don't splice from files into pipes in io::copy
This fixes potential data ordering issue where a write performed after a copy operation could become visible in the copy even though it signaled completion.
I assumed that by not setting `SPLICE_F_MOVE` we would be safe and the kernel would do a copy in kernel space and we could avoid the read-write syscall and copy-to/from-userspace costs. But apparently that flag only makes a difference when splicing from a pipe, but not when splicing into it.
Context: https://lkml.org/lkml/2023/2/9/673
sync::mpsc: synchronize receiver disconnect with initialization
Receiver disconnection relies on the incorrect assumption that `head.index != tail.index` implies that the channel is initialized (i.e `head.block` and `tail.block` point to allocated blocks). However, it can happen that `head.index != tail.index` and `head.block == null` at the same time which leads to a segfault when a channel is dropped in that state.
This can happen because initialization is performed in two steps. First, the tail block is allocated and the `tail.block` is set. If that is successful `head.block` is set to the same pointer. Importantly, initialization is skipped if `tail.block` is not null.
Therefore we can have the following situation:
1. Thread A starts to send the first value of the channel, observes that `tail.block` is null and begins initialization. It sets `tail.block` to point to a newly allocated block and then gets preempted. `head.block` is still null at this point.
2. Thread B starts to send the second value of the channel, observes that `tail.block` *is not* null and proceeds with writing its value in the allocated tail block and sets `tail.index` to 1.
3. Thread B drops the receiver of the channel which observes that `head.index != tail.index` (0 and 1 respectively), therefore there must be messages to drop. It starts traversing the linked list from `head.block` which is still a null pointer, leading to a segfault.
This PR fixes this problem by waiting for initialization to complete when `head.index != tail.index` and the `head.block` is still null. A similar check exists in `start_recv` for similar reasons.
Fixes#110001
Custom MIR: Support `BinOp::Offset`
Since offset doesn't have an infix operator, a new function `Offset` is added which is lowered to `Rvalue::BinaryOp(BinOp::Offset, ..)`
r? ```@oli-obk``` or ```@tmiasko``` or ```@JakobDegen```
Initial support for loongarch64-unknown-linux-gnu
Hi, We hope to add a new port in rust for LoongArch.
LoongArch intro
LoongArch is a RISC style ISA which is independently designed by Loongson
Technology in China. It is divided into two versions, the 32-bit version (LA32)
and the 64-bit version (LA64). LA64 applications have application-level
backward binary compatibility with LA32 applications. LoongArch is composed of
a basic part (Loongson Base) and an expanded part. The expansion part includes
Loongson Binary Translation (LBT), Loongson VirtualiZation (LVZ), Loongson SIMD
EXtension (LSX) and Loongson Advanced SIMD EXtension(LASX).
Currently the LA464 processor core supports LoongArch ISA and the Loongson
3A5000 processor integrates 4 64-bit LA464 cores. LA464 is a four-issue 64-bit
high-performance processor core. It can be used as a single core for high-end
embedded and desktop applications, or as a basic processor core to form an
on-chip multi-core system for server and high-performance machine applications.
Documentations:
ISA:
https://loongson.github.io/LoongArch-Documentation/LoongArch-Vol1-EN.html
ABI:
https://loongson.github.io/LoongArch-Documentation/LoongArch-ELF-ABI-EN.html
More docs can be found at:
https://loongson.github.io/LoongArch-Documentation/README-EN.html
Since last year, we have locally adapted two versions of rust, rust1.41 and rust1.57, and completed the test locally.
I'm not sure if I'm submitting all the patches at once, so I split up the patches and here's one of the commits
Improve the floating point parser in dec2flt.
Greetings everyone,
I've benn studying the rust floating point parser recently and made the following tweaks:
* Remove all remaining traces of `unsafe`. The parser is now 100% safe Rust.
* The trick in which eight digits are processed in parallel is now in a loop.
* Parsing of inf/NaN values has been reworked.
On my system, the changes result in performance improvements for some input values.
resolve: Preserve reexport chains in `ModChild`ren
This may be potentially useful for
- avoiding uses of `hir::ItemKind::Use` (which usually lead to correctness issues)
- preserving documentation comments on all reexports, including those from other crates
- preserving and checking stability/deprecation info on reexports
- all kinds of diagnostics
The second commit then migrates some hacky logic from rustdoc to `module_reexports` to make it simpler and more correct.
