Optimize TLS on Windows
This implements the suggestion in the current TLS code to embed the linked list of destructors in the `StaticKey` structure to save allocations. Additionally, locking is avoided when no destructor needs to be run. By using one Windows-provided `Once` per key instead of a global lock, locking is more finely-grained (this unblocks #100579).
rustdoc: merge separate `.item-info` CSS
Rough timeline:
* The longer `.content .item-info` selector originated in 110e7270ab. No reason seems to be given in the PR why it needed the `.content` part, but it was probably added because of <110e7270ab/src/librustdoc/html/static/rustdoc.css (L476-L478)>. That selector with the margin-bottom was removed when CSS containment was added in 8846c0853d.
* `.stability` was renamed `.item-info` in caf6c5790a.
* The selector without the `.content` was added in d48a39a5e2.
tidy: error if a lang feature is already present
If a lang feature gets declared twice, like for example as a result of a mistake during stabilization, emit an error in tidy. Library features already have this logic.
Inspired by a mistake done during `half_open_range_patterns` stabilization: https://github.com/rust-lang/rust/pull/102275/files#r991292215
The PR requires #102883 to be merged before CI turns green because the check is doing its job.
For reviewers, I suggest [turning off whitespace changes](https://github.com/rust-lang/rust/pull/102971/files?w=1) in the diff by adding `?w=1` to the url, as a large part of the diff is just about removing one level of indentation.
Support casting boxes to dyn*
Boxes have a pointer type at codegen time which LLVM does not allow to be transparently converted to an integer. Work around this by inserting a `ptrtoint` instruction if the argument is a pointer.
r? ``@compiler-errors``
Fixes#102427
Allow compiling the `wasm32-wasi` std library with atomics
The issue #102157 demonstrates how currently the `-Z build-std` option will fail when re-compiling the standard library with `RUSTFLAGS` like `RUSTFLAGS="-C target-feature=+atomics,+bulk-memory -C link-args=--shared-memory"`. This change attempts to resolve those build issues by depending on the the WebAssembly `futex` module and providing an implementation for `env_lock`. Fixes#102157.
If a lang feature gets declared twice, like for example as
a result of a mistake during stabilization, emit an error
in tidy. Library features already have this logic.
Support default-body trait functions with return-position `impl Trait` in traits
Introduce a new `Trait` candidate kind for the `ImplTraitInTrait` projection candidate, which just projects an RPITIT down to its opaque type form.
This is a hack until we lower RPITITs to regular associated types, after which we will need to rework how these default bodies are type-checked, so comments are left in a few places for us to clean up later.
Fixes#101665
Rough timeline:
* The longer `.content .item-info` selector originated in
110e7270ab. No reason seems to be given in
the PR why it needed the `.content` part, but it was probably added because
of <110e7270ab/src/librustdoc/html/static/rustdoc.css (L476-L478)>.
That selector with the margin-bottom was removed when CSS containment
was added in 8846c0853d.
* `.stability` was renamed `.item-info` in
caf6c5790a.
* The selector without the `.content` was added in
d48a39a5e2.
