Stabilize the Rust 2024 prelude
This stabilizes the `core::prelude::rust_2024` and `std::prelude::rust_2024` modules. I missed these in the #133349 stabilization.
Run TLS destructors for wasm32-wasip1-threads
The target wasm32-wasip1-threads has support for pthreads and allows registration of TLS destructors.
For spawned threads, this registers Rust TLS destructors by creating a pthreads key with an attached destructor function.
For the main thread, this registers an `atexit` handler to run the TLS destructors.
try-job: test-various
wasi/fs: Improve stopping condition for <ReadDir as Iterator>::next
When upgrading [Zed](https://github.com/zed-industries/zed/pull/19349) to Rust 1.82 I've encountered a test failure in our test suite. Specifically, one of our extension tests started hanging. I've tracked it down to a call to std::fs::remove_dir_all not returning when an extension is compiled with Rust 1.82 Our extension system uses WASM components, thus I've looked at the diff between 1.81 and 1.82 with respect to WASI and found 736f773844
As it turned out, calling remove_dir_all from extension returned io::ErrorKind::NotFound in 1.81; the underlying issue is that the ReadDir iterator never actually terminates iteration, however since it loops around, with 1.81 we'd come across an entry second time and fail to remove it, since it would've been removed previously. With 1.82 and 736f773844 it is no longer the case, thus we're seeing the hang. The tests do pass when everything but the extensions is compiled with 1.82.
This commit makes ReadDir::next adhere to readdir contract, namely it will no longer call readdir once the returned # of bytes is smaller than the size of a passed-in buffer. Previously we'd only terminate the loop if readdir returned 0.
Define acronym for thread local storage
There are multiple references in this module's documentation to the acronym "TLS" (meaning "thread local storage"), without defining it. This is confusing for the reader.
I propose that this acronym be defined during the first use of the term.
There are multiple references in this module's documentation to the acronym "TLS", without defining it. This is confusing for the reader.
I propose that this acronym be defined during the first use of the term.
Implementation of `fmt::FormattingOptions`
Tracking issue: #118117
Public API:
```rust
#[derive(Copy, Clone, Debug, PartialEq, Eq)]
pub struct FormattingOptions { … }
#[derive(Copy, Clone, Debug, PartialEq, Eq)]
pub enum Sign {
Plus,
Minus
}
#[derive(Copy, Clone, Debug, PartialEq, Eq)]
pub enum DebugAsHex {
Lower,
Upper
}
impl FormattingOptions {
pub fn new() -> Self;
pub fn sign(&mut self, sign: Option<Sign>) -> &mut Self;
pub fn sign_aware_zero_pad(&mut self, sign_aware_zero_pad: bool) -> &mut Self;
pub fn alternate(&mut self, alternate: bool) -> &mut Self;
pub fn fill(&mut self, fill: char) -> &mut Self;
pub fn align(&mut self, alignment: Option<Alignment>) -> &mut Self;
pub fn width(&mut self, width: Option<usize>) -> &mut Self;
pub fn precision(&mut self, precision: Option<usize>) -> &mut Self;
pub fn debug_as_hex(&mut self, debug_as_hex: Option<DebugAsHex>) -> &mut Self;
pub fn get_sign(&self) -> Option<Sign>;
pub fn get_sign_aware_zero_pad(&self) -> bool;
pub fn get_alternate(&self) -> bool;
pub fn get_fill(&self) -> char;
pub fn get_align(&self) -> Option<Alignment>;
pub fn get_width(&self) -> Option<usize>;
pub fn get_precision(&self) -> Option<usize>;
pub fn get_debug_as_hex(&self) -> Option<DebugAsHex>;
pub fn create_formatter<'a>(self, write: &'a mut (dyn Write + 'a)) -> Formatter<'a>;
}
impl<'a> Formatter<'a> {
pub fn new(write: &'a mut (dyn Write + 'a), options: FormattingOptions) -> Self;
pub fn with_options<'b>(&'b mut self, options: FormattingOptions) -> Formatter<'b>;
pub fn sign(&self) -> Option<Sign>;
pub fn options(&self) -> FormattingOptions;
}
```
Relevant changes from the public API in the tracking issue (I'm leaving out some stuff I consider obvious mistakes, like missing `#[derive(..)]`s and `pub` specifiers):
- `enum DebugAsHex`/`FormattingOptions::debug_as_hex`/`FormattingOptions::get_debug_as_hex`: To support `{:x?}` as well as `{:X?}`. I had completely missed these options in the ACP. I'm open for any and all bikeshedding, not married to the name.
- `fill`/`get_fill` now takes/returns `char` instead of `Option<char>`. This simply mirrors what `Formatter::fill` returns (with default being `' '`).
- Changed `zero_pad`/`get_zero_pad` to `sign_aware_zero_pad`/`get_sign_aware_zero_pad`. This also mirrors `Formatter::sign_aware_zero_pad`. While I'm not a fan of this quite verbose name, I do believe that having the interface of `Formatter` and `FormattingOptions` be compatible is more important.
- For the same reason, renamed `alignment`/`get_alignment` to `aling`/`get_align`.
- Deviating from my initial idea, `Formatter::with_options` returns a `Formatter` which has the lifetime of the `self` reference as its generic lifetime parameter (in the original API spec, the generic lifetime of the returned `Formatter` was the generic lifetime used by `self` instead). Otherwise, one could construct two `Formatter`s that both mutably borrow the same underlying buffer, which would be unsound. This solution still has performance benefits over simply using `Formatter::new`, so I believe it is worthwhile to keep this method.
Stabilize `std::io::ErrorKind::CrossesDevices`
FCP in #130191
cc #86442
See #130191 for more info and a recap of what has happened up until now.
TLDR: This had been FCP'd in December 2022 with some other `ErrorKind`s, but the stabilization got postponed due to some concerns voiced about several of the variants. However, the only concern ever voiced for this variant in particular was a wish to rename this to `NotSameDevice` analogous to Windows's `ERROR_NOT_SAME_DEVICE` (as opposed to Unix's `EXDEV`). This suggestion did not receive any support. So let's try to FCP this as is.
r? libs-api
Improve comments for the default backtrace printer
The existing comments were misleading, confusing, and outdated.
Take this comment for example:
```
// Any frames between `__rust_begin_short_backtrace` and `__rust_end_short_backtrace`
// are omitted from the backtrace in short mode, `__rust_end_short_backtrace` will be
// called before the panic hook, so we won't ignore any frames if there is no
// invoke of `__rust_begin_short_backtrace`.
```
this is just wrong. here is an example (full) backtrace:
<details>
```
Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.01s
Running `/home/jyn/.local/lib/cargo/target/debug/example`
called `Option::unwrap()` on a `None` value
stack backtrace:
0: 0x56499698c595 - std::backtrace_rs::backtrace::libunwind::trace::h5ef2cc16e9a7415a
1: 0x56499698c595 - std::backtrace_rs::backtrace::trace_unsynchronized::h9b5e016e9075f714
2: 0x56499698c595 - std::sys_common::backtrace::_print_fmt::h2f62c7f9ff224e93
3: 0x56499698c595 - <std::sys_common::backtrace::_print::DisplayBacktrace as core::fmt::Display>::fmt::hbe51682735731910
4: 0x5649969aa26b - core::fmt::rt::Argument::fmt::h1994ab2b310d665e
5: 0x5649969aa26b - core::fmt::write::hade58a36d63468d7
6: 0x56499698a43f - std::io::Write::write_fmt::h16145587d801a9ab
7: 0x56499698c36e - std::sys_common::backtrace::_print::ha8082e56201dadb4
8: 0x56499698c36e - std::sys_common::backtrace::print::he30f96b4e7f6cbfd
9: 0x56499698d709 - std::panicking::default_hook::{{closure}}::hf0801f6b18a968d3
10: 0x56499698d4ac - std::panicking::default_hook::hd2defec7eda5aeb0
11: 0x56499698dc31 - std::panicking::rust_panic_with_hook::hde93283600065c53
12: 0x56499698daf3 - std::panicking::begin_panic_handler::{{closure}}::h5e151adbdb7ec0c1
13: 0x56499698ca59 - std::sys_common::backtrace::__rust_end_short_backtrace::he36a1407e0f77700
14: 0x56499698d7d4 - rust_begin_unwind
15: 0x5649969a9503 - core::panicking::panic_fmt::h2380d41365f95412
16: 0x5649969a958c - core::panicking::panic::h38cf8db80e8c6e67
17: 0x5649969a93e9 - core::option::unwrap_failed::he72696e53ff29a05
18: 0x5649969722b6 - core::option::Option<T>::unwrap::hb574dc0dc1703062
19: 0x5649969722b6 - example::main::h7a867aafacd93d75
20: 0x5649969721db - core::ops::function::FnOnce::call_once::h734f99a5e57291b7
21: 0x56499697226e - std::sys_common::backtrace::__rust_begin_short_backtrace::h02f5d58c351c4756
22: 0x564996972241 - std::rt::lang_start::{{closure}}::h8b134fe2c31a4355
23: 0x564996988662 - core::ops::function::impls::<impl core::ops::function::FnOnce<A> for &F>::call_once::h88d7bb571ee2aaf4
24: 0x564996988662 - std::panicking::try::do_call::hfb78dfb6599c871d
25: 0x564996988662 - std::panicking::try::habd041c8c4c8e50c
27: 0x564996988662 - std::rt::lang_start_internal::{{closure}}::h227591a6f9c0879e
28: 0x564996988662 - std::panicking::try::do_call::h3c5878333c38916a
29: 0x564996988662 - std::panicking::try::h5af7b3a127cdae70
31: 0x564996988662 - std::rt::lang_start_internal::hbc85e809eeace0dd
32: 0x56499697221a - std::rt::lang_start::ha1eb16922c9cb224
33: 0x5649969722ee - main
34: 0x7f031962a1ca - __libc_start_call_main
35: 0x7f031962a28b - __libc_start_main_impl
36: 0x5649969720a5 - _start
37: 0x0 - <unknown>
```
</details>
note particularly frames 13-21, from start_backtrace to end_backtrace. with PrintFmt::Short, these are the *only* frames that are printed; i.e. we are doing the exact opposite of the comment.
r? ``@saethlin``
The existing comments were misleading, confusing, and wrong.
Take this comment for example:
```
// Any frames between `__rust_begin_short_backtrace` and `__rust_end_short_backtrace`
// are omitted from the backtrace in short mode, `__rust_end_short_backtrace` will be
// called before the panic hook, so we won't ignore any frames if there is no
// invoke of `__rust_begin_short_backtrace`.
```
this is just wrong. here is an example (full) backtrace:
```
Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.01s
Running `/home/jyn/.local/lib/cargo/target/debug/example`
called `Option::unwrap()` on a `None` value
stack backtrace:
0: 0x56499698c595 - std::backtrace_rs::backtrace::libunwind::trace::h5ef2cc16e9a7415a
1: 0x56499698c595 - std::backtrace_rs::backtrace::trace_unsynchronized::h9b5e016e9075f714
2: 0x56499698c595 - std::sys_common::backtrace::_print_fmt::h2f62c7f9ff224e93
3: 0x56499698c595 - <std::sys_common::backtrace::_print::DisplayBacktrace as core::fmt::Display>::fmt::hbe51682735731910
4: 0x5649969aa26b - core::fmt::rt::Argument::fmt::h1994ab2b310d665e
5: 0x5649969aa26b - core::fmt::write::hade58a36d63468d7
6: 0x56499698a43f - std::io::Write::write_fmt::h16145587d801a9ab
7: 0x56499698c36e - std::sys_common::backtrace::_print::ha8082e56201dadb4
8: 0x56499698c36e - std::sys_common::backtrace::print::he30f96b4e7f6cbfd
9: 0x56499698d709 - std::panicking::default_hook::{{closure}}::hf0801f6b18a968d3
10: 0x56499698d4ac - std::panicking::default_hook::hd2defec7eda5aeb0
11: 0x56499698dc31 - std::panicking::rust_panic_with_hook::hde93283600065c53
12: 0x56499698daf3 - std::panicking::begin_panic_handler::{{closure}}::h5e151adbdb7ec0c1
13: 0x56499698ca59 - std::sys_common::backtrace::__rust_end_short_backtrace::he36a1407e0f77700
14: 0x56499698d7d4 - rust_begin_unwind
15: 0x5649969a9503 - core::panicking::panic_fmt::h2380d41365f95412
16: 0x5649969a958c - core::panicking::panic::h38cf8db80e8c6e67
17: 0x5649969a93e9 - core::option::unwrap_failed::he72696e53ff29a05
18: 0x5649969722b6 - core::option::Option<T>::unwrap::hb574dc0dc1703062
19: 0x5649969722b6 - example::main::h7a867aafacd93d75
20: 0x5649969721db - core::ops::function::FnOnce::call_once::h734f99a5e57291b7
21: 0x56499697226e - std::sys_common::backtrace::__rust_begin_short_backtrace::h02f5d58c351c4756
22: 0x564996972241 - std::rt::lang_start::{{closure}}::h8b134fe2c31a4355
23: 0x564996988662 - core::ops::function::impls::<impl core::ops::function::FnOnce<A> for &F>::call_once::h88d7bb571ee2aaf4
24: 0x564996988662 - std::panicking::try::do_call::hfb78dfb6599c871d
25: 0x564996988662 - std::panicking::try::habd041c8c4c8e50c
27: 0x564996988662 - std::rt::lang_start_internal::{{closure}}::h227591a6f9c0879e
28: 0x564996988662 - std::panicking::try::do_call::h3c5878333c38916a
29: 0x564996988662 - std::panicking::try::h5af7b3a127cdae70
31: 0x564996988662 - std::rt::lang_start_internal::hbc85e809eeace0dd
32: 0x56499697221a - std::rt::lang_start::ha1eb16922c9cb224
33: 0x5649969722ee - main
34: 0x7f031962a1ca - __libc_start_call_main
35: 0x7f031962a28b - __libc_start_main_impl
36: 0x5649969720a5 - _start
37: 0x0 - <unknown>
```
note particularly frames 13-21, from start_backtrace to end_backtrace. with PrintFmt::Short, these are the *only* frames that are printed; i.e. we are doing the exact opposite of the comment.
a release operation synchronizes with an acquire operation
Change:
1. `Calls to park _synchronize-with_ calls to unpark` to `Calls to unpark _synchronize-with_ calls to park`
2. `park synchronizes-with _all_ prior unpark operations` to `_all_ prior unpark operations synchronize-with park`
fix: hurd build, stat64.st_fsid was renamed to st_dev
On hurd, `stat64.st_fsid` was renamed to `st_dev` in https://github.com/rust-lang/libc/pull/3785, so if you have a new libc with this patch included, and you build std from source, you get this error:
```sh
error[E0609]: no field `st_fsid` on type `&stat64`
--> /home/runner/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/std/src/os/hurd/fs.rs:301:36
|
301 | self.as_inner().as_inner().st_fsid as u64
| ^^^^^^^ unknown field
|
help: a field with a similar name exists
|
301 | self.as_inner().as_inner().st_uid as u64
| ~~~~~~
```
Full CI log: https://github.com/nix-rust/nix/actions/runs/12033180710/job/33546728266?pr=2544
std: refactor `pthread`-based synchronization
The non-trivial code for `pthread_condvar` is duplicated across the thread parking and the `Mutex`/`Condvar` implementations. This PR moves that code into `sys::pal`, which now exposes an `unsafe` wrapper type for `pthread_mutex_t` and `pthread_condvar_t`.
thread::available_parallelism for wasm32-wasip1-threads
The target has limited POSIX support and provides the `libc::sysconf` function which allows querying the number of available CPUs.
