications)]` in generated `derive` implementations
Currently, the `#[derive]` attribute always injects an `#[allow(unused_qualifications)]` attribute in the generated implementation. This results in an error when a derive is used in combination with `#![forbid(unused_qualifications)]`, because the `forbid` rule by definition cannot be overridden by `allow`.
It appears that the original issue that prompted the inclusion of `#[allow(unused_qualifications)]` (#19102) is no longer present in the current stable release, and the associated [test case](https://github.com/rust-lang/rust/blob/master/src/test/ui/issues/issue-19102.rs) still passes, so the `allow` is simply removed here.
Rollup merge of #99436 - Nilstrieb:toggle-box-noalias, r=fee1-dead
Add flag to configure `noalias` on `Box<T>`
The aliasing rules of `Box<T>` are still not decided, but currently, `Box<T>` is unique and gets `noalias`. To aid making an informed decision about the future of `Box<T>`, this PR adds a flag `-Zbox-noalias` to configure `noalias` for `Box<T>` (for example, for benchmarking). The same flag already exists for `&mut T` `noalias`, where it was added because it was the problem of various miscompilations in LLVM.
For more information, see rust-lang/unsafe-code-guidelines#326
Rollup merge of #99383 - ouz-a:issue_57961, r=oli-obk
Formalize defining_use_anchor
This tackles issue #57961
Introduces new enum called `DefiningAnchor` that replaces `Option<LocalDefId>` of `defining_use_anchor`. Now every use of it is explicit and exhaustively matched, catching errors like one in the linked issue. This is not a perfect fix but it's a step in the right direction.
Rollup merge of #99345 - compiler-errors:issue-99073-redux, r=oli-obk
Do not allow typeck children items to constrain outer RPITs
Fixes #99073 in a simpler and more conservative way than #99079. Simply raise a mismatched types error if we try to constrain an RPIT in an item that isn't the RPIT's parent.
David Wood [Wed, 13 Jul 2022 09:36:12 +0000 (10:36 +0100)]
attr: fix expected meta-item for `#[stable]`
When an unexpected meta item is provided to `#[stable]`, the diagnostic
lists "since" and "note" as expected meta-items, however the surrounding
code actually expects "feature" and "since".
Auto merge of #99493 - Dylan-DPC:rollup-lli4gcx, r=Dylan-DPC
Rollup of 5 pull requests
Successful merges:
- #98784 (Suggest returning local on "expected `ty`, found `()`" due to expr-less block)
- #98916 (Windows: Use `FindFirstFileW` for getting the metadata of locked system files)
- #99433 (Erase regions before comparing signatures of foreign fns.)
- #99452 (int_macros was only using to_xe_bytes_doc and not from_xe_bytes_doc)
- #99481 (Add regression test for #71547)
Rollup merge of #98916 - ChrisDenton:hiberfil.sys, r=thomcc
Windows: Use `FindFirstFileW` for getting the metadata of locked system files
Fixes #96980
Usually opening a file handle with access set to metadata only will always succeed, even if the file is locked. However some special system files, such as `C:\hiberfil.sys`, are locked by the system in a way that denies even that. So as a fallback we try reading the cached metadata from the directory.
Note that the test is a bit iffy. I don't know if `hiberfil.sys` actually exists in the CI.
Rollup merge of #98784 - compiler-errors:forgot-to-return-binding, r=estebank
Suggest returning local on "expected `ty`, found `()`" due to expr-less block
Putting this up for _initial_ review. Notably, this doesn't consider if the value has possibly been moved, or whether the type is `Copy`. It also provides a structured suggestion if there's one "preferred" binding that matches the type (i.e. one binding in the block or its parent), otherwise it just points them out if there's fewer than 4 of them.
Auto merge of #98843 - Urgau:check-cfg-stage0, r=Mark-Simulacrum
Enable check-cfg in stage0
Now that the bootstrap cargo supports `rustc-check-cfg` we can now enable it with `-Zcheck-cfg=output` and use it in `rustc_llvm` to unblock `--check-cfg` support in stage0.