Ideally rustdoc should use `module_reexports` immediately at the top level, so `hir::ItemKind::Use`s are never used.
The second commit also fixes issues with https://github.com/rust-lang/rust/pull/109330 and therefore
Fixes https://github.com/rust-lang/rust/issues/109631
Fixes https://github.com/rust-lang/rust/issues/109614
Fixes https://github.com/rust-lang/rust/issues/109424
Receiver disconnection relies on the incorrect assumption that
`head.index != tail.index` implies that the channel is initialized (i.e
`head.block` and `tail.block` point to allocated blocks). However, it
can happen that `head.index != tail.index` and `head.block == null` at
the same time which leads to a segfault when a channel is dropped in
that state.
This can happen because initialization is performed in two steps. First,
the tail block is allocated and the `tail.block` is set. If that is
successful `head.block` is set to the same pointer. Importantly,
initialization is skipped if `tail.block` is not null.
Therefore we can have the following situation:
1. Thread A starts to send the first value of the channel, observes that
`tail.block` is null and begins initialization. It sets `tail.block`
to point to a newly allocated block and then gets preempted.
`head.block` is still null at this point.
2. Thread B starts to send the second value of the channel, observes
that `tail.block` *is not* null and proceeds with writing its value
in the allocated tail block and sets `tail.index` to 1.
3. Thread B drops the receiver of the channel which observes that
`head.index != tail.index` (0 and 1 respectively), therefore there
must be messages to drop. It starts traversing the linked list from
`head.block` which is still a null pointer, leading to a segfault.
This PR fixes this problem by waiting for initialization to complete
when `head.index != tail.index` and the `head.block` is still null. A
similar check exists in `start_recv` for similar reasons.
Fixes#110001
Signed-off-by: Petros Angelatos <petrosagg@gmail.com>
To avoid link time dependency between core and compiler-builtins, when
using opt-level that implicitly enables -Zshare-generics.
While compiler-builtins should be compiled with -Zshare-generics
disabled, the -Zbuild-std does not ensure this at the moment.
Fix buffer overrun in bootstrap and (test-only) symlink_junction
I don't think these can be hit in practice, due to their inputs being valid paths. It's also not security-sensitive code, but just... bad vibes.
I think this is still not really the right way to do this (in terms of path correctness), but is no worse than it was.
r? `@ChrisDenton`
Original `var_os` description said that it _may_ return an error if the value contains `=` or NUL. Let's make no promises on the `None` return value in these situation either, keep it in the [potential mood](https://en.wikipedia.org/wiki/Grammatical_mood#Potential).
Update compiler-builtins to 0.1.91 to bring in msp430 shift primitive…
… fixes.
This fixes unsoundness on MSP430 where `compiler-builtins` and LLVM didn't agree on the width of the shift amount argument of the shifting primitives (4 bytes vs 2 bytes). See https://github.com/rust-lang/compiler-builtins/pull/522 for more details.
binary_heap: Optimize Extend implementation.
This PR makes the `Extend` implementation for `BinaryHeap` no longer rely on specialization, so that it always use the bulk rebuild optimization that was previously only available for the `Vec` specialization.
Improve grammar of Iterator.partition_in_place
This is my first PR against Rust, please let me know if there's anything I should be providing here! I didn't find any instructions specific to documentation grammar in the [std-dev guide](https://std-dev-guide.rust-lang.org/documentation/summary.html).
Optimize `LazyCell` size
`LazyCell` can only store either the initializing function or the data it produces, so it does not need to reserve the space for both. Similar to #107329, but uses an `enum` instead of a `union`.
Move `doc(primitive)` future incompat warning to `invalid_doc_attributes`
Fixes#88070.