Update books
## nomicon
1 commits in f53bfa056929217870a5d2df1366d2e7ba35096d..9c73283775466d22208a0b28afcab44db4c0cc10
2022-09-05 07:19:02 -0700 to 2022-09-30 07:31:22 +0900
- Fix typo (rust-lang/nomicon#380)
## reference
9 commits in a7cdac33ca7356ad49d5c2b5e2c5010889b33eee..f6ed74f582bddcec73f753eafaab3749c4f7df61
2022-09-19 17:39:58 -0700 to 2022-10-08 02:43:26 -0700
- Typo 'a' -> 'an' (rust-lang/reference#1280)
- One line one sentence for expressions and statements main chapters (rust-lang/reference#1277)
- Document let else statements (rust-lang/reference#1156)
- Document `label_break_value` in the reference (rust-lang/reference#1263)
- Document target_has_atomic (rust-lang/reference#1171)
- update 'unsafe' (rust-lang/reference#1278)
- Update tokens.md (rust-lang/reference#1276)
- One sentence, one line Patterns chapter (rust-lang/reference#1275)
- Use semver-compliant example version (rust-lang/reference#1272)
## rust-by-example
9 commits in 767a6bd9727a596d7cfdbaeee475e65b2670ea3a..5e7b296d6c345addbd748f242aae28c42555c015
2022-09-14 09:17:18 -0300 to 2022-10-05 08:24:45 -0300
- Make it clear that rustdoc uses the commonmark spec (rust-lang/rust-by-example#1622)
- Update defaults.md (rust-lang/rust-by-example#1615)
- added "see also" for the @ binding sigil (rust-lang/rust-by-example#1612)
- add more precision to the effects of --bin flag (rust-lang/rust-by-example#1607)
- create bar project in cargo/dependencies example (rust-lang/rust-by-example#1606)
- use consistent wording about type annotation (rust-lang/rust-by-example#1603)
- cast.md improvements (rust-lang/rust-by-example#1599)
- Fix typo in macros.md (rust-lang/rust-by-example#1598)
- Corrected mistaken "The" instead of "There" (rust-lang/rust-by-example#1617)
## rustc-dev-guide
2 commits in 9a86c0467bbe42056f73fdf5b03fff757d7c4a9b..7518c3445dc02df0d196f5f84e568d633c5141fb
2022-10-07 18:34:51 +0200 to 2022-10-08 12:29:47 +0200
- Update debugging.md
- Use llvm subdomain for compiler-explorer link
## embedded-book
1 commits in 4ce51cb7441a6f02b5bf9b07b2eb755c21ab7954..c533348edd69f11a8f4225d633a05d7093fddbf3
2022-09-15 08:53:09 +0000 to 2022-10-10 10:16:49 +0000
- Fix a typo in registers.md (rust-embedded/book#330)
Fix `let` keyword removal suggestion in structs
(1.) Fixes a bug where, given this code:
```rust
struct Foo {
let x: i32,
}
```
We were parsing the field name as `let` instead of `x`, which causes issues later on in the type-checking phase.
(2.) Also, suggestions for `let: i32` as a field regressed, displaying this extra `help:` which is removed by this PR
```
help: remove the let, the `let` keyword is not allowed in struct field definitions
|
2 - let: i32,
2 + : i32,
```
(3.) Makes the suggestion text a bit more succinct, since we don't need to re-explain that `let` is not allowed in this position (since it's in a note that follows). This causes the suggestion to render inline as well.
cc `@gimbles,` this addresses a few nits I mentioned in your PR.
Unify `tcx.constness` query and param env constness checks
The checks that we do in the `constness` query seem inconsistent with the checks that we do to determine if an item's param-env is const, so I merged them into the `constness` query and call that from the `param_env` query.
I'm not sure if this totally makes sense -- is there a case where `tcx.param_env()` would return a const param-env for an item whose `tcx.constness()` is `Constness::NotConst`? Because if not, it seems a bit dangerous that these two differ.
Luckily, not many places actually use `tcx.constness()`, and the checks in `tcx.param_env()` seem stricter than the checks in `tcx.constness()` (at least for the types of items we type-check).
Also, due to the way that `tcx.param_env()` is implemented, it _never_ used to return a const param-env for a item coming from a different crate, which also seems dangerous (though also probably not weaponizable currently, because we seldom actually compute the param-env for a non-local item).
Enforce alphabetical sorting with tidy
We have many places where things are supposed to be sorted alphabetically. For the smaller and more recent size assertions, this is mostly upheld, but in other more... alive places it's very messy.
This introduces a new tidy directive to check that a section of code is sorted alphabetically and fixes all places where sorting has gone wrong.
translation: eager translation
Part of #100717. See [Zulip thread](https://rust-lang.zulipchat.com/#narrow/stream/336883-i18n/topic/.23100717.20lists!/near/295010720) for additional context.
- **Store diagnostic arguments in a `HashMap`**: Eager translation will enable subdiagnostics to be translated multiple times with different arguments - this requires the ability to replace the value of one argument with a new value, which is better suited to a `HashMap` than the previous storage, a `Vec`.
