android: Remove libstd hacks for unsupported Android APIs
Our minimum supported API version is 21, remove hacks to support older Android APIs.
try-job: arm-android
r? tgross35
Rollup of 7 pull requests
Successful merges:
- #123813 (Add `REDUNDANT_IMPORTS` lint for new redundant import detection)
- #126697 ([RFC] mbe: consider the `_` in 2024 an expression)
- #127159 (match lowering: Hide `Candidate` from outside the lowering algorithm)
- #128244 (Peel off explicit (or implicit) deref before suggesting clone on move error in borrowck, remove some hacks)
- #128431 (Add myself as VxWorks target maintainer for reference)
- #128438 (Add special-case for [T, 0] in dropck_outlives)
- #128457 (Fix docs for OnceLock::get_mut_or_init)
r? `@ghost`
`@rustbot` modify labels: rollup
Cleanup sys module to match house style
This moves a test file out of sys as it's just testing std types. Also cleans up some assorted bits including making the `use` statements match the house style.
std: implement the `once_wait` feature
Tracking issue: #127527
This additionally adds a `wait_force` method to `Once` that doesn't panic on poison.
I also took the opportunity and cleaned up up the code of the queue-based implementation a bit.
Match LLVM ABI in `extern "C"` functions for `f128` on Windows
As MSVC doesn't support `_Float128`, x86-64 Windows doesn't have a defined ABI for `f128`. Currently, Rust will pass and return `f128` indirectly for `extern "C"` functions. This is inconsistent with LLVM, which passes and returns `f128` in XMM registers, meaning that e.g. the ABI of `extern "C"` compiler builtins won't match. This PR fixes this discrepancy by making the x86-64 Windows `extern "C"` ABI pass `f128` directly through to LLVM, so that Rust will follow whatever LLVM does. This still leaves the difference between LLVM and GCC (https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115054) but this PR is still an improvement as at least Rust is now consistent with it's primary codegen backend and compiler builtins from `compiler-builtins` will now work.
I've also fixed the x86-64 Windows `has_reliable_f16` match arm in `std` `build.rs` to refer to the correct target, and added an equivalent match arm to `has_reliable_f128` as the LLVM-GCC ABI difference affects both `f16` and `f128`.
Tracking issue: #116909
try-job: x86_64-msvc
try-job: x86_64-mingw
Clean and enable `rustdoc::unescaped_backticks` for `core/alloc/std/test/proc_macro`
I am not sure if the lint is supposed to be "ready enough" (since it is `allow` by default), but it does catch a couple issues in `core` (`alloc`, `std`, `test` and `proc_macro` are already clean), so I propose making it `warn` in all the crates rendered in the website.
Cc: `@GuillaumeGomez`
Update compiler_builtins to 0.1.114
The `weak-intrinsics` feature was removed from compiler_builtins in https://github.com/rust-lang/compiler-builtins/pull/598, so dropped the `compiler-builtins-weak-intrinsics` feature from alloc/std/sysroot.
In https://github.com/rust-lang/compiler-builtins/pull/593, some builtins for f16/f128 were added. These don't work for all compiler backends, so add a `compiler-builtins-no-f16-f128` feature and disable it for cranelift and gcc.
std: unsafe-wrap personality::dwarf::eh
Moves the forbiddance up a little. This is another largely whitespace diff, except for hoisting some variable declarations to allow enclosing the `unsafe {}` scope fully and make it clearer where the bounds of some temporaries are.
Replace `io::Cursor::{remaining_slice, is_empty}`
This is a late follow up to the concerns raised in https://github.com/rust-lang/rust/issues/86369.
https://github.com/rust-lang/rust/issues/86369#issuecomment-953096691
> This API seems focussed on the `Read` side of things. When `Seek`ing around and `Write`ing data, `is_empty` becomes confusing and `remaining_slice` is not very useful. When writing, the part of the slice before the cursor is much more interesting. Maybe we should have functions for both? Or a single function that returns both slices? (If we also have a `mut` version, a single function would be useful to allow mutable access to both sides at once.)
New feature name: `cursor_remaining` > `cursor_split`.
Added functions:
```rust
fn split(&self) -> (&[u8], &[u8]);
// fn before(&self) -> &[u8];
// fn after(&self) -> &[u8];
fn split_mut(&mut self) -> (&mut [u8], &mut [u8]);
// fn before_mut(&mut self) -> &mut [u8];
// fn after_mut(&mut self) -> &mut [u8];
```
A question was raised in https://github.com/rust-lang/rust/issues/86369#issuecomment-927124211 about whether to return a lifetime that would reflect the lifetime of the underlying bytes (`impl Cursor<&'a [u8]> { fn after(&self) -> &'a [u8] }`). The downside of doing this would be that it would not be possible to implement these functions generically over `T: AsRef<[u8]>`.
## Update
Based on the review, before* and after* methods where removed.