Fix and undeprecate home_dir()
`home_dir()` has been deprecated for 6 years due to using `HOME` env var on Windows.
It's been a long time, and having a perpetually buggy and deprecated function in the standard library is not useful. I propose fixing and undeprecating it.
6 years seems more than long enough to warn users against relying on this function. The change in behavior is minor, and it's more of a bug fix than breakage. The old behavior is unlikely to be useful, and even if anybody actually needed to specifically use the non-standard `HOME` on Windows, they can trivially mitigate this change by reading the env var themselves.
----
Use of `USERPROFILE` is in line with the `home` crate: 37bc5f0232/crates/home/src/windows.rs (L12)
The `home` crate uses `SHGetKnownFolderPath` instead of `GetUserProfileDirectoryW`. AFAIK it doesn't make any difference in practice, because `SHGetKnownFolderPath` merely adds support for more kinds of folders, including virtual (non-filesystem) folders identified by a GUID, but the specific case of [`FOLDERID_Profile`](https://learn.microsoft.com/en-us/windows/win32/shell/knownfolderid#FOLDERID_Profile) is documented as a FIXED folder (a regular filesystem path). Just in case, I've added a note to documentation that the use of `GetUserProfileDirectoryW` can change.
I've used `CURRENT_RUSTC_VERSION` in a doccomment. `replace-version-placeholder` tool seems to perform a simple string replacement, so hopefully it'll get updated.
Stabilize `extended_varargs_abi_support`
I think that is everything? If there is any documentation regarding `extern` and/or varargs to correct, let me know, some quick greps suggest that there might be none.
Tracking issue: https://github.com/rust-lang/rust/issues/100189
Bump boostrap compiler to new beta
Currently failing due to something about the const stability checks and `panic!`. I'm not sure why though since I wasn't able to see any PRs merged in the past few days that would result in a `cfg(bootstrap)` that shouldn't be removed. cc `@RalfJung` #131349
Use consistent wording in docs, use is zero instead of is 0
In documentation, wording of _"`rhs` is zero"_ and _"`rhs` is 0"_ is intermixed. This is especially visible [here](https://doc.rust-lang.org/std/primitive.usize.html#method.div_ceil).
This changes all occurrences to _"`rhs` is zero"_ for better readability.
Enable -Zshare-generics for inline(never) functions
This avoids inlining cross-crate generic items when possible that are
already marked inline(never), implying that the author is not intending
for the function to be inlined by callers. As such, having a local copy
may make it easier for LLVM to optimize but mostly just adds to binary
bloat and codegen time. In practice our benchmarks indicate this is
indeed a win for larger compilations, where the extra cost in dynamic
linking to these symbols is diminished compared to the advantages in
fewer copies that need optimizing in each binary.
It might also make sense it expand this with other heuristics (e.g.,
`#[cold]`) in the future, but this seems like a good starting point.
FWIW, I expect that doing cleanup in where we make the decision
what should/shouldn't be shared is also a good idea. Way too
much code needed to be tweaked to check this. But I'm hoping
to leave that for a follow-up PR rather than blocking this on it.
This reduces code sizes and better respects programmer intent when
marking inline(never). Previously such a marking was essentially ignored
for generic functions, as we'd still inline them in remote crates.
Rollup of 12 pull requests
Successful merges:
- #129409 (Expand std::os::unix::fs::chown() doc with a warning)
- #133320 (Add release notes for Rust 1.83.0)
- #133368 (Delay a bug when encountering an impl with unconstrained generics in `codegen_select`)
- #133428 (Actually use placeholder regions for trait method late bound regions in `collect_return_position_impl_trait_in_trait_tys`)
- #133512 (Add `as_array` and `as_mut_array` conversion methods to slices.)
- #133519 (Check `xform_ret_ty` for WF in the new solver to improve method winnowing)
- #133520 (Structurally resolve before applying projection in borrowck)
- #133534 (extend group-forbid-always-trumps-cli test)
- #133537 ([rustdoc] Fix new clippy lints)
- #133543 ([AIX] create shim for lgammaf_r)
- #133547 (rustc_span: Replace a `HashMap<_, ()>` with `HashSet`)
- #133550 (print generated doc paths)
r? `@ghost`
`@rustbot` modify labels: rollup
[AIX] create shim for lgammaf_r
On AIX, we don't have 32bit floating point for re-entrant `lgammaf_r` but we do have the 64bit floating point re-entrant `lgamma_r` so we can use the 64bit version instead and truncate back to a 32bit float.
This solves the linker missing symbol for `.lgammaf_r` when testing and using these parts of the `std`.
Expand std::os::unix::fs::chown() doc with a warning
Include warning about losing setuid/gid when chowning, per POSIX.
It is about the underlying system call but it is rather useful to mention it in the help in case someone accidentally forgets (don't look at me :)).
std:🧵 avoid leading whitespace in some panic messages
This:
```
panic!(
"use of std:🧵:current() is not possible after the thread's
local data has been destroyed"
)
```
will print a newline followed by a bunch of spaces, since the entire string literal is interpreted literally.
I think the intention was to print the message without the newline and the spaces, so let's add some `\` to make that happen.
r? ``@joboet``
Added a doc test for std::path::strip_prefix
I was about 90% sure `Path::new("/test/haha/foo.txt").strip_prefix("/te")` would return an Err, but I couldn't find an example to confirm this behaviour.
This should be an easy merge :)
Mention that std::fs::remove_dir_all fails on files
This is explicitly mentioned for std::fs::remove_file.
It is more likely for a slightly lazy programmer to believe that removing a file would work and that they do not have to distinguish between directories (with contents) and files themself, because of the function's recursive nature and how it distinguishes between files and directories when removing them.
Follow-up for #133183.
std: allow after-main use of synchronization primitives
By creating an unnamed thread handle when the actual one has already been destroyed, synchronization primitives using thread parking can be used even outside the Rust runtime.
This also fixes an inefficiency in the queue-based `RwLock`: if `thread::current` was not initialized yet, it will create a new handle on every parking attempt without initializing `thread::current`. The private `current_or_unnamed` function introduced here fixes this.
Add `AsyncFn*` to the prelude in all editions
The general vibe is that we will most likely stabilize the `feature(async_closure)` *without* the `async Fn()` trait bound modifier.
Without `async Fn()` bound syntax, this necessitates users to spell the bound like `AsyncFn()`. Since `core::ops::AsyncFn` is not in the prelude, users will need to import these any time they actually want to use the trait. This seems annoying, so let's add these traits to the prelude unstably.
We're trying to work on the general vision of `async` trait bound modifier in general in: https://github.com/rust-lang/rfcs/pull/3710, however that RFC still needs more time for consensus to converge, and we've decided that the value that users get from calling the bound `async Fn()` is *not really* worth blocking landing async closures in general.
This is explicitly mentioned for std::fs::remove_file's documentation,
but not in the aforementioned function.
It is more likely for a slightly lazy programmer to believe that
removing a file would work and that they do not have to distinguish
between directories (with contents) and files themself, because of the
function's recursive nature and how it distinguishes between files and
directories when removing them.
Emscripten: link with -sWASM_BIGINT
When linking an executable without dynamic linking, this is a pure improvement. It significantly reduces code size and avoids a lot of buggy behaviors. It is supported in all browsers for many years and in all maintained versions of Node.
It does change the ABI, so people who are dynamically linking with a library or executable that uses the old ABI may need to turn it off. It can be disabled if needed by passing `-Clink-arg -sWASM_BIGINT=0` to `rustc`. But few people will want to turn it off.
Note this includes a libc bump to 0.2.162!
Mark `get_mut` and `set_position` in `std::io::Cursor` as const.
Relevant tracking issue: #130801
The methods `get_mut` and `set_position` can trivially be marked as const due to #57349 being stabilised.
Rollup of 4 pull requests
Successful merges:
- #131081 (Use `ConstArgKind::Path` for all single-segment paths, not just params under `min_generic_const_args`)
- #132577 (Report the `unexpected_cfgs` lint in external macros)
- #133023 (Merge `-Zhir-stats` into `-Zinput-stats`)
- #133200 (ignore an occasionally-failing test in Miri)
r? `@ghost`
`@rustbot` modify labels: rollup
Improve `{BTreeMap,HashMap}::get_key_value` docs.
They are unusual methods. The docs don't really describe the cases when they might be useful (as opposed to just `get`), and the examples don't demonstrate the interesting cases at all.
This commit improves the docs and the examples.
When upgrading [Zed](https://github.com/zed-industries/zed/pull/19349) to Rust 1.82 I've encountered a test failure in our test suite. Specifically, one of our extension tests started hanging. I've tracked it down to a call to std::fs::remove_dir_all not returning when an extension is compiled with Rust 1.82
Our extension system uses WASM components, thus I've looked at the diff between 1.81 and 1.82 with respect to WASI and found 736f773844
As it turned out, calling remove_dir_all from extension returned io::ErrorKind::NotFound in 1.81;
the underlying issue is that the ReadDir iterator never actually terminates iteration, however since it loops around, with 1.81 we'd come across an entry second time and fail to remove it, since it would've been removed previously.
With 1.82 and 736f773844 it is no longer the case, thus we're seeing the hang.
This commit makes ReadDir::next adhere to readdir contract, namely it will no longer call readdir once the returned # of bytes is smaller than the size of a passed-in buffer.
Previously we'd only terminate the loop if readdir returned 0.
By creating an unnamed thread handle when the actual one has already been destroyed, synchronization primitives using thread parking can be used even outside the Rust runtime.
This also fixes an inefficiency in the queue-based `RwLock`: if `thread::current` was not initialized yet, it will create a new handle on every parking attempt without initializing `thread::current`. The private `current_or_unnamed` function introduced here fixes this.
Rwlock downgrade
Tracking Issue: #128203
This PR adds a `downgrade` method for `RwLock` / `RwLockWriteGuard` on all currently supported platforms.
Outstanding questions:
- [x] ~~Does the `futex.rs` change affect performance at all? It doesn't seem like it will but we can't be certain until we bench it...~~
- [x] ~~Should the SOLID platform implementation [be ported over](https://github.com/rust-lang/rust/pull/128219#discussion_r1693470090) to the `queue.rs` implementation to allow it to support downgrades?~~
They are unusual methods. The docs don't really describe the cases when
they might be useful (as opposed to just `get`), and the examples don't
demonstrate the interesting cases at all.
This commit improves the docs and the examples.
This commit fixes a memory ordering bug in the futex implementation
(`Relaxed` -> `Release` on `downgrade`).
This commit also removes a badly written test that deadlocked and
replaces it with a more reasonable test based on an already-tested
`downgrade` test from the parking-lot crate.
This commit adds the `downgrade` method onto the inner `RwLock` queue
implementation.
There are also a few other style patches included in this commit.
Co-authored-by: Jonas Böttiger <jonasboettiger@icloud.com>
This commit only has documentation changes and a few things moved around
the file. The very few code changes are cosmetic: changes like turning a
`match` statement into an `if let` statement or reducing indentation for
long if statements.
This commit also adds several safety comments on top of `unsafe` blocks
that might not be immediately obvious to a first-time reader.
Code "changes" are in:
- `add_backlinks_and_find_tail`
- `lock_contended`
A majority of the changes are just expanding the comments from 80
columns to 100 columns.
[illumos] use pipe2 to create anonymous pipes
pipe2 allows the newly-created pipe to atomically be CLOEXEC.
pipe2 was added to illumos a long time ago:
5dbfd19ad5. I've verified that this change passes all of std's tests on illumos.
Fix compilation error on Solaris due to flock usage
PR 130999 added the file_lock feature, but libc does not define flock() for the Solaris platform leading to a compilation error.
Additionally, I went through all the Tier 2 platforms and read through their documentation to see whether flock was implemented. This turned up 5 more Unix platforms where flock is not supported, even though it may exist in the libc crate.
Fixes https://github.com/rust-lang/rust/issues/132921
Related to #130999
Fix a copy-paste issue in the NuttX raw type definition
This file is copied from the rtems as initial implementation, and forgot to change the OS name in the comment.
This file is copied from the rtems as initial implementation, and
forgot to change the OS name in the comment.
Signed-off-by: Huang Qi <huangqi3@xiaomi.com>
Make `CloneToUninit` dyn-compatible
Make `CloneToUninit` dyn-compatible, by making `clone_to_uninit`'s `dst` parameter `*mut u8` instead of `*mut Self`, so the method does not reference `Self` except in the `self` parameter and is thus dispatchable from a trait object.
