implement `Box::take`
Tracking issue: https://github.com/rust-lang/rust/issues/147212
I'm not entirely sure about the wording of the doc comment, if anyone has any suggestions that'd be great :)
Support `#[rustc_align_static]` inside `thread_local!`
Tracking issue: rust-lang/rust#146177
```rust
thread_local! {
#[rustc_align_static(64)]
static SO_ALIGNED: u64 = const { 0 };
}
```
This increases the amount of recursion the macro performs (once per attribute in addition to the previous once per item), making it easier to hit the recursion limit. I’ve added workarounds to limit the impact in the case of long doc comments, but this still needs a crater run just in case.
r? libs
``@rustbot`` label A-attributes A-macros A-thread-locals F-static_align T-libs
Rollup of 8 pull requests
Successful merges:
- rust-lang/rust#146593 (Allow specifying multiple bounds for same associated item, except in trait objects)
- rust-lang/rust#147177 ([DebugInfo] Fix MSVC tuple child creation)
- rust-lang/rust#147195 (iter repeat: add tests for new count and last behavior)
- rust-lang/rust#147202 (Swap order of `resolve_coroutine_interiors` and `handle_opaque_type_uses`)
- rust-lang/rust#147204 (Refactor ArrayWindows to use a slice)
- rust-lang/rust#147219 (Add proper error handling for closure in impl)
- rust-lang/rust#147226 (include `outer_inclusive_binder` of pattern types)
- rust-lang/rust#147230 (Fix typo in 'unfulfilled_lint_expectation' to plural)
r? `@ghost`
`@rustbot` modify labels: rollup
Rollup of 6 pull requests
Successful merges:
- rust-lang/rust#143069 (Add fast-path for accessing the current thread id)
- rust-lang/rust#146518 (Improve the documentation around `ZERO_AR_DATE`)
- rust-lang/rust#146596 (Add a dummy codegen backend)
- rust-lang/rust#146617 (Don’t suggest foreign `doc(hidden)` types in "the following other types implement trait" diagnostics)
- rust-lang/rust#146635 (cg_llvm: Stop using `as_c_char_ptr` for coverage-related bindings)
- rust-lang/rust#147184 (Fix the bevy implied bounds hack for the next solver)
r? `@ghost`
`@rustbot` modify labels: rollup
Accessing the thread id is often used in profiling and debugging, as
well as some approaches for sound single-threaded access to data.
Currently the only way to access the thread id is by first obtaining a
handle to the current thread. While this is not exactly slow, it does
require an atomic inc-ref and dec-ref operation, as well as the
injection of `Thread`'s drop code into the caller.
This publicly exposes the existing fast-path for accessing the current
thread id.
Add repr(align(2)) to RcInner and ArcInner
`Rc` currently assumes that `RcInner` has at least 2-byte alignment, but on AVR, `usize` has 1-byte alignment (this is because the AVR has 1-byte register sizes, so having 2-byte alignment is generally useless), breaking this assumption.
9f32ccf35f/library/alloc/src/rc.rs (L3005-L3008)
This PR adds `repr(align(2))` to force `RcInner` to always have at least 2-byte alignment.
Note that `ArcInner` doesn't need `repr(align(2))` because atomic types have the alignment same as its size. This PR adds a comment about this.
Add `Path::has_trailing_sep` and related methods
Implements rust-lang/libs-team#335.
Tracking issue: rust-lang/rust#142503
Notable differences from ACP:
* `trim_trailing_sep` was added to `Path` since it felt reasonable to ensure that the inverse operation was available.
* Per suggestion of `@kennytm,` added `push_trailing_sep` and `pop_trailing_sep` to `PathBuf` in addition to `set_trailing_sep`.
This also updates some of the docs on various `Path` methods to use the term "trailing separator" instead of "trailing slash" for consistency.
std: implement `hostname`
Resolves https://github.com/rust-lang/libs-team/issues/330
Tracking issue: https://github.com/rust-lang/rust/issues/135142
This is based on rust-lang/rust#135141, but I've reimplemented the UNIX version, which now:
* uses `sysconf(_SC_HOST_NAME_MAX)` as an initial buffer length
* returns `OutOfMemory` if the `Vec` allocation fails
* retries the operation if it detects that the name returned by `gethostname` was truncated
Additionally, as part of the rebase, I had to move some WinSock abstractions (initialisation and error access) to `sys::pal` so that they can be accessed from `sys::net::hostname`.
CC ``@orowith2os`` (and thank you for your work!)
Use `Iterator::eq` and (dogfood) `eq_by` in compiler and library
Now that rust-lang/rust#137122 has landed, we can replace stuff that looks like:
```rust
let a: &[T];
let b: &[T];
let eq = a.len() == b.len() && a.iter().zip(b).all(|(a,b)| a == b)
```
with the much simpler `a.iter().eq(b)`, without losing the perf benefit of the different-length-fast-path.