It's been a while since this was turned into a "future incompatible lint" so I think we can now turn it into a hard error without problem.
r? `@jyn514`
Insert alignment checks for pointer dereferences when debug assertions are enabled
Closes https://github.com/rust-lang/rust/issues/54915
- [x] Jake tells me this sounds like a place to use `MirPatch`, but I can't figure out how to insert a new basic block with a new terminator in the middle of an existing basic block, using `MirPatch`. (if nobody else backs up this point I'm checking this as "not actually a good idea" because the code looks pretty clean to me after rearranging it a bit)
- [x] Using `CastKind::PointerExposeAddress` is definitely wrong, we don't want to expose. Calling a function to get the pointer address seems quite excessive. ~I'll see if I can add a new `CastKind`.~ `CastKind::Transmute` to the rescue!
- [x] Implement a more helpful panic message like slice bounds checking.
r? `@oli-obk`
Refactor glibc time64 support, riscv32 always has 64-bit `time_t`
Refactor existing support for 64-bit `time_t` on 32-bit glibc platforms, as riscv32 `time_t` is 64-bit by default. Split out of #109773.
Improve documentation for str::replace() and str::replacen()
Currently, to know what the function will return when the pattern doesn't match, the docs require the reader to understand the implementation detail and mentally evaluate or run the example code. It is not immediately clear.
This PR makes it more explicit so the reader can quickly find the information.
Rollup of 7 pull requests
Successful merges:
- #106985 (Enhanced doucmentation of binary search methods for `slice` and `VecDeque` for unsorted instances)
- #109509 (compiletest: Don't allow tests with overlapping prefix names)
- #109719 (RELEASES: Add "Only support Android NDK 25 or newer" to 1.68.0)
- #109748 (Don't ICE on `DiscriminantKind` projection in new solver)
- #109749 (Canonicalize float var as float in new solver)
- #109761 (Drop binutils on powerpc-unknown-freebsd)
- #109766 (Fix title for openharmony.md)
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
Enhanced doucmentation of binary search methods for `slice` and `VecDeque` for unsorted instances
Fixes#106746. Issue #106746 raises the concern that the binary search methods for slices and deques aren't explicit enough about the fact that they are only applicable to sorted slices/deques. I changed the explanation for these methods. I took the relatively harsh description of the behaviour of binary search on unsorted collections ("unspecified and meaningless") from the description of the [`partition_point`](https://doc.rust-lang.org/std/primitive.slice.html#method.partition_point) method:
> If this slice is not partitioned, the returned result is unspecified and meaningless, as this method performs a kind of binary search.
Partial stabilization of `once_cell`
This PR aims to stabilize a portion of the `once_cell` feature:
- `core::cell::OnceCell`
- `std::cell::OnceCell` (re-export of the above)
- `std::sync::OnceLock`
This will leave `LazyCell` and `LazyLock` unstabilized, which have been moved to the `lazy_cell` feature flag.
Tracking issue: https://github.com/rust-lang/rust/issues/74465 (does not fully close, but it may make sense to move to a new issue)
Future steps for separate PRs:
- ~~Add `#[inline]` to many methods~~ #105651
- Update cranelift usage of the `once_cell` crate
- Update rust-analyzer usage of the `once_cell` crate
- Update error messages discussing once_cell
## To be stabilized API summary
```rust
// core::cell (in core/cell/once.rs)
pub struct OnceCell<T> { .. }
impl<T> OnceCell<T> {
pub const fn new() -> OnceCell<T>;
pub fn get(&self) -> Option<&T>;
pub fn get_mut(&mut self) -> Option<&mut T>;
pub fn set(&self, value: T) -> Result<(), T>;
pub fn get_or_init<F>(&self, f: F) -> &T where F: FnOnce() -> T;
pub fn into_inner(self) -> Option<T>;
pub fn take(&mut self) -> Option<T>;
}
impl<T: Clone> Clone for OnceCell<T>;
impl<T: Debug> Debug for OnceCell<T>
impl<T> Default for OnceCell<T>;
impl<T> From<T> for OnceCell<T>;
impl<T: PartialEq> PartialEq for OnceCell<T>;