This allows, among other things, adding `CloneToUninit` as a supertrait bound for `trait Foo` to allow cloning `dyn Foo` in some containers. Currently, this means that `Rc::make_mut` and `Arc::make_mut` can work with `dyn Foo` where `trait Foo: CloneToUninit`.
<details><summary>Example</summary>
```rs
#![feature(clone_to_uninit)]
use std::clone::CloneToUninit;
use std::rc::Rc;
use std::fmt::Debug;
use std::borrow::BorrowMut;
trait Foo: BorrowMut<u32> + CloneToUninit + Debug {}
impl<T: BorrowMut<u32> + CloneToUninit + Debug> Foo for T {}
fn main() {
let foo: Rc<dyn Foo> = Rc::new(42_u32);
let mut bar = foo.clone();
*Rc::make_mut(&mut bar).borrow_mut() = 37;
dbg!(foo, bar); // 42, 37
}
```
</details>
Eventually, `Box::<T>::clone` is planned to be converted to use `T::clone_to_uninit`, which when combined with this change, will allow cloning `Box<dyn Foo>` where `trait Foo: CloneToUninit` without any additional `unsafe` code for the author of `trait Foo`.[^1]
This PR should have no stable side-effects, as `CloneToUninit` is unstable so cannot be mentioned on stable, and `CloneToUninit` is not used as a supertrait anywhere in the stdlib.
This change removes some length checks that could only fail if library UB was already hit (e.g. calling `<[T]>::clone_to_uninit` with a too-small-length `dst` is library UB and was previously detected[^2]; since `dst` does not have a length anymore, this now cannot be detected[^3]).
r? libs-api
-----
I chose to make the parameter `*mut u8` instead of `*mut ()` because that might make it simpler to pass the result of `alloc` to `clone_to_uninit`, but `*mut ()` would also make sense, and any `*mut ConcreteType` would *work*. The original motivation for [using specifically `*mut ()`](https://github.com/rust-lang/rust/pull/116113#discussion_r1335303908) appears to be `std::ptr::from_raw_parts_mut`, but that now [takes `*mut impl Thin`](https://doc.rust-lang.org/nightly/std/ptr/fn.from_raw_parts.html) instead of `*mut ()`. I have another branch where the parameter is `*mut ()`, if that is preferred.
It *could* also take something like `&mut [MaybeUninit<u8>]` to be dyn-compatible but still allow size-checking and in some cases safe writing, but this is already an `unsafe` API where misuse is UB, so I'm not sure how many guardrails it's worth adding here, and `&mut [MaybeUninit<u8>]` might be overly cumbersome to construct for callers compared to `*mut u8`
[^1]: Note that `impl<T: CloneToUninit + ?Sized> Clone for Box` must be added before or at the same time as when `CloneToUninit` becomes stable, due to `Box` being `#[fundamental]`, as if there is any stable gap between the stabilization of `CloneToUninit` and `impl<T: CloneToUninit + ?Sized> Clone for Box`, then users could implement both `CloneToUninit for dyn LocalTrait` and separately `Clone for Box<dyn LocalTrait>` during that gap, and be broken by the introduction of `impl<T: CloneToUninit + ?Sized> Clone for Box`.
[^2]: Using a `debug_assert_eq` in [`core::clone::uninit::CopySpec::clone_slice`](https://doc.rust-lang.org/nightly/src/core/clone/uninit.rs.html#28).
[^3]: This PR just uses [the metadata (length) from `self`](e0c1c8bc50/library/core/src/clone.rs (L286)) to construct the `*mut [T]` to pass to `CopySpec::clone_slice` in `<[T]>::clone_to_uninit`.
float types: move copysign, abs, signum to libcore
These operations are explicitly specified to act "bitwise", i.e. they just act on the sign bit and do not even quiet signaling NaNs. We also list them as ["non-arithmetic operations"](https://doc.rust-lang.org/nightly/std/primitive.f32.html#nan-bit-patterns), and all the other non-arithmetic operations are in libcore. There's no reason to expect them to require any sort of runtime support, and from [these experiments](https://github.com/rust-lang/rust/issues/50145#issuecomment-997301250) it seems like LLVM indeed compiles them in a way that does not require any sort of runtime support.
Nominating for `@rust-lang/libs-api` since this change takes immediate effect on stable.
Part of https://github.com/rust-lang/rust/issues/50145.
PR 130999 added the file_lock feature, but libc does not define
flock() for the Solaris platform leading to a compilation error.
Additionally, I went through all the Tier 2 platforms and read through
their documentation to see whether flock was implemented. This turned up
5 more Unix platforms where flock is not supported, even though it may
exist in the libc crate.
pipe2 allows the newly-created pipe to atomically be CLOEXEC.
pipe2 was added to illumos a long time ago:
5dbfd19ad5.
I've verified that this change passes all tests.
split up the first paragraph of doc comments for better summaries
used `./x clippy -Aclippy::all '-Wclippy::too_long_first_doc_paragraph' library/core library/alloc` to find these issues.
When linking an executable without dynamic linking, this is a pure improvement.
It significantly reduces code size and avoids a lot of buggy behaviors. It is
supported in all browsers for many years and in all maintained versions of
Node.
It does change the ABI, so people who are dynamically linking with a library
or executable that uses the old ABI may need to turn it off. It can be disabled
if needed by passing `-Clink-arg -sWASM_BIGINT=0` to `rustc`. But few people
will want to turn it off.
Implement file_lock feature
This adds lock(), lock_shared(), try_lock(), try_lock_shared(), and unlock() to File gated behind the file_lock feature flag
This is the initial implementation of https://github.com/rust-lang/rust/issues/130994 for Unix and Windows platforms. I will follow it up with an implementation for WASI preview 2
Initialize channel `Block`s directly on the heap
The channel's `Block::new` was causing a stack overflow because it held
32 item slots, instantiated on the stack before moving to `Box::new`.
The 32x multiplier made modestly-large item sizes untenable.
That block is now initialized directly on the heap.
Fixes#102246
try-job: test-various
Compile `test_num_f128` conditionally on `reliable_f128_math` config
With #132434 merged, our internal SGX CI started failing with:
```
05:27:34 = note: rust-lld: error: undefined symbol: fmodl
05:27:34 >>> referenced by arith.rs:617 (core/src/ops/arith.rs:617)
05:27:34 >>> /home/jenkins/workspace/rust-sgx-ci/rust/build/x86_64-unknown-linux-gnu/stage1-std/x86_64-fortanix-unknown-sgx/release/deps/std-5d5f11eb008c9091.std.d8141acc61ab7ac8-cgu.10.rcgu.o:(std::num::test_num::h7dd9449f6c01fde8)
05:27:34 >>> did you mean: fmodf
05:27:34 >>> defined in: /home/jenkins/workspace/rust-sgx-ci/rust/build/x86_64-unknown-linux-gnu/stage1-std/x86_64-fortanix-unknown-sgx/release/deps/libcompiler_builtins-0376f439a2ebf305.rlib(compiler_builtins-0376f439a2ebf305.compiler_builtins.c22db39d25d6f802-cgu.148.rcgu.o)
```
This originated from the `test_num_f128` test not having the required conditional compilation. This PR fixes that issue.
cc: ````@jethrogb,```` ````@workingjubilee````
The channel's `Block::new` was causing a stack overflow because it held
32 item slots, instantiated on the stack before moving to `Box::new`.
The 32x multiplier made modestly-large item sizes untenable.
That block is now initialized directly on the heap.
Fixes#102246
unpin and update memchr
I'm unable to build x86_64-pc-windows-gnu Rust due to some weird binutils bug, but thinlto issue seems to be no longer present. Let's give it a go on the CI.
Possibly fixed by https://github.com/rust-lang/rust/pull/129079Fixes#127890
Revert using `HEAP` static in Windows alloc
Fixes#131468
This does the minimum to remove the `HEAP` static that was causing chromium issues. It would be worth having a more substantial look at this module but for now I think this addresses the immediate issue.
cc `@danakj`
Fix an extra newline in rendered std doc
Fixes#132564
(taken from the issue above)
The problem with the formatting is due to that newline between `<code>` and `<svg>`. Any newlines outside of the code (i.e., within elements inside of it) are fine.
Update `compiler-builtins` and enable f128 tests on all non-buggy platforms
Update compiler_builtins to 0.1.138 and pin it. This updates to a new version of builtins that includes [1], which was
the last blocker to us enabling `f128` tests on all platforms.
With that, we now provide symbols necessary to work with `f128` everywhere. This means that we are no longer restricted to systems that provide `f128` symbols themselves, and can enable tests by default.
There are still a handful of platforms that need to remain disabled because of bugs and some that had to get updated.
Math support is still off by default since those symbols are not yet available.
[1]: https://github.com/rust-lang/compiler-builtins/pull/624
try-job: test-various
try-job: i686-gnu-nopt
With the `compiler-builtins` update to 0.1.137 [1], we now provide
symbols necessary to work with `f128` everywhere. This means that we are
no longer restricted to 64-bit linux, and can enable tests by default.
There are still a handful of platforms that need to remain disabled
because of bugs. This patch additionally disables the following:
1. MIPS [2]
2. 32-bit x86 [3]
Math support is still off by default since those symbols are not yet
available.
[1]: https://github.com/rust-lang/rust/pull/132433
[2]: https://github.com/llvm/llvm-project/issues/96432
[3]: https://github.com/llvm/llvm-project/issues/77401
This updates to a new version of builtins that includes [1], which was
the last blocker to us enabling `f128` tests on all platforms 🎉.
With this update, also change to pinning the version with `=` rather
than using the default carat versioning. This is meant to ensure that
`compiler-builtins` does not get updated as part of the weekly
`Cargo.lock` update, since updates to this crate need to be intentional:
changes to rust-lang/rust and rust-lang/compiler-builtins sometimes need
to be kept in lockstep, unlike most dependencies, and sometimes these
updates can be problematic.
[1]: https://github.com/rust-lang/compiler-builtins/pull/624
Make `std::os::darwin` public
I'm not sure of the reasoning behind them not being public before, but I think they should be, just like `std::os::ios` and `std::os::macos` are public.
Additionally, I've merged their source code, as it was otherwise just a bunch of unnecessary duplication.
Ultimately, I've done this PR to fix `./x build library --target=aarch64-apple-tvos,aarch64-apple-watchos,aarch64-apple-visionos`, as that currently fails because of dead code warnings.
Since you reviewed https://github.com/rust-lang/rust/pull/121419
r? davidtwco
Fixes https://github.com/rust-lang/rust/issues/121640.
`@rustbot` label O-tvos O-watchos O-visionos
better test for const HashMap; remove const_hash leftovers
The existing `const_with_hasher` test is kind of silly since the HashMap it constructs can never contain any elements. So this adjusts the test to construct a usable HashMap, which is a bit non-trivial since the default hash builder cannot be built in `const`. `BuildHasherDefault::new()` helps but is unstable (https://github.com/rust-lang/rust/issues/123197), so we also have a test that does not involve that type.
The second commit removes the last remnants of https://github.com/rust-lang/rust/issues/104061, since they aren't actually useful -- without const traits, you can't do any hashing in `const`.
Cc ``@rust-lang/libs-api`` ``@rust-lang/wg-const-eval``
Closes#104061
Related to https://github.com/rust-lang/rust/issues/102575
Implement `From<&mut {slice}>` for `Box/Rc/Arc<{slice}>`
ACP: https://github.com/rust-lang/libs-team/issues/424
New API:
```rust
impl<T: Clone> From<&mut [T]> for Box<[T]>
impl From<&mut str> for Box<str>
impl From<&mut CStr> for Box<CStr>
impl From<&mut OsStr> for Box<OsStr>
impl From<&mut Path> for Box<Path>
impl<T: Clone> From<&mut [T]> for Rc<[T]>
impl From<&mut str> for Rc<str>
impl From<&mut CStr> for Rc<CStr>
impl From<&mut OsStr> for Rc<OsStr>
impl From<&mut Path> for Rc<Path>
impl<T: Clone> From<&mut [T]> for Arc<[T]>
impl From<&mut str> for Arc<str>
impl From<&mut CStr> for Arc<CStr>
impl From<&mut OsStr> for Arc<OsStr>
impl From<&mut Path> for Arc<Path>
```
Since they are trait implementations, I think these are insta-stable.
As mentioned in https://github.com/rust-lang/libs-team/issues/424#issuecomment-2299415749, a crater run might be needed.
Remove unintended link
Since `#[link_section]` is enclosed in braces, it was being confused with a link during docs compilation.
This caused compilation to fail when running `x dist` since it emitted a warning regarding broken links.
Fix type reference in documents which was being confused with html tags.
Running `x dist` was failing due to it invoking commands with `-D warnings`, which emitted a warning about unclosed html tags.
xous: sync: remove `rustc_const_stable` attribute on Condvar and Mutex new()
These functions had `#[rustc_const_stable(feature = "const_locks", since = "1.63.0")]` on them because they were originally taken from `no_threads`. with d066dfd these no longer compile. Since other platforms do not have this attribute, remove it. This fixes the build for Xous.
These functions had `#[rustc_const_stable(feature = "const_locks", since
= "1.63.0")]` on them because they were originally taken from
`no_threads`. with d066dfd these no longer compile. Since other
platforms do not have this attribute, remove it. This fixes the build
for Xous.
Signed-off-by: Sean Cross <sean@xobs.io>
The non-trivial code for `pthread_condvar` is duplicated across the thread parking and the `Mutex`/`Condvar` implementations. This PR moves that code into `sys::pal`, which now exposes a non-movable wrapper type for `pthread_mutex_t` and `pthread_condvar_t`.
Const stability checks v2
The const stability system has served us well ever since `const fn` were first stabilized. It's main feature is that it enforces *recursive* validity -- a stable const fn cannot internally make use of unstable const features without an explicit marker in the form of `#[rustc_allow_const_fn_unstable]`. This is done to make sure that we don't accidentally expose unstable const features on stable in a way that would be hard to take back. As part of this, it is enforced that a `#[rustc_const_stable]` can only call `#[rustc_const_stable]` functions. However, some problems have been coming up with increased usage:
- It is baffling that we have to mark private or even unstable functions as `#[rustc_const_stable]` when they are used as helpers in regular stable `const fn`, and often people will rather add `#[rustc_allow_const_fn_unstable]` instead which was not our intention.