Also dogfooded `Iterator::eq_by` (cc rust-lang/rust#64295 ) while I'm at it.
First commit (4d1b6fad230f8a5ccceccc7562eadc4ea50059da) should be very straightforward to review, second one (049a4606cb3906787aedf508ee8eea09c2bb3b9a) is slightly more creative, but IMHO a nice cleanup.
Rollup of 7 pull requests
Successful merges:
- rust-lang/rust#133477 (Detect tuple structs that are unconstructable due to re-export)
- rust-lang/rust#146929 (compiletest: Remove old-output-capture and become a stage0 bootstrap tool)
- rust-lang/rust#146979 (constify Default on Nanoseconds)
- rust-lang/rust#147092 (Do not compute optimized MIR if code does not type-check.)
- rust-lang/rust#147112 (all 48 keywords in just 300 characters)
- rust-lang/rust#147122 (Fix some crash-test directives)
- rust-lang/rust#147127 (Add a leading dash to linker plugin arguments in the gcc codegen)
r? `@ghost`
`@rustbot` modify labels: rollup
Skip stack overflow handler for panic=immediate-abort
std installs guard pages and a signal handler to ensure that stackoverflows 1) terminate abruptly and 2) print an nice message. Even for panic=immediate-abort, 1) is desirable, we don't want silent data corruption there. But 2) is completely unnecessary, as users deliberately *don't* want nice messages, they want minimum binary size.
Therefore, skip the entire guard signal handler setup, which saves a lot of bytes.
I tested this with a hello world binary using fat LTO, build-std, panic=immediate-abort, opt-level=s, strip=debuginfo.
`size` reports significant savings:
```
text data bss dec hex filename
15252 1032 104 16388 4004 tiny-before
6881 964 48 7893 1ed5 tiny-after2
```
`nm -U` goes from 71 to 56, getting rid of a bunch of stack overflow related symbols. The disk size goes from `31k` to `24k`.
The impact on the error message is minimal, as the message was already
missing.
before:
```
fish: Job 1, './tiny-so-before' terminated by signal SIGABRT (Abort)
```
after:
```
fish: Job 1, './tiny-so-after' terminated by signal SIGSEGV (Address boundary error)
```
I didn't test the Windows part, but it likely also has savings.
redox: switch to colon as path separator
We recently changed this in order to better comply with assumptions about Unix-like systems. The current PATH is set to `/usr/bin` with no separators in order to ease the transition.
formatting_options: fix alternate docs 0b/0o mixup
The descriptions of the alternate forms of Octal and Binary were swapped in the doc comment for FormattingOptions::alternate().
Remove most `#[track_caller]` from allocating Vec methods
They cause significant binary size overhead while contributing little value.
closesrust-lang/rust#146963, see that issue for more details.
Introduce CoerceShared lang item and trait, and basic Reborrow tests
Part of rust-lang/rust#145612: This introduces the `CoerceShared` trait which is the `Reborrow` equivalent of a `&mut T` -> `&T` coercion. The trait has a `Target` GAT which makes this (currently) unique in the `core/src/marker.rs`; I'm not sure if this can be considered problematic. Maybe this is not the way such things should be done at the marker trait level? Or maybe it is fine.
Improtantly, this PR introduces a battery of basic `Reborrow` and `CoerceShared` tests. These test the very basics of the feature; custom marker types intended to have exclusive semantics (`Custom<'a>(PhantomData<&'a mut ()>)`), custom exclusive reference wrappers, and standard library exclusive reference wrappers (`Pin<&mut T>` and `Option<&mut T>`). None of these of course work since the implementation for `Reborrow` and `CoerceShared` is entirely missing, but this is the first step towards making these work.
Future PRs will introduce more tests, such as "recursive" reborrowing (ie. reborrowing structs that contain multiple reborrowable fields) and checks around the lifetime semantics of reborrowing ie. that a reborrow produces a new type with the same lifetime as the original.
std installs guard pages and a signal handler to ensure that stackoverflows 1) terminate abruptly and 2) print an nice message. Even for panic=immediate-abort, 1) is desirable, we don't want silent data corruption there. But 2) is completely unnecessary, as users deliberately *don't* want nice messages, they want minimum binary size.
Therefore, skip the entire guard signal handler setup, which saves a lot of bytes.
I tested this with a hello world binary using fat LTO, build-std, panic=immediate-abort, opt-level=s, strip=debuginfo.
`size` reports significant savings:
```
text data bss dec hex filename
15252 1032 104 16388 4004 tiny-before
6881 964 48 7893 1ed5 tiny-after2
```
`nm -U` goes from 71 to 56, getting rid of a bunch of stack overflow related symbols. The disk size goes from `31k` to `24k`.
The impact on the error message is minimal, as the message was already
missing.
before:
```
fish: Job 1, './tiny-so-before' terminated by signal SIGABRT (Abort)
```
after:
```
fish: Job 1, './tiny-so-after' terminated by signal SIGSEGV (Address boundary error)
```
