This new documentation tries to avoid to limit the impact of the
conceptual pitfall, that the if guard relaxes the constraint, when
really it tightens it. This is achieved by changing the text and
examples. The previous documentation also chose a rather weird and
non-representative example for the if guard, that made it needlessly
complicated to understand.
Add a new `wasm32-wasi-preview2` target
This is the initial implementation of the MCP https://github.com/rust-lang/compiler-team/issues/694 creating a new tier 3 target `wasm32-wasi-preview2`. That MCP has been seconded and will most likely be approved in a little over a week from now. For more information on the need for this target, please read the [MCP](https://github.com/rust-lang/compiler-team/issues/694).
There is one aspect of this PR that will become insta-stable once these changes reach a stable compiler:
* A new `target_family` named `wasi` is introduced. This target family incorporates all wasi targets including `wasm32-wasi` and its derivative `wasm32-wasi-preview1-threads`. The difference between `target_family = wasi` and `target_os = wasi` will become much clearer when `wasm32-wasi` is renamed to `wasm32-wasi-preview1` and the `target_os` becomes `wasm32-wasi-preview1`. You can read about this target rename in [this MCP](https://github.com/rust-lang/compiler-team/issues/695) which has also been seconded and will hopefully be officially approved soon.
Additional technical details include:
* Both `std::sys::wasi_preview2` and `std::os::wasi_preview2` have been created and mostly use `#[path]` annotations on their submodules to reach into the existing `wasi` (soon to be `wasi_preview1`) modules. Over time the differences between `wasi_preview1` and `wasi_preview2` will grow and most like all `#[path]` based module aliases will fall away.
* Building `wasi-preview2` relies on a [`wasi-sdk`](https://github.com/WebAssembly/wasi-sdk) in the same way that `wasi-preview1` does (one must include a `wasi-root` path in the `Config.toml` pointing to sysroot included in the wasi-sdk). The target should build against [wasi-sdk v21](https://github.com/WebAssembly/wasi-sdk/releases/tag/wasi-sdk-21) without modifications. However, the wasi-sdk itself is growing [preview2 support](https://github.com/WebAssembly/wasi-sdk/pull/370) so this might shift rapidly. We will be following along quickly to make sure that building the target remains possible as the wasi-sdk changes.
* This requires a [patch to libc](https://github.com/rylev/rust-libc/tree/wasm32-wasi-preview2) that we'll need to land in conjunction with this change. Until that patch lands the target won't actually build.
os::net: expanding TcpStreamExt for Linux with `tcp_deferaccept`.
allows for socket to process only when there is data to process, the option sets a number of seconds until the data is ready.
Update Vec and String `{from,into}_raw_parts`-family docs
- Fix documentation argument order to match the code argument order for consistency.
- Add return argument description for `{Vec,String}::into_raw_parts` to match their `from*` counterparts.
rename 'try' intrinsic to 'catch_unwind'
The intrinsic has nothing to do with `try` blocks, and corresponds to the stable `catch_unwind` function, so this makes a lot more sense IMO.
Also rename Miri's special function while we are at it, to reflect the level of abstraction it works on: it's an unwinding mechanism, on which Rust implements panics.
Always use WaitOnAddress on Win10+
`WaitOnAddress` and `WakeByAddressSingle` are always available since Windows 8 so they can now be used without needing to delay load. I've also moved the Windows 7 thread parking fallbacks into a separate sub-module.
Fix sgx unit test compilation
Fixes a compilation error:
```
error[E0583]: file not found for module `tests`
--> library/std/src/sys/locks/rwlock/sgx.rs:2:1
|
2 | mod tests;
| ^^^^^^^^^^
|
= help: to create the module `tests`, create file "library/std/src/sys/locks/rwlock/sgx/tests.rs" or "library/std/src/sys/locks/rwlock/sgx/tests/mod.rs"
= note: if there is a `mod tests` elsewhere in the crate already, import it with `use crate::...` instead
For more information about this error, try `rustc --explain E0583`.
error: could not compile `std` (lib test) due to 1 previous error`
```
When running command:
```
`TF_BUILD=True RUST_TEST_THREADS=1 ./x.py test --stage 1 "library/std" tests/assembly tests/run-make --target=x86_64-fortanix-unknown-sgx --no-doc --exclude src/tools/linkchecker --exclude src/tools/rust-demangler --no-fail-fast 2>&1
```
The fix is done by moving a file to the location suggested by the compiler.
The issue was introduced by PR: https://github.com/rust-lang/rust/pull/121177
Stabilize `cfg_target_abi`
This stabilizes the `cfg` option called `target_abi`:
```rust
#[cfg(target_abi = "eabihf")]
```
Tracking issue: #80970fixes#78791resolves#80970
Implement `MappedMutexGuard`, `MappedRwLockReadGuard`, and `MappedRwLockWriteGuard`.