- The system has several gaping holes: a private `const fn` without stability attributes whose inherited stability (walking up parent modules) is `#[stable]` is allowed to call *arbitrary* unstable const operations, but can itself be called from stable `const fn`. Similarly, `#[allow_internal_unstable]` on a macro completely bypasses the recursive nature of the check.
Fundamentally, the problem is that we have *three* disjoint categories of functions, and not enough attributes to distinguish them:
1. const-stable functions
2. private/unstable functions that are meant to be callable from const-stable functions
3. functions that can make use of unstable const features
Functions in the first two categories cannot use unstable const features and they can only call functions from the first two categories.
This PR implements the following system:
- `#[rustc_const_stable]` puts functions in the first category. It may only be applied to `#[stable]` functions.
- `#[rustc_const_unstable]` by default puts functions in the third category. The new attribute `#[rustc_const_stable_indirect]` can be added to such a function to move it into the second category.
- `const fn` without a const stability marker are in the second category if they are still unstable. They automatically inherit the feature gate for regular calls, it can now also be used for const-calls.
Also, all the holes mentioned above have been closed. There's still one potential hole that is hard to avoid, which is when MIR building automatically inserts calls to a particular function in stable functions -- which happens in the panic machinery. Those need to be manually marked `#[rustc_const_stable_indirect]` to be sure they follow recursive const stability. But that's a fairly rare and special case so IMO it's fine.
The net effect of this is that a `#[unstable]` or unmarked function can be constified simply by marking it as `const fn`, and it will then be const-callable from stable `const fn` and subject to recursive const stability requirements. If it is publicly reachable (which implies it cannot be unmarked), it will be const-unstable under the same feature gate. Only if the function ever becomes `#[stable]` does it need a `#[rustc_const_unstable]` or `#[rustc_const_stable]` marker to decide if this should also imply const-stability.
Adding `#[rustc_const_unstable]` is only needed for (a) functions that need to use unstable const lang features (including intrinsics), or (b) `#[stable]` functions that are not yet intended to be const-stable. Adding `#[rustc_const_stable]` is only needed for functions that are actually meant to be directly callable from stable const code. `#[rustc_const_stable_indirect]` is used to mark intrinsics as const-callable and for `#[rustc_const_unstable]` functions that are actually called from other, exposed-on-stable `const fn`. No other attributes are required.
Also see the updated dev-guide at https://github.com/rust-lang/rustc-dev-guide/pull/2098.
I think in the future we may want to tweak this further, so that in the hopefully common case where a public function's const-stability just exactly mirrors its regular stability, we never have to add any attribute. But right now, once the function is stable this requires `#[rustc_const_stable]`.
### Open question
There is one point I could see we might want to do differently, and that is putting `#[rustc_const_unstable]` functions (but not intrinsics) in category 2 by default, and requiring an extra attribute for `#[rustc_const_not_exposed_on_stable]` or so. This would require a bunch of extra annotations, but would have the advantage that turning a `#[rustc_const_unstable]` into `#[rustc_const_stable]` will never change the way the function is const-checked. Currently, we often discover in the const stabilization PR that a function needs some other unstable const things, and then we rush to quickly deal with that. In this alternative universe, we'd work towards getting rid of the `rustc_const_not_exposed_on_stable` before stabilization, and once that is done stabilization becomes a trivial matter. `#[rustc_const_stable_indirect]` would then only be used for intrinsics.
I think I like this idea, but might want to do it in a follow-up PR, as it will need a whole bunch of annotations in the standard library. Also, we probably want to convert all const intrinsics to the "new" form (`#[rustc_intrinsic]` instead of an `extern` block) before doing this to avoid having to deal with two different ways of declaring intrinsics.
Cc `@rust-lang/wg-const-eval` `@rust-lang/libs-api`
Part of https://github.com/rust-lang/rust/issues/129815 (but not finished since this is not yet sufficient to safely let us expose `const fn` from hashbrown)
Fixes https://github.com/rust-lang/rust/issues/131073 by making it so that const-stable functions are always stable
try-job: test-various
Fundamentally, we have *three* disjoint categories of functions:
1. const-stable functions
2. private/unstable functions that are meant to be callable from const-stable functions
3. functions that can make use of unstable const features
This PR implements the following system:
- `#[rustc_const_stable]` puts functions in the first category. It may only be applied to `#[stable]` functions.
- `#[rustc_const_unstable]` by default puts functions in the third category. The new attribute `#[rustc_const_stable_indirect]` can be added to such a function to move it into the second category.
- `const fn` without a const stability marker are in the second category if they are still unstable. They automatically inherit the feature gate for regular calls, it can now also be used for const-calls.
Also, several holes in recursive const stability checking are being closed.
There's still one potential hole that is hard to avoid, which is when MIR
building automatically inserts calls to a particular function in stable
functions -- which happens in the panic machinery. Those need to *not* be
`rustc_const_unstable` (or manually get a `rustc_const_stable_indirect`) to be
sure they follow recursive const stability. But that's a fairly rare and special
case so IMO it's fine.
The net effect of this is that a `#[unstable]` or unmarked function can be
constified simply by marking it as `const fn`, and it will then be
const-callable from stable `const fn` and subject to recursive const stability
requirements. If it is publicly reachable (which implies it cannot be unmarked),
it will be const-unstable under the same feature gate. Only if the function ever
becomes `#[stable]` does it need a `#[rustc_const_unstable]` or
`#[rustc_const_stable]` marker to decide if this should also imply
const-stability.
Adding `#[rustc_const_unstable]` is only needed for (a) functions that need to
use unstable const lang features (including intrinsics), or (b) `#[stable]`
functions that are not yet intended to be const-stable. Adding
`#[rustc_const_stable]` is only needed for functions that are actually meant to
be directly callable from stable const code. `#[rustc_const_stable_indirect]` is
used to mark intrinsics as const-callable and for `#[rustc_const_unstable]`
functions that are actually called from other, exposed-on-stable `const fn`. No
other attributes are required.
Avoid using imports in thread_local_inner! in static
Fixes#131863 for wasm targets
All other macros were done in #131866, but this sub module is missed.
r? `@jieyouxu`
AIX: use /dev/urandom for random implementation
On AIX, we can poll `/dev/urandom` for cryptographically secure random output to implement `fill_bytes` because we don't have equivalent syscalls like other platforms. https://www.ibm.com/docs/en/aix/7.3?topic=files-random-urandom-devices
[musl] use posix_spawn if a directory change was requested
Currently, not all libcs have the `posix_spawn_file_actions_addchdir_np` symbol available to them. So we attempt to do a weak symbol lookup for that function. But that only works if libc is a dynamic library -- with statically linked musl binaries the symbol lookup would never work, so we would never be able to use it even if the musl in use supported the symbol.
Now that Rust has a minimum musl version of 1.2.3, all supported musl versions now include this symbol, so we can unconditionally expect it to be there. This symbol was added to libc in https://github.com/rust-lang/libc/pull/3949 -- use it here.
I couldn't find any tests for whether the posix_spawn path is used, but I've verified with cargo-nextest that this change works. This is a substantial improvement to nextest's performance with musl. On my workstation with a Ryzen 7950x, against https://github.com/clap-rs/clap at
61f5ee514f8f60ed8f04c6494bdf36c19e7a8126:
Before:
```
Summary [ 1.071s] 879 tests run: 879 passed, 0 skipped
```
After:
```
Summary [ 0.392s] 879 tests run: 879 passed, 0 skipped
```
Fixes#99740.
try-job: dist-various-1
try-job: dist-various-2
Remove the `Arc` rt::init allocation for thread info
Removes an allocation pre-main by just not storing anything in std:🧵:Thread for the main thread.
- The thread name can just be a hard coded literal, as was done in #123433.
- Storing ThreadId and Parker in a static that is initialized once at startup. This uses SyncUnsafeCell and MaybeUninit as this is quite performance critical and we don't need synchronization or to store a tag value and possibly leave in a panic.
Currently, not all libcs have the `posix_spawn_file_actions_addchdir_np` symbol
available to them. So we attempt to do a weak symbol lookup for that function.
But that only works if libc is a dynamic library -- with statically linked musl
binaries the symbol lookup would never work, so we would never be able to use it
even if the musl in use supported the symbol.
Now that Rust has a minimum musl version of 1.2.3, all supported musl versions
now include this symbol, so we can unconditionally expect it to be there. This
symbol was added to libc in https://github.com/rust-lang/libc/pull/3949 -- use
it here.
I couldn't find any tests for whether the posix_spawn path is used, but I've
verified with cargo-nextest that this change works. This is a substantial
improvement to nextest's performance with musl. On my workstation with a Ryzen
7950x, against https://github.com/clap-rs/clap at
61f5ee514f8f60ed8f04c6494bdf36c19e7a8126:
Before:
```
Summary [ 1.071s] 879 tests run: 879 passed, 0 skipped
```
After:
```
Summary [ 0.392s] 879 tests run: 879 passed, 0 skipped
```
Fixes#99740.
stabilize Strict Provenance and Exposed Provenance APIs
Given that [RFC 3559](https://rust-lang.github.io/rfcs/3559-rust-has-provenance.html) has been accepted, t-lang has approved the concept of provenance to exist in the language. So I think it's time that we stabilize the strict provenance and exposed provenance APIs, and discuss provenance explicitly in the docs:
```rust
// core::ptr
pub const fn without_provenance<T>(addr: usize) -> *const T;
pub const fn dangling<T>() -> *const T;
pub const fn without_provenance_mut<T>(addr: usize) -> *mut T;
pub const fn dangling_mut<T>() -> *mut T;
pub fn with_exposed_provenance<T>(addr: usize) -> *const T;
pub fn with_exposed_provenance_mut<T>(addr: usize) -> *mut T;
impl<T: ?Sized> *const T {
pub fn addr(self) -> usize;
pub fn expose_provenance(self) -> usize;
pub fn with_addr(self, addr: usize) -> Self;
pub fn map_addr(self, f: impl FnOnce(usize) -> usize) -> Self;
}
impl<T: ?Sized> *mut T {
pub fn addr(self) -> usize;
pub fn expose_provenance(self) -> usize;
pub fn with_addr(self, addr: usize) -> Self;
pub fn map_addr(self, f: impl FnOnce(usize) -> usize) -> Self;
}
impl<T: ?Sized> NonNull<T> {
pub fn addr(self) -> NonZero<usize>;
pub fn with_addr(self, addr: NonZero<usize>) -> Self;
pub fn map_addr(self, f: impl FnOnce(NonZero<usize>) -> NonZero<usize>) -> Self;
}
```
I also did a pass over the docs to adjust them, because this is no longer an "experiment". The `ptr` docs now discuss the concept of provenance in general, and then they go into the two families of APIs for dealing with provenance: Strict Provenance and Exposed Provenance. I removed the discussion of how pointers also have an associated "address space" -- that is not actually tracked in the pointer value, it is tracked in the type, so IMO it just distracts from the core point of provenance. I also adjusted the docs for `with_exposed_provenance` to make it clear that we cannot guarantee much about this function, it's all best-effort.
There are two unstable lints associated with the strict_provenance feature gate; I moved them to a new [strict_provenance_lints](https://github.com/rust-lang/rust/issues/130351) feature since I didn't want this PR to have an even bigger FCP. ;)
`@rust-lang/opsem` Would be great to get some feedback on the docs here. :)
Nominating for `@rust-lang/libs-api.`
Part of https://github.com/rust-lang/rust/issues/95228.
[FCP comment](https://github.com/rust-lang/rust/pull/130350#issuecomment-2395114536)
replace STATX_ALL with (STATX_BASIC_STATS | STATX_BTIME) as former is deprecated
STATX_ALL was deprecated in 581701b7ef and suggested to use equivalent (STATX_BASIC_STATS | STATX_BTIME) combination, to prevent future surprises.
Update `use` keyword docs to describe precise capturing
I noticed that the standard library keyword docs for the `use` keyword haven't been updated yet to describe the new precise capturing syntax.
Make `profiler_builtins` an optional dependency of sysroot, not std
This avoids unnecessary rebuilds of std (and the compiler) when `build.profiler` is toggled off or on.
Fixes#131812.
---
Background: The `profiler_builtins` crate has been an optional dependency of std (behind a cargo feature) ever since it was added back in #42433. But as far as I can tell that has only ever been a convenient way to force the crate to be built, not a genuine dependency.
The side-effect of this false dependency is that toggling `build.profiler` causes a rebuild of std and the compiler, which shouldn't be necessary. This PR therefore makes `profiler_builtins` an optional dependency of the dummy sysroot crate (#108865), rather than a dependency of std.
What makes this change so small is that all of the necessary infrastructure already exists. Previously, bootstrap would enable the `profiler` feature on the sysroot crate, which would forward that feature to std. Now, enabling that feature directly enables sysroot's `profiler_builtins` dependency instead.
---
I believe this is more of a bootstrap change than a libs change, so tentatively:
r? bootstrap
- Since in almost all cases, there will only be 1 UEFI shell, share the
shell handle between all functions that require it.
Signed-off-by: Ayush Singh <ayush@beagleboard.org>
Rollup of 3 pull requests
Successful merges:
- #126207 (std::unix::stack_overflow::drop_handler addressing todo through libc …)
- #131864 (Never emit `vptr` for empty/auto traits)
- #131870 (compiletest: Store test collection context/state in two structs)
r? `@ghost`
`@rustbot` modify labels: rollup
Abstract the state type for futexes
In the same way that we expose `SmallAtomic` and `SmallPrimitive` to allow Windows to use a value other than an `AtomicU32` for its futex state, switch the primary futex state type from `AtomicU32` to `futex::Futex`. The `futex::Futex` type should be usable as an atomic value with underlying primitive type equal to `futex::Primitive`. (`SmallAtomic` is also renamed to `SmallFutex`).