Auto merge of #99484 - ehuss:update-cargo, r=ehuss
Update cargo
9 commits in 8827baaa781b37872134c1ba692a6f0aeb37890e..d8d30a75376f78bb0fabe3d28ee9d87aa8035309
2022-07-14 02:56:51 +0000 to 2022-07-19 13:59:17 +0000
- docs: fixing minor error in the default timing report filename (rust-lang/cargo#10879)
- Stabilize `--crate-type` flag for `cargo rustc` (rust-lang/cargo#10838)
- Stabilize `-Zmultitarget` (rust-lang/cargo#10766)
- Clean up leftover in unstable documentation (rust-lang/cargo#10874)
- Normalize path for `cargo vendor` output (rust-lang/cargo#10668)
- add a reason to `masquerade_as_nightly_cargo` so it is searchable (rust-lang/cargo#10868)
- Allow '.' in workspace.default-members in non-virtual workspaces. (rust-lang/cargo#10784)
- remove`.masquerade_as_nightly_cargo()` from various tests the no longer need it (rust-lang/cargo#10867)
- remove `.masquerade_as_nightly_cargo()` from build_script_extra_link_arg.rs (rust-lang/cargo#10866)
Auto merge of #98180 - notriddle:notriddle/rustdoc-fn, r=petrochenkov,GuillaumeGomez
Improve the function pointer docs
This is #97842 but for function pointers instead of tuples. The concept is basically the same.
* Reduce duplicate impls; show `fn (T₁, T₂, …, Tₙ)` and include a sentence saying that there exists up to twelve of them.
* Show `Copy` and `Clone`.
* Show auto traits like `Send` and `Sync`, and blanket impls like `Any`.
Michael Howell [Thu, 16 Jun 2022 21:14:38 +0000 (14:14 -0700)]
Improve the function pointer docs
* Reduce duplicate impls; show only the `fn (T)` and include a sentence
saying that there exists up to twelve of them.
* Show `Copy` and `Clone`.
* Show auto traits like `Send` and `Sync`, and blanket impls like `Any`.
Rollup merge of #99457 - SparrowLii:para_iter, r=fee1-dead
use `par_for_each_in` in `par_body_owners` and `collect_crate_mono_items`
Using `par_iter` in non-parallel mode will cause the entire process to abort when any iteration panics. So we can use `par_for_each_in` instead to make the error message consistent with parallel mode. This means that the compiler will output more error messages in some cases. This fixes the following ui tests when set `parallel-compiler = true`:
```
[ui] src/test\ui\privacy\privacy2.rs
[ui] src/test\ui\privacy\privacy3.rs
[ui] src/test\ui\type_length_limit.rs
```
Rollup merge of #99438 - WaffleLapkin:dont_wrap_in_non_zero, r=compiler-errors
Improve suggestions for `NonZeroT` <- `T` coercion error
Currently, when encountering a type mismatch error with `NonZeroT` and `T` (for example `NonZeroU8` and `u8`) we errorneusly suggest wrapping expression in `NonZeroT`:
```text
error[E0308]: mismatched types
--> ./t.rs:7:35
|
7 | let _: std::num::NonZeroU64 = 1;
| -------------------- ^ expected struct `NonZeroU64`, found integer
| |
| expected due to this
|
help: try wrapping the expression in `std::num::NonZeroU64`
|
7 | let _: std::num::NonZeroU64 = std::num::NonZeroU64(1);
| +++++++++++++++++++++ +
```
I've removed this suggestion and added suggestions to call `new` (for `Option<NonZeroT>` <- `T` case) or `new` and `unwrap` (for `NonZeroT` <- `T` case):
```text
error[E0308]: mismatched types
--> ./t.rs:7:35
|
7 | let _: std::num::NonZeroU64 = 1;
| -------------------- ^ expected struct `NonZeroU64`, found integer
| |
| expected due to this
|
help: Consider calling `NonZeroU64::new`
|
7 | let _: std::num::NonZeroU64 = NonZeroU64::new(1).unwrap();
| ++++++++++++++++ ++++++++++
error[E0308]: mismatched types
--> ./t.rs:8:43
|
8 | let _: Option<std::num::NonZeroU64> = 1;
| ---------------------------- ^ expected enum `Option`, found integer
| |
| expected due to this
|
= note: expected enum `Option<NonZeroU64>`
found type `{integer}`
help: Consider calling `NonZeroU64::new`
|
8 | let _: Option<std::num::NonZeroU64> = NonZeroU64::new(1);
| ++++++++++++++++ +
```
https://github.com/rust-lang/rust/issues/99035; the behavior of `$$crate` is potentially unexpected and not ready to be stabilized. https://github.com/rust-lang/rust/pull/99193 attempts to forbid `$$crate` without also destabilizing `$$` more generally.
Rollup merge of #99419 - yoshuawuyts:stabilize-task-ready, r=Mark-Simulacrum
Stabilize `core::task::ready!`
This stabilizes `core::task::ready!` for Rust 1.64. The FCP for stabilization was just completed here https://github.com/rust-lang/rust/issues/70922#issuecomment-1186231855. Thanks!
Rollup merge of #99384 - compiler-errors:issue-99375, r=oli-obk
use body's param-env when checking if type needs drop
The type comes from the body, so we should be using the body's param-env, as opposed to the ADT's param env, because we know less in the latter compared to the former.