The `weak-intrinsics` feature was removed from compiler_builtins in
https://github.com/rust-lang/compiler-builtins/pull/598, so dropped the
`compiler-builtins-weak-intrinsics` feature from alloc/std/sysroot.
In https://github.com/rust-lang/compiler-builtins/pull/593, some
builtins for f16/f128 were added. These don't work for all compiler
backends, so add a `compiler-builtins-no-f16-f128` feature and disable
it for cranelift and gcc. Also disable it for LLVM targets that don't
support it.
Stabilize `const_waker`
Closes: https://github.com/rust-lang/rust/issues/102012.
For `local_waker` and `context_ext` related things, I just ~~moved them to dedicated feature gates and reused their own tracking issue (maybe it's better to open a new one later, but at least they should not be tracked under https://github.com/rust-lang/rust/issues/102012 from the beginning IMO.)~~ reused their own feature gates as suggested by ``@tgross35.``
``@rustbot`` label: +T-libs-api
r? libs-api
Fix doc nits
Many tiny changes to stdlib doc comments to make them consistent (for example "Returns foo", rather than "Return foo"), adding missing periods, paragraph breaks, backticks for monospace style, and other minor nits.
Both these platforms have MSG_NOSIGNAL available, and we should set it for
socket writes in the event that the SIGPIPE handler has been reset to SIG_DFL
(i.e. terminate the process).
I've verified via a quick program at
https://github.com/sunshowers/msg-nosignal-test/ that even when the SIGPIPE
handler is reset to SIG_DFL, writes to closed sockets now error out with EPIPE.
(Under ordinary circumstances UDP writes won't cause MSG_NOSIGNAL.)
Use `#[rustfmt::skip]` on some `use` groups to prevent reordering.
`use` declarations will be reformatted in #125443. Very rarely, there is a desire to force a group of `use` declarations together in a way that auto-formatting will break up. E.g. when you want a single comment to apply to a group. #126776 dealt with all of these in the codebase, ensuring that no comments intended for multiple `use` declarations would end up in the wrong place. But some people were unhappy with it.
This commit uses `#[rustfmt::skip]` to create these custom `use` groups in an idiomatic way for a few of the cases changed in #126776. This works because rustfmt treats any `use` item annotated with `#[rustfmt::skip]` as a barrier and won't reorder other `use` items around it.
r? `@cuviper`
Rollup of 6 pull requests
Successful merges:
- #126908 (Use Cow<'static, str> for InlineAsmTemplatePiece::String)
- #127999 (Inject arm32 shims into Windows metadata generation)
- #128137 (CStr: derive PartialEq, Eq; add test for Ord)
- #128185 (Fix a span error when parsing a wrong param of function.)
- #128187 (Fix 1.80.0 version in RELEASES.md)
- #128189 (Turn an unreachable code path into an ICE)
r? `@ghost`
`@rustbot` modify labels: rollup
Inject arm32 shims into Windows metadata generation
I had been keen to eventually move to using windows-sys as a normal Cargo dependency. But for linking, compile times and other reasons that's unlikely to ever happen.
So if we're sticking with generated bindings then injecting any necessary missing type definitions (i.e. for the MS unsupported arm32) is simpler than defining whole functions ourselves just because we need to manually implement those types on a tier 3 platform. This also reduces the places we need to change when making changes to how we use `#[link]`.
r? libs
std: unsafe-wrap personality::gcc
Nothing seems obviously wrong with these implementations except for some unanswered questions. Admittedly, I don't want to burn excessive time on exceptional exception handlers. Thus this is mostly a brute-force syntactic wrapping and some comments where they seemed correct, creating another largely whitespace diff.
try-job: armhf-gnu
Fix connect timeout for non-linux targets, read readiness of socket connection, Read readiness to detect errors. `Fixes #127018`
Fixes#127018
Connect_timeout would call `poll` and check `pollfd.revents` for POLLHUP error, rather that checking readiness. This behavior was meant for Linux as it returns POLLHUP | POLLOUT | POLLERR in case of errors. But on targets that do not return POLLHUP in `pollfd.revents`, this would indicate a false success and result in this issue. To resolve this we will check readiness of socket using `getsockopt():` and return success from connect_timeout when there are no errors.
Changes were tested on Linux and an rtos.
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Thank you.
Import `c_void` rather than using the full path
Follow up to #128092. As requested, this imports `c_void` in more places. I also fixed up some imports to use `core` for core types instead of `crate`. While that is not strictly necessary, I think ideally things in `sys/pal` should only depend on itself or core so that the code is less spaghetti. We're far away from that ideal at the moment but I can at least try to slowly move in that direction.
Also this forbids `unsafe_op_in_unsafe_fn` for library/std/src/sys/pal/windows by fixing up the remaining unsafe bits that are just punting their unsafe requirements onto the caller of the `unsafe` function (or definition macro).
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