This allows supporting the futex API on systems where the underlying kernel futex implementation requires more user state than simply an `AtomicU32`.
All in-tree futex implementations simply define {`Futex`,`Primitive`} directly as {`AtomicU32`,`u32`}.
Avoid use imports in `thread_local_inner!`
Previously, the use imports in `thread_local_inner!` can shadow user-provided types or type aliases of the names `Storage`, `EagerStorage`, `LocalStorage` and `LocalKey`. This PR fixes that by dropping the use imports and instead refer to the std-internal types via fully qualified paths. A basic test is added to ensure `thread_local!`s with static decls with type names that match the aforementioned std-internal type names can successfully compile.
Fixes#131863.
Bump libc to 0.2.161
Bumps libc to the latest release version 0.2.161 which
- includes libc support for the tier 3 RTEMS target
- fixes segfaults on 32-bit FreeBSD targets
- gets musl's `posix_spawn_file_actions_addchdir_np` for some spawn opts
Various fixes for Xous
This patchset includes several fixes for Xous that have crept in over the last few months:
* The `adjust_process()` syscall was incorrect
* Warnings have started appearing in `alloc` -- adopt the same approach as wasm, until wasm figures out a workaround
* Dead code warnings have appeared in the networking code. Add `allow(dead_code)` as these structs are used as IPC values
* Add support for `args` and `env`, which have been useful for running tests
* Update `unwinding` to `0.2.3` which fixes the recent regression due to changes in `asm!()` code
In the same way that we expose SmallAtomic and SmallPrimitive to allow
Windows to use a value other than an AtomicU32 for its futex state, this
patch switches the primary futex state type from AtomicU32 to
futex::Atomic. The futex::Atomic type should be usable as an atomic
value with underlying primitive type equal to futex::Primitive.
This allows supporting the futex API on systems where the underlying
kernel futex implementation requires more state than simply an
AtomicU32.
All in-tree futex implementations simply define {Atomic,Primitive}
directly as {AtomicU32,u32}.
uefi: Implement getcwd and chdir
- Using EFI Shell Protocol. These functions do not make much sense unless a shell is present.
- Return the exe dir in case shell protocol is missing.
r? `@joboet`
Some float methods are now `const fn` under the `const_float_methods` feature gate.
In order to support `min`, `max`, `abs` and `copysign`, the implementation of some intrinsics had to be moved from Miri to rustc_const_eval.
Autodiff Upstreaming - enzyme frontend
This is an upstream PR for the `autodiff` rustc_builtin_macro that is part of the autodiff feature.
For the full implementation, see: https://github.com/rust-lang/rust/pull/129175
**Content:**
It contains a new `#[autodiff(<args>)]` rustc_builtin_macro, as well as a `#[rustc_autodiff]` builtin attribute.
The autodiff macro is applied on function `f` and will expand to a second function `df` (name given by user).
It will add a dummy body to `df` to make sure it type-checks. The body will later be replaced by enzyme on llvm-ir level,
we therefore don't really care about the content. Most of the changes (700 from 1.2k) are in `compiler/rustc_builtin_macros/src/autodiff.rs`, which expand the macro. Nothing except expansion is implemented for now.
I have a fallback implementation for relevant functions in case that rustc should be build without autodiff support. The default for now will be off, although we want to flip it later (once everything landed) to on for nightly. For the sake of CI, I have flipped the defaults, I'll revert this before merging.
**Dummy function Body:**
The first line is an `inline_asm` nop to make inlining less likely (I have additional checks to prevent this in the middle end of rustc. If `f` gets inlined too early, we can't pass it to enzyme and thus can't differentiate it.
If `df` gets inlined too early, the call site will just compute this dummy code instead of the derivatives, a correctness issue. The following black_box lines make sure that none of the input arguments is getting optimized away before we replace the body.
**Motivation:**
The user facing autodiff macro can verify the user input. Then I write it as args to the rustc_attribute, so from here on I can know that these values should be sensible. A rustc_attribute also turned out to be quite nice to attach this information to the corresponding function and carry it till the backend.
This is also just an experiment, I expect to adjust the user facing autodiff macro based on user feedback, to improve usability.
As a simple example of what this will do, we can see this expansion:
From:
```
#[autodiff(df, Reverse, Duplicated, Const, Active)]
pub fn f1(x: &[f64], y: f64) -> f64 {
unimplemented!()
}
```
to
```
#[rustc_autodiff]
#[inline(never)]
pub fn f1(x: &[f64], y: f64) -> f64 {
::core::panicking::panic("not implemented")
}
#[rustc_autodiff(Reverse, Duplicated, Const, Active,)]
#[inline(never)]
pub fn df(x: &[f64], dx: &mut [f64], y: f64, dret: f64) -> f64 {
unsafe { asm!("NOP"); };
::core::hint::black_box(f1(x, y));
::core::hint::black_box((dx, dret));
::core::hint::black_box(f1(x, y))
}
```
I will add a few more tests once I figured out why rustc rebuilds every time I touch a test.
Tracking:
- https://github.com/rust-lang/rust/issues/124509
try-job: dist-x86_64-msvc
- Using EFI Shell Protocol. These functions do not make much sense
unless a shell is present.
- Return the exe dir in case shell protocol is missing.
Signed-off-by: Ayush Singh <ayush@beagleboard.org>
merge const_ipv4 / const_ipv6 feature gate into 'ip' feature gate
https://github.com/rust-lang/rust/issues/76205 has been closed a while ago, but there are still some functions that reference it. Those functions are all unstable *and* const-unstable. There's no good reason to use a separate feature gate for their const-stability, so this PR moves their const-stability under the same gate as their regular stability, and therefore removes the remaining references to https://github.com/rust-lang/rust/issues/76205.
std::fs::get_path freebsd update.
what matters is we re doing the right things as doing sizeof, rather than passing KINFO_FILE_SIZE (only defined on intel architectures), the kernel
making sure it matches the expectation in its side.
The allocator on Xous is now throwing warnings because the allocator
needs to be mutable, and allocators hand out mutable pointers, which
the `static_mut_refs` lint now catches.
Give the same treatment to Xous as wasm, at least until a solution is
devised for fixing the warning on wasm.
Signed-off-by: Sean Cross <sean@xobs.io>
Process arguments and environment variables are both passed by way of
Application Parameters. These are a TLV format that gets passed in as
the second process argument.
This patch combines both as they are very similar in their decode.
Signed-off-by: Sean Cross <sean@osdyne.com>
std: fix stdout-before-main
Fixes#130210.
Since #124881, `ReentrantLock` uses `ThreadId` to identify threads. This has the unfortunate consequence of breaking uses of `Stdout` before main: Locking the `ReentrantLock` that synchronizes the output will initialize the thread ID before the handle for the main thread is set in `rt::init`. But since that would overwrite the current thread ID, `thread::set_current` triggers an abort.
This PR fixes the problem by using the already initialized thread ID for constructing the main thread handle and allowing `set_current` calls that do not change the thread's ID.
Fixes#130210.
Since #124881, `ReentrantLock` uses `ThreadId` to identify threads. This has the unfortunate consequence of breaking uses of `Stdout` before main: Locking the `ReentrantLock` that synchronizes the output will initialize the thread ID before the handle for the main thread is set in `rt::init`. But since that would overwrite the current thread ID, `thread::set_current` triggers an abort.
This PR fixes the problem by using the already initialized thread ID for constructing the main thread handle and allowing `set_current` calls that do not change the thread's ID.
Migrate lib's `&Option<T>` into `Option<&T>`
Trying out my new lint https://github.com/rust-lang/rust-clippy/pull/13336 - according to the [video](https://www.youtube.com/watch?v=6c7pZYP_iIE), this could lead to some performance and memory optimizations.
Basic thoughts expressed in the video that seem to make sense:
* `&Option<T>` in an API breaks encapsulation:
* caller must own T and move it into an Option to call with it
* if returned, the owner must store it as Option<T> internally in order to return it
* Performance is subject to compiler optimization, but at the basics, `&Option<T>` points to memory that has `presence` flag + value, whereas `Option<&T>` by specification is always optimized to a single pointer.
LLVM 20 split out what used to be called b16b16 and correspond to aarch64
FEAT_SVE_B16B16 into sve-b16b16 and sme-b16b16.
Add sme-b16b16 as an explicit feature and update the codegen accordingly.
Decouple WASIp2 sockets from WasiFd
This is a follow up to #129638, decoupling WASIp2's socket implementation from WASIp1's `WasiFd` as discussed with `@alexcrichton.`
Quite a few trait implementations in `std::os::fd` rely on the fact that there is an additional layer of abstraction between `Socket` and `OwnedFd`. I thus had to add a thin `WasiSocket` wrapper struct that just "forwards" to `OwnedFd`. Alternatively, I could have added a lot of conditional compilation to `std::os::fd`, which feels even worse.
Since `WasiFd::sock_accept` is no longer accessible from `TcpListener` and since WASIp2 has proper support for accepting sockets through `Socket::accept`, the `std::os::wasi::net` module has been removed from WASIp2, which only contains a single `TcpListenerExt` trait with a `sock_accept` method as well as an implementation for `TcpListener`. Let me know if this is an acceptable solution.
Android: Debug assertion after setting thread name
While `prctl` cannot fail if it points to a valid buffer, it's still better to assert the result as it's done for other places.
std: replace `LazyBox` with `OnceBox`
This PR replaces the `LazyBox` wrapper used to allocate the pthread primitives with `OnceBox`, which has a more familiar API mirroring that of `OnceLock`. This cleans up the code in preparation for larger changes like #128184 (from which this PR was split) and allows some neat optimizations, like avoid an acquire-load of the allocation pointer in `Mutex::unlock`, where the initialization of the allocation must have already been observed.
Additionally, I've gotten rid of the TEEOS `Condvar` code, it's just a duplicate of the pthread one anyway and I didn't want to repeat myself.
what matters is we re doing the right things as doing sizeof, rather than
KINFO_FILE_SIZE (only defined on intel architectures), the kernel
making sure it matches the expectation in its side.
Add `get_line` confusable to `Stdin::read_line()`
This pull request resolves https://github.com/rust-lang/rust/issues/131091
---
I've updated tests for `tests/ui/attributes/rustc_confusables_std_cases` in order to verify this change is working as intended.
Before I submitted this pull request, I had a pull request to my local fork. If you're interested in seeing the conversation on that PR, go to https://github.com/JakenHerman/rust/pull/1.
---
**Testing**:
Run `./x.py test tests/ui/attributes/rustc_confusables_std_cases.rs`
impl `Default` for `HashMap`/`HashSet` iterators that don't already have it
This is a follow-up to #128261 that isn't included in that PR because it depends on:
* [x] rust-lang/hashbrown#542 (`Default`)
* [x] `hashbrown` release containing above
It also wasn't included in #128261 initially and should have its own FCP, since these are also insta-stable.
Changes added:
* `Default for hash_map::{Iter, IterMut, IntoIter, IntoKeys, IntoValues, Keys, Values, ValuesMut}`
* `Default for hash_set::{Iter, IntoIter}`
Changes that were added before FCP, but are being deferred to later:
* `Clone for hash_map::{IntoIter, IntoKeys, IntoValues} where K: Clone, V: Clone`
* `Clone for hash_set::IntoIter where K: Clone`
std: make `thread::current` available in all `thread_local!` destructors
... and thereby allow the panic runtime to always print the right thread name.
This works by modifying the TLS destructor system to schedule a runtime cleanup function after all other TLS destructors registered by `std` have run. Unfortunately, this doesn't affect foreign TLS destructors, `thread::current` will still panic there.
Additionally, the thread ID returned by `current_id` will now always be available, even inside the global allocator, and will not change during the lifetime of one thread (this was previously the case with key-based TLS).
The mechanisms I added for this (`local_pointer` and `thread_cleanup`) will also allow finally fixing #111272 by moving the signal stack to a similar runtime-cleanup TLS variable.
Update hashbrown to 0.15 and adjust some methods
This PR updates `hashbrown` to 0.15 in the standard library and adjust some methods as well as removing some as they no longer exists in Hashbrown it-self.
- `HashMap::get_many_mut` change API to return array-of-Option
- `HashMap::{replace_entry, replace_key}` are removed, FCP close [already finished](https://github.com/rust-lang/rust/issues/44286#issuecomment-2293825619)
- `HashSet::get_or_insert_owned` is removed as it no longer exists in hashbrown
Closes https://github.com/rust-lang/rust/issues/44286
r? `@Amanieu`
This PR replaces the `LazyBox` wrapper used to allocate the pthread primitives with `OnceBox`, which has a more familiar API mirroring that of `OnceLock`. This cleans up the code in preparation for larger changes like #128184 (from which this PR was split) and allows some neat optimizations, like avoid an acquire-load of the allocation pointer in `Mutex::unlock`, where the initialization of the allocation must have already been observed.
Additionally, I've gotten rid of the TEEOS `Condvar` code, it's just a duplicate of the pthread one anyway and I didn't want to repeat myself.
Rollup of 5 pull requests
Successful merges:
- #130630 (Support clobber_abi and vector/access registers (clobber-only) in s390x inline assembly)
- #131042 (Instantiate binders in `supertrait_vtable_slot`)
- #131079 (Update wasm-component-ld to 0.5.9)
- #131085 (make test_lots_of_insertions test take less long in Miri)
- #131088 (add fixme to remove LLVM_ENABLE_TERMINFO when minimal llvm version is 19)
r? `@ghost`
`@rustbot` modify labels: rollup
make test_lots_of_insertions test take less long in Miri
This is by far the slowest `std` test in Miri, taking >2min in https://github.com/rust-lang/miri-test-libstd CI. So let's make this `count` smaller. The runtime should be quadratic in `count` so reducing it to around 2/3 of it's previous value should cut the total time down to less than half -- making it still the slowest test, but by less of a margin. (And this way we still insert >64 elements into the HashMap, in case that power of 2 matters.)