ACP: https://github.com/rust-lang/libs-team/issues/260
Tracking issue: https://github.com/rust-lang/rust/issues/117108
<details> <summary> (Outdated) </summary>
`MutexState`/`RwLockState` structs
~~Having `sys::(Mutex|RwLock)` and `poison::Flag` as separate fields in the `Mutex`/`RwLock` would require `MappedMutexGuard`/`MappedRwLockWriteGuard` to hold an additional pointer, so I combined the two fields into a `MutexState`/`RwLockState` struct. This should not noticeably affect perf or layout, but requires an additional field projection when accessing the former `.inner` or `.poison` fields (now `.state.inner` and `.state.poison`).~~ If this is not desired, then `MappedMutexGuard`/`MappedRwLockWriteGuard` can instead hold separate pointers to the two fields.
</details>
The doc-comments are mostly copied from the existing `*Guard` doc-comments, with some parts from `lock_api::Mapped*Guard`'s doc-comments.
Unresolved question: Are more tests needed?
Add `#[rustc_no_mir_inline]` for standard library UB checks
should help with #121110 and also with #120848
Because the MIR inliner cannot know whether the checks are enabled or not, so inlining is an unnecessary compile time pessimization when debug assertions are disabled. LLVM knows whether they are enabled or not, so it can optimize accordingly without wasting time.
r? `@saethlin`
Forbid use of `extern "C-unwind"` inside standard library
Those libraries are build with `-C panic=unwind` and is expected to be linkable to `-C panic=abort` library. To ensure unsoundness compiler needs to prevent a `C-unwind` call to exist, as doing so may leak foreign exceptions into `-C panic=abort`.
r? ``@RalfJung``
Fix incorrect doc of ScopedJoinHandle::is_finished
Fixes the explanation how to use `is_finished` to achieve a non-blocking join. The updated version matches the documentation of the non-scoped JoinHandle::is_finished.
Add examples for some methods on slices
Adds some examples to some methods on slice.
`is_empty` didn't have an example for an empty slice, even though `str` and the collections all have one, so I added that in.
`first_mut` and `last_mut` didn't have an example for what happens when the slice is empty, whereas `first` and `last` do, so I added that too.
Those libraries are build with `-C panic=unwind` and is expected to
be linkable to `-C panic=abort` library. To ensure unsoundness
compiler needs to prevent a `C-unwind` call to exist, as doing so may leak
foreign exceptions into `-C panic=abort`.
Fixes the explanation how to use is_finished to achieve a non-blocking
join. The updated version matches the documentation of the non-scoped
JoinHandle::is_finished.
Make QNX/NTO specific "timespec capping" public to crate::sys
It is used in:
- `library/std/src/sys/locks/condvar/pthread.rs`
- `library/std/src/sys/pal/unix/thread_parking/pthread.rs`
This is probably required due to introduction of `sys/pal` and #121177
`@rustbot` label +O-neutrino
CC: `@jonathanpallant` `@japaric` `@gh-tr`
Provide suggestions through `rustc_confusables` annotations
Help with common API confusion, like asking for `push` when the data structure really has `append`.
```
error[E0599]: no method named `size` found for struct `Vec<{integer}>` in the current scope
--> $DIR/rustc_confusables_std_cases.rs:17:7
|
LL | x.size();
| ^^^^
|
help: you might have meant to use `len`
|
LL | x.len();
| ~~~
help: there is a method with a similar name
|
LL | x.resize();
| ~~~~~~
```
Fix#59450 (we can open subsequent tickets for specific cases).
Fix#108437:
```
error[E0599]: `Option<{integer}>` is not an iterator
--> f101.rs:3:9
|
3 | opt.flat_map(|val| Some(val));
| ^^^^^^^^ `Option<{integer}>` is not an iterator
|
::: /home/gh-estebank/rust/library/core/src/option.rs:571:1
|
571 | pub enum Option<T> {
| ------------------ doesn't satisfy `Option<{integer}>: Iterator`
|
= note: the following trait bounds were not satisfied:
`Option<{integer}>: Iterator`
which is required by `&mut Option<{integer}>: Iterator`
help: you might have meant to use `and_then`
|
3 | opt.and_then(|val| Some(val));
| ~~~~~~~~
```
On type error of method call arguments, look at confusables for suggestion. Fix#87212:
```
error[E0308]: mismatched types
--> f101.rs:8:18
|
8 | stuff.append(Thing);
| ------ ^^^^^ expected `&mut Vec<Thing>`, found `Thing`
| |
| arguments to this method are incorrect
|
= note: expected mutable reference `&mut Vec<Thing>`
found struct `Thing`
note: method defined here
--> /home/gh-estebank/rust/library/alloc/src/vec/mod.rs:2025:12
|
2025 | pub fn append(&mut self, other: &mut Self) {
| ^^^^^^
help: you might have meant to use `push`
|
8 | stuff.push(Thing);
| ~~~~
```