impl<T: Eq> Eq for OnceCell<T>;
```
```rust
// std::sync (in std/sync/once_lock.rs)
impl<T> OnceLock<T> {
pub const fn new() -> OnceLock<T>;
pub fn get(&self) -> Option<&T>;
pub fn get_mut(&mut self) -> Option<&mut T>;
pub fn set(&self, value: T) -> Result<(), T>;
pub fn get_or_init<F>(&self, f: F) -> &T where F: FnOnce() -> T;
pub fn into_inner(self) -> Option<T>;
pub fn take(&mut self) -> Option<T>;
}
impl<T: Clone> Clone for OnceLock<T>;
impl<T: Debug> Debug for OnceLock<T>;
impl<T> Default for OnceLock<T>;
impl<#[may_dangle] T> Drop for OnceLock<T>;
impl<T> From<T> for OnceLock<T>;
impl<T: PartialEq> PartialEq for OnceLock<T>
impl<T: Eq> Eq for OnceLock<T>;
impl<T: RefUnwindSafe + UnwindSafe> RefUnwindSafe for OnceLock<T>;
unsafe impl<T: Send> Send for OnceLock<T>;
unsafe impl<T: Sync + Send> Sync for OnceLock<T>;
impl<T: UnwindSafe> UnwindSafe for OnceLock<T>;
```
No longer planned as part of this PR, and moved to the `rust_cell_try` feature gate:
```rust
impl<T> OnceCell<T> {
pub fn get_or_try_init<F, E>(&self, f: F) -> Result<&T, E> where F: FnOnce() -> Result<T, E>;
}
impl<T> OnceLock<T> {
pub fn get_or_try_init<F, E>(&self, f: F) -> Result<&T, E> where F: FnOnce() -> Result<T, E>;
}
```
I am new to this process so would appreciate mentorship wherever needed.
Use `getentropy()` instead of `/dev/urandom` on Emscripten
`/dev/urandom` is usually available on Emscripten, except when using
the special `NODERAWFS` filesystem backend, which replaces all normal
filesystem access with direct Node.js operations.
Since this filesystem backend directly access the filesystem on the
OS, it is not recommended to depend on `/dev/urandom`, especially
when trying to run the Wasm binary on OSes that are not Unix-based.
This can be considered a non-functional change, since Emscripten
implements `/dev/urandom` in the same way as `getentropy()` when not
linking with `-sNODERAWFS`.
Remove ~const from alloc
There is currently an effort underway to stop using `~const Trait`, temporarily, so as to refactor the logic underlying const traits with relative ease. This means it has to go from the standard library, as well.
I have taken the initial step of just removing these impls from alloc, as removing them from core is a much more tangled task. In addition, all of these implementations are one more-or-less logically-connected group, so reverting their deconstification as a group seems like it will also be sensible.
r? `@fee1-dead`
Use random `HashMap` keys on Hermit
Initializing the keys with random data provided by the libOS avoids HashDOS attacks and similar issues.
CC `@stlankes`
Support TLS access into dylibs on Windows
This allows access to `#[thread_local]` in upstream dylibs on Windows by introducing a MIR shim to return the address of the thread local. Accesses that go into an upstream dylib will call the MIR shim to get the address of it.
`convert_tls_rvalues` is introduced in `rustc_codegen_ssa` which rewrites MIR TLS accesses to dummy calls which are replaced with calls to the MIR shims when the dummy calls are lowered to backend calls.
A new `dll_tls_export` target option enables this behavior with a `false` value which is set for Windows platforms.
This fixes https://github.com/rust-lang/rust/issues/84933.
Rollup of 8 pull requests
Successful merges:
- #91793 (socket ancillary data implementation for FreeBSD (from 13 and above).)
- #92284 (Change advance(_back)_by to return the remainder instead of the number of processed elements)
- #102472 (stop special-casing `'static` in evaluation)
- #108480 (Use Rayon's TLV directly)
- #109321 (Erase impl regions when checking for impossible to eagerly monomorphize items)
- #109470 (Correctly substitute GAT's type used in `normalize_param_env` in `check_type_bounds`)
- #109562 (Update ar_archive_writer to 0.1.3)
- #109629 (remove obsolete `givens` from regionck)
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
Add a builtin `FnPtr` trait that is implemented for all function pointers
r? `@ghost`
Rebased version of https://github.com/rust-lang/rust/pull/99531 (plus adjustments mentioned in the PR).