There is a MinGW ABI bug that prevents `f16` and `f128` from being
usable on `windows-gnu` targets. This does not affect MSVC; however, we
have `f16` and `f128` tests disabled on all Windows targets.
Update the gating to only affect `windows-gnu`, which means `f16` tests
will be enabled. There is no effect for `f128` since the default
fallback is `false`.
Enable `f16` tests on x86 Apple platforms
These were disabled because Apple uses a special ABI for `f16`. `compiler-builtins` merged a fix for this in [1], which has since propagated to rust-lang/rust. Enable tests since there should be no remaining issues on these platforms.
[1]: https://github.com/rust-lang/compiler-builtins/pull/675
try-job: x86_64-apple-1
try-job: x86_64-apple-2
Mark some more types as having insignificant dtor
These were caught by https://github.com/rust-lang/rust/pull/129864#issuecomment-2376658407, which is implementing a lint for some changes in drop order for temporaries in tail expressions.
Specifically, the destructors of `CString` and the bitpacked repr for `std::io::Error` are insignificant insofar as they don't have side-effects on things like locking or synchronization; they just free memory.
See some discussion on #89144 for what makes a drop impl "significant"
Hook up std::net to wasi-libc on wasm32-wasip2 target
One of the improvements of the `wasm32-wasip2` target over `wasm32-wasip1` is better support for networking. Right now, p2 is just re-using the `std::net` implementation from p1. This PR adds a new net module for p2 that makes use of net from `sys_common` and calls wasi-libc functions directly.
There are currently a few limitations:
- Duplicating a socket is not supported by WASIp2 (directly returns an error)
- Peeking is not yet implemented in wasi-libc (we could let wasi-libc handle this, but I opted to directly return an error instead)
- Vectored reads/writes are not supported by WASIp2 (the necessary functions are available in wasi-libc, but they call WASIp1 functions which do not support sockets, so I opted to directly return an error instead)
- Getting/setting `TCP_NODELAY` is faked in wasi-libc (uses the fake implementation instead of returning an error)
- Getting/setting `SO_LINGER` is not supported by WASIp2 (directly returns an error)
- Setting `SO_REUSEADDR` is faked in wasi-libc (since this is done from `sys_common`, the fake implementation is used instead of returning an error)
- Getting/setting `IPV6_V6ONLY` is not supported by WASIp2 and will always be set for IPv6 sockets (since this is done from `sys_common`, wasi-libc will return an error)
- UDP broadcast/multicast is not supported by WASIp2 (since this is configured from `sys_common`, wasi-libc will return appropriate errors)
- The `MSG_NOSIGNAL` send flag is a no-op because there are no signals in WASIp2 (since explicitly setting this flag would require a change to `sys_common` and the result would be exactly the same, I opted to not set it)
Do those decisions make sense?
While working on this PR, I noticed that there is a `std::os::wasi::net::TcpListenerExt` trait that adds a `sock_accept()` method to `std::net::TcpListener`. Now that WASIp2 supports standard accept, would it make sense to remove this?
cc `@alexcrichton`
Windows 10 1601 introduced `FileRenameInfoEx` as well as
`FILE_RENAME_FLAG_POSIX_SEMANTICS`, allowing for atomic renaming. If it
isn't supported, we fall back to `FileRenameInfo`.
This commit also replicates `MoveFileExW`'s behavior of checking whether
the source file is a mount point and moving the mount point instead of
resolving the target path.
Clarifications for set_nonblocking methods
Closes#129903.
The issue mentions that `send`, `recv` and other operations are interpreted by some users as methods of `TcpSocket` which led to confusion since it hasn't them. To fix it I added "system" into the documentation as being more precise for two reasons:
* it's makes it clear that these names are system operations;
* it doesn't point to the location of these methods like `libc` because not every system is POSIX compatible.
Update `catch_unwind` doc comments for `c_unwind`
Updates `catch_unwind` doc comments to indicate that catching a foreign exception _will no longer_ be UB. Instead, there are two possible behaviors, though it is not specified which one an implementation will choose.
Nominated for t-lang to confirm that they are okay with making such a promise based on t-opsem FCP, or whether they would like to be included in the FCP.
Related: https://github.com/rust-lang/rust/issues/74990, https://github.com/rust-lang/rust/issues/115285, https://github.com/rust-lang/reference/pull/1226
These were disabled because Apple uses a special ABI for `f16`.
`compiler-builtins` merged a fix for this in [1], which has since
propagated to rust-lang/rust. Enable tests since there should be no
remaining issues on these platforms.
[1]: https://github.com/rust-lang/compiler-builtins/pull/675
Enable `f16` tests on platforms that were missing conversion symbols
The only requirement for `f16` support, aside from LLVM not crashing and no ABI issues, is that symbols to convert to and from `f32` are available. Since the update to compiler-builtins in https://github.com/rust-lang/rust/pull/125016, we now provide these on all platforms.
This also enables `f16` math since there are no further requirements.
Still excluded are platforms for which LLVM emits infinitely-recursing code.
try-job: arm-android
try-job: test-various
try-job: x86_64-fuchsia
The only requirement for `f16` support, aside from LLVM not crashing and
no ABI issues, is that symbols to convert to and from `f32` are
available. Since the update to compiler-builtins in [1], we now provide
these on all platforms.
This also enables `f16` math since there are no further requirements.
Still excluded are platforms for which LLVM emits infinitely-recursing
code.
[1]: https://github.com/rust-lang/rust/pull/125016
update `compiler-builtins` to 0.1.126
this requires the addition of a bootstrap variant of the new `naked_asm!` macro
r? `@tgross35`
extracted from https://github.com/rust-lang/rust/pull/128651
Revert Break into the debugger on panic (129019)
This was talked about a bit at a recent libs meeting. While I think experimenting with this is worthwhile, I am nervous about this new behaviour reaching stable. We've already reverted on one tier 1 platform (Linux, https://github.com/rust-lang/rust/pull/130810) which means we have differing semantics on different tier 1 platforms. Also the fact it triggers even when `catch_unwind` is used to catch the panic means it can be very noisy in some projects.
At the very least I think it could use some more discussion before being instantly stable. I think this could maybe be re-landed with an environment variable to control/override the behaviour. But that part would likely need a libs-api decision.
cc ````@workingjubilee```` ````@kromych````
Since the stabilization in #127679 has reached stage0, 1.82-beta, we can
start using `&raw` freely, and even the soft-deprecated `ptr::addr_of!`
and `ptr::addr_of_mut!` can stop allowing the unstable feature.
I intentionally did not change any documentation or tests, but the rest
of those macro uses are all now using `&raw const` or `&raw mut` in the
standard library.
Rollup of 6 pull requests
Successful merges:
- #130549 (Add RISC-V vxworks targets)
- #130595 (Initial std library support for NuttX)
- #130734 (Fix: ices on virtual-function-elimination about principal trait)
- #130787 (Ban combination of GCE and new solver)
- #130809 (Update llvm triple for OpenHarmony targets)
- #130810 (Don't trap into the debugger on panics under Linux)
r? `@ghost`
`@rustbot` modify labels: rollup
Initial std library support for NuttX
This PR add the initial libstd support for NuttX platform (Tier 3), currently it depends on https://github.com/rust-lang/libc/pull/3909 which provide the essential libc definitions.
Add `File` constructors that return files wrapped with a buffer
In addition to the light convenience, these are intended to raise visibility that buffering is something you should consider when opening a file, since unbuffered I/O is a common performance footgun to Rust newcomers.
ACP: https://github.com/rust-lang/libs-team/issues/446
Tracking Issue: #130804
The latest versions of `memchr` experience LTO-related issues when
compiling for windows-gnu [1], so needs to be pinned. The issue is
present in the standard library.
`memchr` has been pinned in `rustc_ast`, but since the workspace was
recently split, this pin no longer has any effect on library crates.
Resolve this by adding `memchr` as an _unused_ dependency in `std`,
pinned to 2.5. Additionally, remove the pin in `rustc_ast` to allow
non-library crates to upgrade to the latest version.
Link: https://github.com/rust-lang/rust/issues/127890 [1]
Add test for `available_parallelism()`
This is a redo of [this PR](https://github.com/rust-lang/rust/pull/104095).
I changed the location of the test as per comments in the original thread. Otherwise the test is practically the same.
try-job: test-various
Remove macOS 10.10 dynamic linker bug workaround
Rust's current minimum macOS version is 10.12, so the hack can be removed. This PR also updates the `remove_dir_all` docs to reflect that all supported macOS versions are protected against TOCTOU race conditions (the fallback implementation was already removed in #127683).
try-job: dist-x86_64-apple
try-job: dist-aarch64-apple
try-job: dist-apple-various
try-job: aarch64-apple
try-job: x86_64-apple-1
`pal::unsupported::process::ExitCode`: use an `u8` instead of a `bool`
`ExitCode` should “represents the status code the current process can return to its parent under normal termination”, but is currently represented as a `bool` on unsupported platforms, making the `impl From<u8> for ExitCode` lossy.
Fixes#130532.
History: [IRLO thread](https://internals.rust-lang.org/t/mini-pre-rfc-redesigning-process-exitstatus/5426) (`ExitCode` as a `main` return), #48618 (initial impl), #93445 (`From<u8>` impl).
Win: Open dir for sync access in remove_dir_all
A small follow up to #129800.
We should explicitly open directories for synchronous access. We ultimately use `GetFileInformationByHandleEx` to read directories which should paper over any issues caused by using async directory reads (or else return an error) but it's better to do the right thing in the first place. Note though that `delete` does not read or write any data so it's not necessary there.
In the implementation of `force_mut`, I chose performance over safety.
For `LazyLock` this isn't really a choice; the code has to be unsafe.
But for `LazyCell`, we can have a full-safe implementation, but it will
be a bit less performant, so I went with the unsafe approach.
fix: Remove duplicate `LazyLock` example.
The top-level docs for `LazyLock` included two lines of code, each with an accompanying comment, that were identical and with nearly- identical comments. This looks like an oversight from a past edit which was perhaps trying to rewrite an existing example but ended up duplicating rather than replacing, though I haven't gone back through the Git history to check.
This commit removes what I personally think is the less-clear of the two examples.
[library/std/src/process.rs] `PartialEq` for `ExitCode`
Converting a third-party CLI to a library so started passing around [`std::process::ExitCode`](https://doc.rust-lang.org/std/process/struct.ExitCode.html) in an `Either`. Then I realised the tests can't be modified to compare equality of `ExitCode`s.
This PR fixes this oversight.
The top-level docs for `LazyLock` included two lines of code, each
with an accompanying comment, that were identical and with nearly-
identical comments. This looks like an oversight from a past edit
which was perhaps trying to rewrite an existing example but ended
up duplicating rather than replacing, though I haven't gone back
through the Git history to check.
This commit removes what I personally think is the less-clear of
the two examples.
Signed-off-by: Andrew Lilley Brinker <alilleybrinker@gmail.com>
Add `core::panic::abort_unwind`
`abort_unwind` is like `catch_unwind` except that it aborts the process if it unwinds, using the `#[rustc_nounwind]` mechanism also used by `extern "C" fn` to abort unwinding. The docs attempt to make it clear when to (rarely) and when not to (usually) use the function.
Although usage of the function is discouraged, having it available will help to normalize the experience when abort_unwind shims are hit, as opposed to the current ecosystem where there exist multiple common patterns for converting unwinding into a process abort.
For further information and justification, see the linked ACP.
- Tracking issue: https://github.com/rust-lang/rust/issues/130338
- ACP: https://github.com/rust-lang/libs-team/issues/441
Stabilize `&mut` (and `*mut`) as well as `&Cell` (and `*const Cell`) in const
This stabilizes `const_mut_refs` and `const_refs_to_cell`. That allows a bunch of new things in const contexts:
- Mentioning `&mut` types
- Creating `&mut` and `*mut` values
- Creating `&T` and `*const T` values where `T` contains interior mutability
- Dereferencing `&mut` and `*mut` values (both for reads and writes)
The same rules as at runtime apply: mutating immutable data is UB. This includes mutation through pointers derived from shared references; the following is diagnosed with a hard error:
```rust
#[allow(invalid_reference_casting)]
const _: () = {
let mut val = 15;
let ptr = &val as *const i32 as *mut i32;
unsafe { *ptr = 16; }
};
```
The main limitation that is enforced is that the final value of a const (or non-`mut` static) may not contain `&mut` values nor interior mutable `&` values. This is necessary because the memory those references point to becomes *read-only* when the constant is done computing, so (interior) mutable references to such memory would be pretty dangerous. We take a multi-layered approach here to ensuring no mutable references escape the initializer expression:
- A static analysis rejects (interior) mutable references when the referee looks like it may outlive the current MIR body.
- To be extra sure, this static check is complemented by a "safety net" of dynamic checks. ("Dynamic" in the sense of "running during/after const-evaluation, e.g. at runtime of this code" -- in contrast to "static" which works entirely by looking at the MIR without evaluating it.)
- After the final value is computed, we do a type-driven traversal of the entire value, and if we find any `&mut` or interior-mutable `&` we error out.
- However, the type-driven traversal cannot traverse `union` or raw pointers, so there is a second dynamic check where if the final value of the const contains any pointer that was not derived from a shared reference, we complain. This is currently a future-compat lint, but will become an ICE in #128543. On the off-chance that it's actually possible to trigger this lint on stable, I'd prefer if we could make it an ICE before stabilizing const_mut_refs, but it's not a hard blocker. This part of the "safety net" is only active for mutable references since with shared references, it has false positives.
Altogether this should prevent people from leaking (interior) mutable references out of the const initializer.
While updating the tests I learned that surprisingly, this code gets rejected:
```rust
const _: Vec<i32> = {
let mut x = Vec::<i32>::new(); //~ ERROR destructor of `Vec<i32>` cannot be evaluated at compile-time
let r = &mut x;
let y = x;
y
};
```
The analysis that rejects destructors in `const` is very conservative when it sees an `&mut` being created to `x`, and then considers `x` to be always live. See [here](https://github.com/rust-lang/rust/issues/65394#issuecomment-541499219) for a longer explanation. `const_precise_live_drops` will solve this, so I consider this problem to be tracked by https://github.com/rust-lang/rust/issues/73255.