I think this should be good to go, there are only two things where I am somewhat unsure:
- Is there a better way to get the fully-qualified path for the suggestion? I tried `self.tcx.def_path_str`, but that didn't seem to always give a correct path for the context.
- Should all this be extracted into it's own method or is it fine where it is?
Rollup merge of #99434 - timvermeulen:skip_next_non_fused, r=scottmcm
Fix `Skip::next` for non-fused inner iterators
`iter.skip(n).next()` will currently call `nth` and `next` in succession on `iter`, without checking whether `nth` exhausts the iterator. Using `?` to propagate a `None` value returned by `nth` avoids this.
Rollup merge of #99335 - Dav1dde:fromstr-docs, r=JohnTitor
Use split_once in FromStr docs
Current implementation:
```rust
fn from_str(s: &str) -> Result<Self, Self::Err> {
let coords: Vec<&str> = s.trim_matches(|p| p == '(' || p == ')' )
.split(',')
.collect();
let x_fromstr = coords[0].parse::<i32>()?;
let y_fromstr = coords[1].parse::<i32>()?;
Ok(Point { x: x_fromstr, y: y_fromstr })
}
```
Creating the vector is not necessary, `split_once` does the job better.
Alternatively we could also remove `trim_matches` with `strip_prefix` and `strip_suffix`:
```rust
let (x, y) = s
.strip_prefix('(')
.and_then(|s| s.strip_suffix(')'))
.and_then(|s| s.split_once(','))
.unwrap();
```
The question is how much 'correctness' is too much and distracts from the example. In a real implementation you would also not unwrap (or originally access the vector without bounds checks), but implementing a custom Error and adding a `From<ParseIntError>` and implementing the `Error` trait adds a lot of code to the example which is not relevant to the `FromStr` trait.
Rollup merge of #97183 - oli-obk:tait_ice_async, r=jackh726
wf-check generators
fixes #90409
We should not rely on generators being well formed by construction now that they can get used via type alias impl trait (and thus users can choose generic arguments that are invalid). This can cause surprising behaviour if (definitely unsound) transmutes are used, and it's generally saner to just check for well formedness.
Auto merge of #98189 - mystor:fast_ident_literal, r=eddyb
proc_macro/bridge: stop using a remote object handle for proc_macro Ident and Literal
This is the fourth part of https://github.com/rust-lang/rust/pull/86822, split off as requested in https://github.com/rust-lang/rust/pull/86822#pullrequestreview-1008655452. This patch transforms the `Ident` and `Group` types into structs serialized over IPC rather than handles.
Symbol values are interned on both the client and server when deserializing, to avoid unnecessary string copies and keep the size of `TokenTree` down. To do the interning efficiently on the client, the proc-macro crate is given a vendored version of the fxhash hasher, as `SipHash` appeared to cause performance issues. This was done rather than depending on `rustc_hash` as it is unfortunately difficult to depend on crates from within `proc_macro` due to it being built at the same time as `std`.
In addition, a custom arena allocator and symbol store was also added, inspired by those in `rustc_arena` and `rustc_span`. To prevent symbol re-use across multiple invocations of a macro on the same thread, a new range of `Symbol` names are used for each invocation of the macro, and symbols from previous invocations are cleaned-up.
In order to keep `Ident` creation efficient, a special ASCII-only case was added to perform ident validation without using RPC for simple identifiers. Full identifier validation couldn't be easily added, as it would require depending on the `rustc_lexer` and `unicode-normalization` crates from within `proc_macro`. Unicode identifiers are validated and normalized using RPC.
See the individual commit messages for more details on trade-offs and design decisions behind these patches.
Don't add attribute to allow unused-qualifications to derive impl's
Currently `#![forbid(unused_qualifications)]` is incompatible with all
derive's because we add `#[allow(unused_qualifications)]` in all
generated impl's.
- Use `expr.hir_id.owner` instead of `self.tcx.parent_module(expr.hir_id)`
- Use `.type_at()` instead of `.first()` + `.expect_ty()`
- Use single `.find()` with `&&` condition
Auto merge of #99422 - Dylan-DPC:rollup-htjofm6, r=Dylan-DPC
Rollup of 7 pull requests
Successful merges:
- #98839 (Add assertion that `transmute_copy`'s U is not larger than T)
- #98998 (Remove branch target prologues from `#[naked] fn`)
- #99198 (add missing null ptr check in alloc example)
- #99344 (rustdoc: avoid inlining items with duplicate `(type, name)`)
- #99351 (Use `typeck_results` to get accurate qpath res for arg mismatch error)
- #99378 (interpret/visitor: add missing early return)
- #99394 (Add regression test for #95230)