If perf is happy with this version, I would like to land it, even if the diagnostics fix in 9df8e1befb5031a5bf9d8dfe25170620642d3c59 only works for `FnPtr` specifically, and does not generally improve blanket impls.
Change advance(_back)_by to return the remainder instead of the number of processed elements
When advance_by can't advance the iterator by the number of requested elements it now returns the amount by which it couldn't be advanced instead of the amount by which it did.
This simplifies adapters like chain, flatten or cycle because the remainder doesn't have to be calculated as the difference between requested steps and completed steps anymore.
Additionally switching from `Result<(), usize>` to `Result<(), NonZeroUsize>` reduces the size of the result and makes converting from/to a usize representing the number of remaining steps cheap.
Add `#[inline]` to CStr trait implementations
Fixes#109674
I noticed other usages of traits on `CStr` weren't being inlined, so also added hints to the other implementations
A successful advance is now signalled by returning `0` and other values now represent the remaining number
of steps that couldn't be advanced as opposed to the amount of steps that have been advanced during a partial advance_by.
This simplifies adapters a bit, replacing some `match`/`if` with arithmetic. Whether this is beneficial overall depends
on whether `advance_by` is mostly used as a building-block for other iterator methods and adapters or whether
we also see uses by users where `Result` might be more useful.
Stabilize `nonnull_slice_from_raw_parts`
FCP is done: https://github.com/rust-lang/rust/issues/71941#issuecomment-1100910416
Note that this doesn't const-stabilize `NonNull::slice_from_raw_parts` as `slice_from_raw_parts_mut` isn't const-stabilized yet. Given #67456 and #57349, it's not likely available soon, meanwhile, stabilizing only the feature makes some sense, I think.
Closes#71941
Add #[inline] to as_deref
While working on https://github.com/rust-lang/rust/pull/109247 I found an `as_deref` call in the compiler that should have been inlined. This fixes the missing inlining (but doesn't address the perf issues I was chasing).
r? `@thomcc`
Clarify that copied allocators must behave the same
Currently, the safety documentation for `Allocator` says that a cloned or moved allocator must behave the same as the original. However, it does not specify that a copied allocator must behave the same, and it's possible to construct an allocator that permits being moved or cloned, but sometimes produces a new allocator when copied.
<details>
<summary>Contrived example which results in a Miri error</summary>
```rust
#![feature(allocator_api, once_cell, strict_provenance)]
use std::{
alloc::{AllocError, Allocator, Global, Layout},
collections::HashMap,
hint,
marker::PhantomPinned,
num::NonZeroUsize,
pin::Pin,
ptr::{addr_of, NonNull},
sync::{LazyLock, Mutex},
};
mod source_allocator {
use super::*;
// `SourceAllocator` has 3 states:
// - invalid value: is_cloned == false, source != self.addr()
// - source value: is_cloned == false, source == self.addr()
// - cloned value: is_cloned == true
pub struct SourceAllocator {
is_cloned: bool,
source: usize,
_pin: PhantomPinned,
}
impl SourceAllocator {
// Returns a pinned source value (pointing to itself).
pub fn new_source() -> Pin<Box<Self>> {
let mut b = Box::new(Self {
is_cloned: false,
source: 0,
_pin: PhantomPinned,
});
b.source = b.addr();
Box::into_pin(b)
}
fn addr(&self) -> usize {
addr_of!(*self).addr()
}
// Invalid values point to source 0.
// Source values point to themselves.
// Cloned values point to their corresponding source.
fn source(&self) -> usize {
if self.is_cloned || self.addr() == self.source {
self.source
} else {
0
}
}
}
// Copying an invalid value produces an invalid value.
// Copying a source value produces an invalid value.
// Copying a cloned value produces a cloned value with the same source.
impl Copy for SourceAllocator {}
// Cloning an invalid value produces an invalid value.
// Cloning a source value produces a cloned value with that source.