Cc `@rust-lang/wg-const-eval` `@rust-lang/lang`
Cc https://github.com/rust-lang/rust/issues/57349
Cc https://github.com/rust-lang/rust/issues/80384
some const cleanup: remove unnecessary attributes, add const-hack indications
I learned that we use `FIXME(const-hack)` on top of the "const-hack" label. That seems much better since it marks the right place in the code and moves around with the code. So I went through the PRs with that label and added appropriate FIXMEs in the code. IMO this means we can then remove the label -- Cc ``@rust-lang/wg-const-eval.``
I also noticed some const stability attributes that don't do anything useful, and removed them.
r? ``@fee1-dead``
Expand documentation of PathBuf, discussing lack of sanitization
Various methods in `PathBuf`, in particular `set_file_name` and `set_extension` accept strings which include path seperators (like `../../etc`). These methods just glue together strings, so you can end up with strange strings.
This isn't reasonable to change/fix at this point, and might not even be fixable, but I think should be documented. In particular, you probably shouldn't blindly build paths using strings given by possibly malicious users.
Limit `libc::link` usage to `nto70` target only, not NTO OS
It seems QNX 7.0 does not support `linkat` at all (most tests were failing). Limiting to QNX 7.0 only, while using `linkat` for the future versions seems like the right path forward (tested on 7.0).
Fixes#129895
CC: `@japaric` `@flba-eb` `@saethlin`
enable const-float-classify test, and test_next_up/down on 32bit x86
The test_next_up/down tests have been disabled on all 32bit x86 targets, which goes too far -- they should definitely work on our (tier 1) i686 target, it is only without SSE that we might run into trouble due to https://github.com/rust-lang/rust/issues/114479. However, I cannot reproduce that trouble any more -- maybe that got fixed by https://github.com/rust-lang/rust/pull/123351?
The const-float-classify test relied on const traits "because we can", and got disabled when const traits got removed. That's an unfortunate reduction in test coverage of our float functionality, so let's restore the test in a way that does not rely on const traits.
The const-float tests are actually testing runtime behavior as well, and I don't think that runtime behavior is covered anywhere else. Probably they shouldn't be called "const-float", but we don't have a `tests/ui/float` folder... should I create one and move them there? Are there any other ui tests that should be moved there?
I also removed some FIXME referring to not use x87 for Rust-to-Rust-calls -- that has happened in #123351 so this got fixed indeed. Does that mean we can simplify all that float code again? I am not sure how to test it. Is running the test suite with an i586 target enough?
Cc ```@tgross35``` ```@workingjubilee```
It seems QNX 7.0 does not support `linkat` at all (most tests were failing). Limiting to QNX 7.0 only, while using `linkat` for the future versions seems like the right path forward (tested on 7.0).
Fixes 129895
Map `ERROR_CANT_RESOLVE_FILENAME` to `ErrorKind::FilesystemLoop`
cc #86442
As summarized in #130188, there seems to be a consensus that this should be done.
Clarify documentation labelling and definitions for std::collections
Page affected: https://doc.rust-lang.org/std/collections/index.html#performance
Changes:
- bulleted conventions
- expanded definitions on terms used
- more accessible language
- more informative headings
Also emit `missing_docs` lint with `--test` to fulfil expectations
This PR removes the "test harness" suppression of the `missing_docs` lint to be able to fulfil `#[expect]` (expectations) as it is now "relevant".
I think the goal was to maybe avoid false-positive while linting on public items under `#[cfg(test)]` but with effective visibility we should no longer have any false-positive.
Another possibility would be to query the lint level and only emit the lint if it's of expect level, but that is even more hacky.
Fixes https://github.com/rust-lang/rust/issues/130021
try-job: x86_64-gnu-aux
[illumos] enable SIGSEGV handler to detect stack overflows
Use the same code as Solaris. I couldn't find any tests regarding this, but I did test a stage0 build against my stack-exhaust-test binary [1]. Before:
```
running with use_stacker = No, new_thread = false, make_large_local = false
zsh: segmentation fault (core dumped) cargo run
```
After:
```
running with use_stacker = No, new_thread = false, make_large_local = false
thread 'main' has overflowed its stack
fatal runtime error: stack overflow
zsh: IOT instruction (core dumped) cargo +stage0 run
```
Fixes#128568.
[1] https://github.com/sunshowers/stack-exhaust-test/
Stabilize most of `io_error_more`
Sadly, venting my frustration with t-libs-api is not a constructive way to solve problems and get things done, so I will try to stick to stuff that actually matters here.
- Tracking issue for this feature was opened 3 years ago: #86442
- FCP to stabilize it was completed 19(!!) months ago: https://github.com/rust-lang/rust/issues/86442#issuecomment-1368082102
- A PR with stabilization was similarly open for 19 months: #106375, but nothing ever came out of it. Presumably (it is hard to judge given the lack of communication) because a few of the variants still had some concerns voiced about them, even after the FCP.
So, to highlight a common sentiment:
> Maybe uncontroversial variants can be stabilised first and other variants (such as `QuotaExceeded` or `FilesystemLoop`) later? [^1]
[^1]: https://github.com/rust-lang/rust/issues/106375#issuecomment-1435762236
> I would like to voice support stabilization of the uncontroversial variants. This would get those variants to stable and focus the discussion around the more controversial ones. I don't see any particular reason that all of these must be stabilized at the same time. [...] [^2]
[^2]: https://github.com/rust-lang/rust/pull/106375#issuecomment-1742661555
> Maybe some less-controversial subset could be stabilized sooner? What’s blocking this issue from making progress? [^3]
[^3]: https://github.com/rust-lang/rust/issues/86442#issuecomment-1691187483 (got 30 upvotes btw) (and no response)
So this is exactly what this PR does. It stabilizes the non-controversial variants now, leaving just a few of them behind.
Namely, this PR stabilizes:
- `HostUnreachable`
- `NetworkUnreachable`
- `NetworkDown`
- `NotADirectory`
- `IsADirectory`
- `DirectoryNotEmpty`
- `ReadOnlyFilesystem`
- `StaleNetworkFileHandle`
- `StorageFull`
- `NotSeekable`
- `FileTooLarge`
- `ResourceBusy`
- `ExecutableFileBusy`
- `Deadlock`
- `TooManyLinks`
- `ArgumentListTooLong`
- `Unsupported`
This PR does not stabilize:
- `FilesystemLoop`
- `FilesystemQuotaExceeded`
- `CrossesDevices`
- `InvalidFilename`
Hopefully, this will allow us to move forward with this highly and long awaited addition to std, both allowing to still polish the less clear parts of it and not leading to stagnation.
r? joshtriplett
because they seem to be listed as a part of t-libs-api and were one of the most responsive persons previously
Remove redundant check in `symlink_hard_link` test
We support macOS 10.12 and above, so it now always uses `linkat`, and so the check is redundant.
This was missed in #126351.
``@rustbot`` label O-macos
Use the same code as Solaris. I couldn't find any tests regarding this, but I
did test a stage0 build against my stack-exhaust-test binary [1]. Before:
```
running with use_stacker = No, new_thread = false, make_large_local = false
zsh: segmentation fault (core dumped) cargo run
```
After:
```
running with use_stacker = No, new_thread = false, make_large_local = false
thread 'main' has overflowed its stack
fatal runtime error: stack overflow
zsh: IOT instruction (core dumped) cargo +stage0 run
```
Fixes#128568.
[1] https://github.com/sunshowers/stack-exhaust-test/
Break into the debugger (if attached) on panics (Windows, Linux, macOS, FreeBSD)
The developer experience for panics is to provide the backtrace and
exit the program. When running under debugger, that might be improved
by breaking into the debugger once the code panics thus enabling
the developer to examine the program state at the exact time when
the code panicked.
Let the developer catch the panic in the debugger if it is attached.
If the debugger is not attached, nothing changes. Providing this feature
inside the standard library facilitates better debugging experience.
Validated under Windows, Linux, macOS 14.6, and FreeBSD 13.3..14.1.
In https://github.com/rust-lang/rust/pull/124748, I mistakenly conflated
"not SjLj" to mean "ARM EHABI", which isn't true, watchOS armv7k
(specifically only that architecture) uses a third unwinding method
called "DWARF CFI".
Inaccurate `{Path,OsStr}::to_string_lossy()` documentation
The documentation of `Path::to_string_lossy()` and `OsStr::to_string_lossy()` says the following:
> Any non-Unicode sequences are replaced with `U+FFFD REPLACEMENT CHARACTER`
which didn't immediately make sense to me. ("non-Unicode sequences"?)
Since both `to_string_lossy` functions eventually become just a call to `String::from_utf8_lossy`, I believe the documentation meant to say:
> Any *non-UTF-8* sequences are replaced with `U+FFFD REPLACEMENT CHARACTER`
This PR corrects this mistake in the documentation.
For the record, a similar quote can be found in the documentation of `String::from_utf8_lossy`:
> ... During this conversion, `from_utf8_lossy()` will replace any invalid UTF-8 sequences with `U+FFFD REPLACEMENT CHARACTER`, ...
The developer experience for panics is to provide the backtrace and
exit the program. When running under debugger, that might be improved
by breaking into the debugger once the code panics thus enabling
the developer to examine the program state at the exact time when
the code panicked.
Let the developer catch the panic in the debugger if it is attached.
If the debugger is not attached, nothing changes. Providing this feature
inside the standard library facilitates better debugging experience.
Validated under Windows, Linux, macOS 14.6, and FreeBSD 13.3..14.1.
Add target support for RTEMS Arm
# `armv7-rtems-eabihf`
This PR adds a new target for the RTEMS RTOS. To get things started it focuses on Xilinx/AMD Zynq-based targets, but in theory it should also support other armv7-based board support packages in the future.
Given that RTEMS has support for many POSIX functions it is mostly enabling corresponding unix features for the new target.
I also previously started a PR in libc (https://github.com/rust-lang/libc/pull/3561) to add the needed OS specific C-bindings and was told that a PR in this repo is needed first. I will update the PR to the newest version after approval here.
I will probably also need to change one line in the backtrace repo.
Current status is that I could compile rustc for the new target locally (with the updated libc and backtrace) and could compile binaries, link, and execute a simple "Hello World" RTEMS application for the target hardware.
> A proposed target or target-specific patch that substantially changes code shared with other targets (not just target-specific code) must be reviewed and approved by the appropriate team for that shared code before acceptance.
There should be no breaking changes for existing targets. Main changes are adding corresponding `cfg` switches for the RTEMS OS and adding the C binding in libc.
# Tier 3 target policy
> - A tier 3 target must have a designated developer or developers (the "target maintainers") on record to be CCed when issues arise regarding the target. (The mechanism to track and CC such developers may evolve over time.)
I will do the maintenance (for now) further members of the RTEMS community will most likely join once the first steps have been done.
> - Targets must use naming consistent with any existing targets; for instance, a target for the same CPU or OS as an existing Rust target should use the same name for that CPU or OS. Targets should normally use the same names and naming conventions as used elsewhere in the broader ecosystem beyond Rust (such as in other toolchains), unless they have a very good reason to diverge. Changing the name of a target can be highly disruptive, especially once the target reaches a higher tier, so getting the name right is important even for a tier 3 target.
> - Target names should not introduce undue confusion or ambiguity unless absolutely necessary to maintain ecosystem compatibility. For example, if the name of the target makes people extremely likely to form incorrect beliefs about what it targets, the name should be changed or augmented to disambiguate it.
> - If possible, use only letters, numbers, dashes and underscores for the name. Periods (`.`) are known to cause issues in Cargo.
The proposed triple is `armv7-rtems-eabihf`
> - Tier 3 targets may have unusual requirements to build or use, but must not create legal issues or impose onerous legal terms for the Rust project or for Rust developers or users.
> - The target must not introduce license incompatibilities.
> - Anything added to the Rust repository must be under the standard Rust license (`MIT OR Apache-2.0`).
> - The target must not cause the Rust tools or libraries built for any other host (even when supporting cross-compilation to the target) to depend on any new dependency less permissive than the Rust licensing policy. This applies whether the dependency is a Rust crate that would require adding new license exceptions (as specified by the `tidy` tool in the rust-lang/rust repository), or whether the dependency is a native library or binary. In other words, the introduction of the target must not cause a user installing or running a version of Rust or the Rust tools to be subject to any new license requirements.
> - Compiling, linking, and emitting functional binaries, libraries, or other code for the target (whether hosted on the target itself or cross-compiling from another target) must not depend on proprietary (non-FOSS) libraries. Host tools built for the target itself may depend on the ordinary runtime libraries supplied by the platform and commonly used by other applications built for the target, but those libraries must not be required for code generation for the target; cross-compilation to the target must not require such libraries at all. For instance, `rustc` built for the target may depend on a common proprietary C runtime library or console output library, but must not depend on a proprietary code generation library or code optimization library. Rust's license permits such combinations, but the Rust project has no interest in maintaining such combinations within the scope of Rust itself, even at tier 3.
> - "onerous" here is an intentionally subjective term. At a minimum, "onerous" legal/licensing terms include but are _not_ limited to: non-disclosure requirements, non-compete requirements, contributor license agreements (CLAs) or equivalent, "non-commercial"/"research-only"/etc terms, requirements conditional on the employer or employment of any particular Rust developers, revocable terms, any requirements that create liability for the Rust project or its developers or users, or any requirements that adversely affect the livelihood or prospects of the Rust project or its developers or users.
The tools consists of the cross-compiler toolchain (gcc-based). The RTEMS kernel (BSD license) and parts of the driver stack of FreeBSD (BSD license). All tools are FOSS and publicly available here: https://gitlab.rtems.org/rtems
There are also no new features or dependencies introduced to the Rust code.
> - Neither this policy nor any decisions made regarding targets shall create any binding agreement or estoppel by any party. If any member of an approving Rust team serves as one of the maintainers of a target, or has any legal or employment requirement (explicit or implicit) that might affect their decisions regarding a target, they must recuse themselves from any approval decisions regarding the target's tier status, though they may otherwise participate in discussions.