- **Add `AddToDiagnostic::add_to_diagnostic_with`**: `AddToDiagnostic::add_to_diagnostic_with` is similar to the previous `AddToDiagnostic::add_to_diagnostic` but takes a function that can be used by the caller to modify diagnostic messages originating from the subdiagnostic (such as performing translation eagerly). `add_to_diagnostic` now just calls `add_to_diagnostic_with` with an empty closure.
- **Add `DiagnosticMessage::Eager`**: Add variant of `DiagnosticMessage` for eagerly translated messages
(messages in the target language which don't need translated by the emitter during emission). Also adds `eager_subdiagnostic` function which is intended to be invoked by the diagnostic derive for subdiagnostic fields which are marked as needing eager translation.
- **Support `#[subdiagnostic(eager)]`**: Add support for `eager` argument to the `subdiagnostic` attribute which generates a call to `eager_subdiagnostic`.
- **Finish migrating `rustc_query_system`**: Using eager translation, migrate the remaining repeated cycle stack diagnostic.
- **Split formatting initialization and use in diagnostic derives**: Diagnostic derives have previously had to take special care when ordering the generated code so that fields were not used after a move.
This is unlikely for most fields because a field is either annotated with a subdiagnostic attribute and is thus likely a `Span` and copiable, or is a argument, in which case it is only used once by `set_arg`
anyway.
However, format strings for code in suggestions can result in fields being used after being moved if not ordered carefully. As a result, the derive currently puts `set_arg` calls last (just before emission), such as:
let diag = { /* create diagnostic */ };
diag.span_suggestion_with_style(
span,
fluent::crate::slug,
format!("{}", __binding_0),
Applicability::Unknown,
SuggestionStyle::ShowAlways
);
/* + other subdiagnostic additions */
diag.set_arg("foo", __binding_0);
/* + other `set_arg` calls */
diag.emit();
For eager translation, this doesn't work, as the message being translated eagerly can assume that all arguments are available - so arguments _must_ be set first.
Format strings for suggestion code are now separated into two parts - an initialization line that performs the formatting into a variable, and a usage in the subdiagnostic addition.
By separating these parts, the initialization can happen before arguments are set, preserving the desired order so that code compiles, while still enabling arguments to be set before subdiagnostics are added.
let diag = { /* create diagnostic */ };
let __code_0 = format!("{}", __binding_0);
/* + other formatting */
diag.set_arg("foo", __binding_0);
/* + other `set_arg` calls */
diag.span_suggestion_with_style(
span,
fluent::crate::slug,
__code_0,
Applicability::Unknown,
SuggestionStyle::ShowAlways
);
/* + other subdiagnostic additions */
diag.emit();
- **Remove field ordering logic in diagnostic derive:** Following the approach taken in earlier commits to separate formatting initialization from use in the subdiagnostic derive, simplify the diagnostic derive by removing the field-ordering logic that previously solved this problem.
r? ```@compiler-errors```
nicer errors from assert_unsafe_precondition
This makes the errors shown by cargo-careful nicer, and since `panic_no_unwind` is `nounwind noreturn` it hopefully doesn't have bad codegen impact. Thanks to `@bjorn3` for the hint!
Would be nice if we could somehow supply our own (static) message to print, currently it always prints `panic in a function that cannot unwind`. But still, this is better than before.
It can be used to ensure that a list of things is sorted alphabetically.
It goes off lines, but contains several heuristics to work with normal
Rust code (looking at indentation, ignoring comments and attributes).
Prevent UB in child process after calling libc::fork
After calling libc::fork, the child process tried to access a TLS variable when processing a panic. This caused a memory allocation which is UB in the child.
To prevent this from happening, the panic handler will not access the TLS variable in case `panic::always_abort` was called before.
Fixes#85261 (not only on Android systems, but also on Linux/QNX with TLS disabled, see issue for more details)
Main drawbacks of this fix:
* Panic messages can incorrectly omit `core::panic::PanicInfo` struct in case several panics (of multiple threads) occur at the same time. The handler cannot distinguish between multiple panics in different threads or recursive ones in the same thread, but the message will contain a hint about the uncertainty.
* `panic_count::increase()` will be a bit slower as it has an additional `if`, but this should be irrelevant as it is only called in case of a panic.