// Cloning a cloned value produces a cloned value with the same source.
impl Clone for SourceAllocator {
fn clone(&self) -> Self {
if self.is_cloned || self.addr() != self.source {
*self
} else {
Self {
is_cloned: true,
source: self.source,
_pin: PhantomPinned,
}
}
}
}
static SOURCE_MAP: LazyLock<Mutex<HashMap<NonZeroUsize, usize>>> =
LazyLock::new(Default::default);
// SAFETY: Wraps `Global`'s methods with additional tracking.
// All invalid values share blocks with each other.
// Each source value shares blocks with all cloned values pointing to it.
// Cloning an allocator always produces a compatible allocator:
// - Cloning an invalid value produces another invalid value.
// - Cloning a source value produces a cloned value pointing to it.
// - Cloning a cloned value produces another cloned value with the same source.
// Moving an allocator always produces a compatible allocator:
// - Invalid values remain invalid when moved.
// - Source values cannot be moved, since they are always pinned to the heap.
// - Cloned values keep the same source when moved.
unsafe impl Allocator for SourceAllocator {
fn allocate(&self, layout: Layout) -> Result<NonNull<[u8]>, AllocError> {
let mut map = SOURCE_MAP.lock().unwrap();
let block = Global.allocate(layout)?;
let block_addr = block.cast::<u8>().addr();
map.insert(block_addr, self.source());
Ok(block)
}
unsafe fn deallocate(&self, block: NonNull<u8>, layout: Layout) {
let mut map = SOURCE_MAP.lock().unwrap();
let block_addr = block.addr();
// SAFETY: `block` came from an allocator that shares blocks with this allocator.
if map.remove(&block_addr) != Some(self.source()) {
hint::unreachable_unchecked()
}
Global.deallocate(block, layout)
}
}
}
use source_allocator::SourceAllocator;
// SAFETY: `alloc1` and `alloc2` must share blocks.
unsafe fn test_same(alloc1: &SourceAllocator, alloc2: &SourceAllocator) {
let ptr = alloc1.allocate(Layout:🆕:<i32>()).unwrap();
alloc2.deallocate(ptr.cast(), Layout:🆕:<i32>());
}
fn main() {
let orig = &*SourceAllocator::new_source();
let orig_cloned1 = &orig.clone();
let orig_cloned2 = &orig.clone();
let copied = &{ *orig };
let copied_cloned1 = &copied.clone();
let copied_cloned2 = &copied.clone();
unsafe {
test_same(orig, orig_cloned1);
test_same(orig_cloned1, orig_cloned2);
test_same(copied, copied_cloned1);
test_same(copied_cloned1, copied_cloned2);
test_same(orig, copied); // error
}
}
```
</details>
This could result in issues in the future for algorithms that specialize on `Copy` types. Right now, nothing in the standard library that depends on `Allocator + Clone` is susceptible to this issue, but I still think it would make sense to specify that copying an allocator is always as valid as cloning it.
Currently, to know what the function will return when the pattern
doesn't match, the docs require the reader to understand the
implementation detail and mentally evaluate or run the example
code. It is not immediately clear.
This PR makes it more explicit so the reader can quickly find the
information.
Implement Default for some alloc/core iterators
Add `Default` impls to the following collection iterators:
* slice::{Iter, IterMut}
* binary_heap::IntoIter
* btree::map::{Iter, IterMut, Keys, Values, Range, IntoIter, IntoKeys, IntoValues}
* btree::set::{Iter, IntoIter, Range}
* linked_list::IntoIter
* vec::IntoIter
and these adapters:
* adapters::{Chain, Cloned, Copied, Rev, Enumerate, Flatten, Fuse, Rev}
For iterators which are generic over allocators it only implements it for the global allocator because we can't conjure an allocator from nothing or would have to turn the allocator field into an `Option` just for this change.
These changes will be insta-stable.
ACP: https://github.com/rust-lang/libs-team/issues/77
Add #[inline] to the Into for From impl
I was skimming through the standard library MIR and I noticed a handful of very suspicious `Into::into` calls in `alloc`. ~Since this is a trivial wrapper function, `#[inline(always)]` seems appropriate.;~ `#[inline]` works too and is a lot less spooky.
r? `@thomcc`
Shrink unicode case-mapping LUTs by 24k
I was looking into the binary bloat of a small program using `str::to_lowercase` and `str::to_uppercase`, and noticed that the lookup tables used for case mapping had a lot of zero-bytes in them. The reason for this is that since some characters map to up to three other characters when lower or uppercased, the LUTs store a `[char; 3]` for each character. However, the vast majority of cases only map to a single new character, in other words most of the entries are e.g. `(lowerc, [upperc, '\0', '\0'])`.