N/A to me. I am not a reviewer nor Rust team member.
> - Tier 3 targets should attempt to implement as much of the standard libraries as possible and appropriate (`core` for most targets, `alloc` for targets that can support dynamic memory allocation, `std` for targets with an operating system or equivalent layer of system-provided functionality), but may leave some code unimplemented (either unavailable or stubbed out as appropriate), whether because the target makes it impossible to implement or challenging to implement. The authors of pull requests are not obligated to avoid calling any portions of the standard library on the basis of a tier 3 target not implementing those portions.
`core` and `std` compile. Some advanced features of the `std` lib might not work yet. However, the goal of this tier 3 target it to make it easier for other people to build and run test applications to better identify the unsupported features and work towards enabling them.
> - The target must provide documentation for the Rust community explaining how to build for the target, using cross-compilation if possible. If the target supports running binaries, or running tests (even if they do not pass), the documentation must explain how to run such binaries or tests for the target, using emulation if possible or dedicated hardware if necessary.
Building is described in platform support doc. Running simple unit tests works. Running the test suite of the stdlib is currently not that easy. Trying to work towards that after the this target has been added to the nightly.
> - Tier 3 targets must not impose burden on the authors of pull requests, or other developers in the community, to maintain the target. In particular, do not post comments (automated or manual) on a PR that derail or suggest a block on the PR based on a tier 3 target. Do not send automated messages or notifications (via any medium, including via ````@`)``` to a PR author or others involved with a PR regarding a tier 3 target, unless they have opted into such messages.
Understood.
> - Backlinks such as those generated by the issue/PR tracker when linking to an issue or PR are not considered a violation of this policy, within reason. However, such messages (even on a separate repository) must not generate notifications to anyone involved with a PR who has not requested such notifications.
Ok
> - Patches adding or updating tier 3 targets must not break any existing tier 2 or tier 1 target, and must not knowingly break another tier 3 target without approval of either the compiler team or the maintainers of the other tier 3 target.
> - In particular, this may come up when working on closely related targets, such as variations of the same architecture with different features. Avoid introducing unconditional uses of features that another variation of the target may not have; use conditional compilation or runtime detection, as appropriate, to let each target run code supported by that target.
I think, I didn't add any breaking changes for any existing targets (see the comment regarding features above).
> - Tier 3 targets must be able to produce assembly using at least one of rustc's supported backends from any host target.
Can produce assembly code via the llvm backend (tested on Linux).
>
> If a tier 3 target stops meeting these requirements, or the target maintainers no longer have interest or time, or the target shows no signs of activity and has not built for some time, or removing the target would improve the quality of the Rust codebase, we may post a PR to remove it; any such PR will be CCed to the target maintainers (and potentially other people who have previously worked on the target), to check potential interest in improving the situation.GIAt this tier, the Rust project provides no official support for a target, so we place minimal requirements on the introduction of targets.
Understood.
r? compiler-team
Add missing read_buf stub for x86_64-unknown-l4re-uclibc
Before this PR, `x check library/std --target x86_64-unknown-l4re-uclibc` will fail with
```
error[E0599]: no method named `read_buf` found for struct `Socket` in the current scope
--> std/src/os/unix/net/stream.rs:598:16
|
598 | self.0.read_buf(buf)
| ^^^^^^^^
|
::: std/src/sys/pal/unix/l4re.rs:23:5
|
23 | pub struct Socket(FileDesc);
| ----------------- method `read_buf` not found for this struct
|
= help: items from traits can only be used if the trait is implemented and in scope
```
This target doesn't have a maintainer to cc.
Move the Windows remove_dir_all impl into a module and make it more race resistant
This attempts to make the Windows implementation of `remove_dir_all` easier to understand and work with by separating out different concerns into their own functions. The code is mostly the same as before just moved around. There are some changes to make it more robust against races (e.g. two calls to `remove_dir_all` running concurrently). The module level comment explains the issue.
try-job: x86_64-msvc
try-job: i686-msvc
Fix compile error in solid's remove_dir_all
Before this PR, `x check library/std --target=aarch64-kmc-solid_asp3` will fail with:
```
error[E0382]: use of partially moved value: `result`
--> std/src/sys/pal/solid/fs.rs:544:20
|
541 | if let Err(err) = result
| --- value partially moved here
...
544 | return result;
| ^^^^^^ value used here after partial move
|
= note: partial move occurs because value has type `io::error::Error`, which does not implement the `Copy` trait
help: borrow this binding in the pattern to avoid moving the value
|
541 | if let Err(ref err) = result
| +++
```
cc `@kawadakk` I think this will clear up https://solid-rs.github.io/toolstate/ :)
Rollup of 9 pull requests
Successful merges:
- #127474 (doc: Make block of inline Deref methods foldable)
- #129678 (Deny imports of `rustc_type_ir::inherent` outside of type ir + new trait solver)
- #129738 (`rustc_mir_transform` cleanups)
- #129793 (add extra linebreaks so rustdoc can identify the first sentence)
- #129804 (Fixed some typos in the standard library documentation/comments)
- #129837 (Actually parse stdout json, instead of using hacky contains logic.)
- #129842 (Fix LLVM ABI NAME for riscv64imac-unknown-nuttx-elf)
- #129843 (Mark myself as on vacation for triagebot)
- #129858 (Replace walk with visit so we dont skip outermost expr kind in def collector)
Failed merges:
- #129777 (Add `unreachable_pub`, round 4)
- #129868 (Remove kobzol vacation status)
r? `@ghost`
`@rustbot` modify labels: rollup
Apply size optimizations to panic machinery and some cold functions
* std dependencies gimli and addr2line are now built with opt-level=s
* various panic-related methods and `#[cold]` methods are now marked `#[optimize(size)]`
Panics should be cold enough that it doesn't make sense to optimize them for speed. The only tradeoff here is if someone does a lot of backtrace captures (without panics) and printing then the opt-level change might impact their perf.
Seems to be the first use of the optimize attribute. Tracking issue #54882
add `aarch64_unknown_nto_qnx700` target - QNX 7.0 support for aarch64le
This backports the QNX 7.1 aarch64 implementation to 7.0.
* [x] required `-lregex` disabled, see https://github.com/rust-lang/libc/pull/3775 (released in libc 0.2.156)
* [x] uses `libgcc.a` instead of `libgcc_s.so` (7.0 used ancient GCC 5.4 which didn't have gcc_s)
* [x] a fix in `backtrace` crate to support stack traces https://github.com/rust-lang/backtrace-rs/pull/648
This PR bumps libc dependency to 0.2.158
CC: to the folks who did the [initial implementation](https://doc.rust-lang.org/rustc/platform-support/nto-qnx.html): `@flba-eb,` `@gh-tr,` `@jonathanpallant,` `@japaric`
# Compile target
```bash
# Configure qcc build environment
source _path_/_to_/qnx7.0/qnxsdp-env.sh
# Tell rust to use qcc when building QNX 7.0 targets
export build_env='
CC_aarch64-unknown-nto-qnx700=qcc
CFLAGS_aarch64-unknown-nto-qnx700=-Vgcc_ntoaarch64le_cxx
CXX_aarch64-unknown-nto-qnx700=qcc
AR_aarch64_unknown_nto_qnx700=ntoaarch64-ar'
# Build rust compiler, libs, and the remote test server
env $build_env ./x.py build \
--target x86_64-unknown-linux-gnu,aarch64-unknown-nto-qnx700 \
rustc library/core library/alloc library/std src/tools/remote-test-server
rustup toolchain link stage1 build/host/stage1
```
# Compile "hello world"
```bash
source _path_/_to_/qnx7.0/qnxsdp-env.sh
cargo new hello_world
cd hello_world
cargo +stage1 build --release --target aarch64-unknown-nto-qnx700
```
# Configure a remote for testing
Do this from a new shell - we will need to run more commands in the previous one. I ran into these two issues, and found some workarounds.
* Temporary dir might not work properly
* Default `remote-test-server` has issues binding to an address
```
# ./remote-test-server
starting test server
thread 'main' panicked at src/tools/remote-test-server/src/main.rs:175:29:
called `Result::unwrap()` on an `Err` value: Os { code: 249, kind: AddrNotAvailable, message: "Can't assign requested address" }
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
```
Specifying `--bind` param actually fixes that, and so does setting `TMPDIR` properly.
```bash
# Copy remote-test-server to remote device. You may need to use sftp instead.
# ATTENTION: Note that the path is different from the one in the remote testing documentation for some reason
scp ./build/x86_64-unknown-linux-gnu/stage1-tools-bin/remote-test-server qnxdevice:/path/
# Run ssh with port forwarding - so that rust tester can connect to the local port instead
ssh -L 12345:127.0.0.1:12345 qnxdevice
# on the device, run
rm -rf tmp && mkdir -p tmp && TMPDIR=$PWD/tmp ./remote-test-server --bind 0.0.0.0:12345
```
# Run test suit
Assume all previous environment variables are still set, or re-init them
```bash
export TEST_DEVICE_ADDR="localhost:12345"
# tidy needs to be skipped due to using un-published libc dependency
export exclude_tests='
--exclude src/bootstrap
--exclude src/tools/error_index_generator
--exclude src/tools/linkchecker
--exclude src/tools/tidy
--exclude tests/ui-fulldeps
--exclude rustc
--exclude rustdoc
--exclude tests/run-make-fulldeps'
env $build_env ./x.py test $exclude_tests --stage 1 --target aarch64-unknown-nto-qnx700
```
try-job: dist-x86_64-msvc
wasi: Fix sleeping for `Duration::MAX`
This commit fixes an assert in the WASI-specific implementation of thread sleep to ensure that sleeping for a very large period of time blocks instead of panicking. This can come up when testing programs that sleep "forever", for example.
I'll note that I haven't included a test for this since it's sort of difficult to test. I've tested this locally though that long sleeps do indeed block and short sleeps still only sleep for a short amount of time.
This commit fixes an assert in the WASI-specific implementation of
thread sleep to ensure that sleeping for a very large period of time
blocks instead of panicking. This can come up when testing programs that
sleep "forever", for example.
copysign with sign being a NaN can have non-portable results
Follow-up to https://github.com/rust-lang/rust/pull/129559.
Cc ```@tgross35``` ```@beetrees```
There's no portable variant we can recommend instead here, is there? Something with a semantics like "if `sign` is a NaN, then return `self` unaltered, otherwise return `self` with the sign changed to that of `sign`"?
Clean up cfg-gating of ProcessPrng extern
This removes a bit of duplication and is consistent with how `api-ms-win-core-synch-l1-2-0` externs are imported.
rustc_target: Add various aarch64 features
Add various aarch64 features already supported by LLVM and Linux.
Additionally include some comment fixes to ensure consistency of feature names with the Arm ARM.
Compiler support for features added to stdarch by https://github.com/rust-lang/stdarch/pull/1614.
Tracking issue for unstable aarch64 features is https://github.com/rust-lang/rust/issues/127764.
List of added features:
- FEAT_CSSC
- FEAT_ECV
- FEAT_FAMINMAX
- FEAT_FLAGM2
- FEAT_FP8
- FEAT_FP8DOT2
- FEAT_FP8DOT4
- FEAT_FP8FMA
- FEAT_HBC
- FEAT_LSE128
- FEAT_LSE2
- FEAT_LUT
- FEAT_MOPS
- FEAT_LRCPC3
- FEAT_SVE_B16B16
- FEAT_SVE2p1
- FEAT_WFxT
- FEAT_SME
- FEAT_SME_F16F16
- FEAT_SME_F64F64
- FEAT_SME_F8F16
- FEAT_SME_F8F32
- FEAT_SME_FA64
- FEAT_SME_I16I64
- FEAT_SME_LUTv2
- FEAT_SME2
- FEAT_SME2p1
- FEAT_SSVE_FP8DOT2
- FEAT_SSVE_FP8DOT4
- FEAT_SSVE_FP8FMA
FEAT_FPMR is added in the first commit and then removed in a separate one to highlight it being removed from upstream LLVM 19. The intention is for it to be detectable at runtime through stdarch but not have a corresponding Rust compile-time feature.
A partial stabilization that only affects:
- AllocType<T>::new_uninit
- AllocType<T>::assume_init
- AllocType<[T]>::new_uninit_slice
- AllocType<[T]>::assume_init
where "AllocType" is Box, Rc, or Arc
exit: explain our expectations for the exit handlers registered in a Rust program
This documents the position of ``@Amanieu`` and others in https://github.com/rust-lang/rust/issues/126600: a library with an atexit handler that destroys state that other threads could still be working on is buggy. We do not consider it acceptable for a library to say "you must call the following cleanup function before exiting from `main` or calling `exit`". I don't know if this is established ``@rust-lang/libs-api`` consensus so I presume this will have to go through FCP.
Given that Rust supports concurrency, I don't think there is any way to write a sound Rust wrapper around a library that has such a required cleanup function: even if we made `exit` unsafe, and the Rust wrapper used the scope-with-callback approach to ensure it can run cleanup code before returning from the wrapper (like `thread::scope`), one could still call this wrapper in a second thread and then return from `main` while the wrapper runs. Making this sound would require `std` to provide a way to "block" returning from `main`, so that while the wrapper runs returning from `main` waits until the wrapper is done... that just doesn't seem feasible.
The `exit` docs do not seem like the best place to document this, but I also couldn't think of a better one.
Add SME aarch64 features already supported by LLVM and Linux.
This commit adds compiler support for the following features:
- FEAT_SME
- FEAT_SME_F16F16
- FEAT_SME_F64F64
- FEAT_SME_F8F16
- FEAT_SME_F8F32
- FEAT_SME_FA64
- FEAT_SME_I16I64
- FEAT_SME_LUTv2
- FEAT_SME2
- FEAT_SME2p1
- FEAT_SSVE_FP8DOT2
- FEAT_SSVE_FP8DOT4
- FEAT_SSVE_FP8FMA