This PR introduces a new encoding scheme for these tables.
The changes reduces the size of my test binary by about 24K.
I've also done some `#[bench]`marks on unicode-heavy test data, and found that the performance of both `str::to_lowercase` and `str::to_uppercase` improves by up to 20%. These measurements are obviously very dependent on the character distribution of the data.
Someone else will have to decide whether this more complex scheme is worth it or not, I was just goofing around a bit and here's what came out of it 🤷♂️ No hard feelings if this isn't wanted!
fix typo in the creation of OpenOption for RustyHermit
Due to this typo we have to build a workaround for issue hermitcore/libhermit-rs#191.
RustyHermit is a tier 3 platform and backward compatibility does not have to be guaranteed.
Add block-based mutex unlocking example
This modifies the existing example in the Mutex docs to show both `drop()` and block based early unlocking.
Alternative to #81872, which is getting closed.
panic_immediate_abort requires abort as a panic strategy
Guide `panic_immediate_abort` users away from `-Cpanic=unwind` and towards `-Cpanic=abort` to avoid an accidental use of the feature with the unwind strategy, e.g., on a targets where unwind is the default.
The `-Cpanic=unwind` combination doesn't offer the same benefits, since the code would still be generated under the assumption that functions implemented in Rust can unwind.
Clarify `Error::last_os_error` can be weird
Fundamentally, querying the OS for error codes is a process that is deeply subject to the whims of chance and fortune. We can account for OS, but not for every combination of platform APIs. A compiled binary may not recognize new errors introduced years later. We should clarify a few especially odd situations, and what they mean: We can effectively promise nothing... if you ask for Rust to decode errors where none have occurred.
This allows removing mention of ErrorKind::Uncategorized.
That error variant is hidden deliberately, so we should not explicitly mention it.
This fixes#106937.
Since you had an opinion also: Does this solution seem acceptable?
r? ``@ChrisDenton``
Rollup of 7 pull requests
Successful merges:
- #108541 (Suppress `opaque_hidden_inferred_bound` for nested RPITs)
- #109137 (resolve: Querify most cstore access methods (subset 2))
- #109380 (add `known-bug` test for unsoundness issue)
- #109462 (Make alias-eq have a relation direction (and rename it to alias-relate))
- #109475 (Simpler checked shifts in MIR building)
- #109504 (Stabilize `arc_into_inner` and `rc_into_inner`.)
- #109506 (make param bound vars visibly bound vars with -Zverbose)
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
Stabilize `arc_into_inner` and `rc_into_inner`.
Stabilize the `arc_into_inner` and `rc_into_inner` library features and thus close#106894.
The changes in this PR also resolve the FIXMEs for adjusting the documentation upon stabilization, and I’ve additionally included some very minor documentation improvements.
```@rustbot``` label +T-libs-api -T-libs
Updates `interpret`, `codegen_ssa`, and `codegen_cranelift` to consume the new cast instead of the intrinsic.
Includes `CastTransmute` for custom MIR building, to be able to test the extra UB.
Custom MIR: Allow optional RET type annotation
This currently doesn't compile because the type of `RET` is inferred, which fails if RET is a composite type and fields are initialised separately.
```rust
#![feature(custom_mir, core_intrinsics)]
extern crate core;
use core::intrinsics::mir::*;
#[custom_mir(dialect = "runtime", phase = "optimized")]
fn fn0() -> (i32, bool) {
mir! ({
RET.0 = 0;
RET.1 = true;
Return()
})
}
```
```
error[E0282]: type annotations needed
--> src/lib.rs:8:9
|
8 | RET.0 = 0;
| ^^^ cannot infer type
For more information about this error, try `rustc --explain E0282`.
```
This PR allows the user to manually specify the return type with `type RET = ...;` if required:
```rust
#[custom_mir(dialect = "runtime", phase = "optimized")]
fn fn0() -> (i32, bool) {
mir! (
type RET = (i32, bool);
{
RET.0 = 0;
RET.1 = true;
Return()
}
)
}
```
The syntax is not optimal, I'm happy to see other suggestions. Ideally I wanted it to be a normal type annotation like `let RET: ...;`, but this runs into the multiple parsing options error during macro expansion, as it can be parsed as a normal `let` declaration as well.
r? ```@oli-obk``` or ```@tmiasko``` or ```@JakobDegen```
move Option::as_slice to intrinsic
````@scottmcm```` suggested on #109095 I use a direct approach of unpacking the operation in MIR lowering, so here's the implementation.
cc ````@nikic```` as this should hopefully unblock #107224 (though perhaps other changes to the prior implementation, which I left for bootstrapping, are needed).
Drop all messages in bounded channel when destroying the last receiver
Fixes#107466 by splitting the `disconnect` function for receivers/transmitters and dropping all messages in `disconnect_receivers` like the unbounded channel does. Since all receivers must be dropped before the channel is, the messages will already be discarded at that point, so the `Drop` implementation for the channel can be removed.
``@rustbot`` label +T-libs +A-concurrency
Windows: make `Command` prefer non-verbatim paths
When spawning Commands, the path we use can end up being queried using `env::current_exe` (or the equivalent in other languages). Not all applications handle these paths properly therefore we should have a stronger preference for non-verbatim paths when spawning processes.
Implement read_buf for a few more types
Implement read_buf for TcpStream, Stdin, StdinLock, ChildStdout,
ChildStderr (and internally for AnonPipe, Handle, Socket), so
that it skips buffer initialization.
The other provided methods like read_to_string and read_to_end are
implemented in terms of read_buf and so benefit from the optimization
as well.
This commit also implements read_vectored and is_read_vectored where
applicable.
Document `Iterator::sum/product` for Option/Result
Closes#105266
We already document the similar behavior for `collect()` so I believe it makes sense to add this too. The Option/Result implementations *are* documented on their respective pages and the page for `Sum`, but buried amongst many other trait impls which doesn't make it very discoverable.
`````@rustbot````` label +A-docs
Remove the assume(!is_null) from Vec::as_ptr
At a guess, this code is leftover from LLVM was worse at keeping track of the niche information here. In any case, we don't need this anymore: Removing this `assume` doesn't get rid of the `nonnull` attribute on the return type.
Add inlining annotations in `dec2flt`.
Currently, the combination of `dec2flt` being generic and the `FromStr` implementaions
containing inline anttributes causes massive amounts of assembly to be generated whenever
these implementation are used. In addition, the assembly has calls to function which ought to
be inlined, but they are not (even when using lto).
This Pr fixes this.
Distribute libntdll.a with windows-gnu toolchains
This allows the OS loader to load essential functions (e.g. read/write file) at load time instead of lazily doing so at runtime.
r? libs
Improve `Iterator::collect_into` documentation
This improves the examples in the documentation of `Iterator::collect_into`, replacing the usages of `println!` with `assert_eq!` as suggested on [IRLO](https://internals.rust-lang.org/t/18534/9).
Due to this typo we have to build a workaround for issue
hermitcore/libhermit-rs#191.
RustyHermit is a tier 3 platform and backward compatibility does
not have to be guaranteed.
read_buf_exact: on error, all read bytes are appended to the buffer
Guarantee that when `read_buf_exact` returns, all bytes read will be
appended to the buffer. Including the case when the operations fails.
The motivating use case are operations on a non-blocking reader. When
`read_buf_exact` fails with `ErrorKind::WouldBlock` error, the operation
can be resumed at a later time.
Beautify pin! docs
This makes pin docs a little bit less jargon-y and easier to read, by
* splitting up the sentences
* making them less interrupted by punctuation
* turning the footnotes into paragraphs, as they contain useful information that shouldn't be hidden in footnotes. Footnotes also interrupt the read flow.
Use `size_of_val` instead of manual calculation
Very minor thing that I happened to notice in passing, but it's both shorter and [means it gets `mul nsw`](https://rust.godbolt.org/z/Y9KxYETv5), so why not.
