Since android ndk version `r23-beta3`, `libgcc` has been replaced with
`libunwind`. This moves the linking of `libgcc`/`libunwind` into the
`unwind` crate where we check if the system compiler can find
`libunwind` and fall back to `libgcc` if needed.
- Split `sys_common::RWLock` between `StaticRWLock` and `MovableRWLock`
- Unbox `RwLock` on some platforms (Windows, Wasm and unsupported)
- Simplify `RwLock::into_inner`
To make way for a new IoSlice(Mut)::advance function that advances a
single slice.
Also changes the signature to accept a `&mut &mut [IoSlice]`, not
returning anything. This will better match the future IoSlice::advance
function.
Add #[track_caller] to panic_any
Report the panic location from the user code.
```rust
use std::panic;
use std::panic::panic_any;
fn main() {
panic::set_hook(Box::new(|panic_info| {
if let Some(location) = panic_info.location() {
println!(
"panic occurred in file '{}' at line {}",
location.file(),
location.line(),
);
} else {
println!("panic occurred but can't get location information...");
}
}));
panic_any(42);
}
````
Before:
`panic occurred in file '/rustc/ff2c947c00f867b9f012e28ba88cecfbe556f904/library/std/src/panic.rs' at line 59`
After:
`panic occurred in file 'src/main.rs' at line 17`
In particular the `is_dir`, `is_file` and `exists` functions says that querying a file requires querying the directory. On Windows this is not normally true.
Add inline attr to CString::into_inner so it can optimize out NonNull checks
It seems that currently if you convert any of the standard library's container to a pointer and then to a NonNull pointer, all will optimize out the NULL check except `CString`(https://godbolt.org/z/YPKW9G5xn),
because for some reason `CString::into_inner` isn't inlined even though it's a private function that should compile into a simple `mov` instruction.
Adding a simple `#[inline]` attribute solves this, code example:
```rust
use std::ffi::CString;
use std::ptr::NonNull;
pub fn cstring_nonull(mut n: CString) -> NonNull<i8> {
NonNull::new(CString::into_raw(n)).unwrap()
}
```
assembly before:
```asm
__ZN3wat14cstring_nonull17h371c755bcad76294E:
.cfi_startproc
pushq %rbp
.cfi_def_cfa_offset 16
.cfi_offset %rbp, -16
movq %rsp, %rbp
.cfi_def_cfa_register %rbp
callq __ZN3std3ffi5c_str7CString10into_inner17h28ece07b276e2878E
testq %rax, %rax
je LBB0_2
popq %rbp
retq
LBB0_2:
leaq l___unnamed_1(%rip), %rdi
leaq l___unnamed_2(%rip), %rdx
movl $43, %esi
callq __ZN4core9panicking5panic17h92a83fa9085a8f73E
.cfi_endproc
.section __TEXT,__const
l___unnamed_1:
.ascii "called `Option::unwrap()` on a `None` value"
l___unnamed_3:
.ascii "wat.rs"
.section __DATA,__const
.p2align 3
l___unnamed_2:
.quad l___unnamed_3
.asciz "\006\000\000\000\000\000\000\000\006\000\000\000(\000\000"
```
Assembly after:
```asm
__ZN3wat14cstring_nonull17h9645eb9341fb25d7E:
.cfi_startproc
pushq %rbp
.cfi_def_cfa_offset 16
.cfi_offset %rbp, -16
movq %rsp, %rbp
.cfi_def_cfa_register %rbp
movq %rdi, %rax
popq %rbp
retq
.cfi_endproc
```
(Related discussion on zulip: https://rust-lang.zulipchat.com/#narrow/stream/219381-t-libs/topic/NonNull.20From.3CBox.3CT.3E.3E)
doc: clarify Mutex::try_lock, etc. errors
Clarify error returns from Mutex::try_lock, RwLock::try_read,
RwLock::try_write to make it more obvious that both poisoning
and the lock being already locked are possible errors.
Bump bootstrap compiler to beta 1.53.0
This PR bumps the bootstrap compiler to version 1.53.0 beta, as part of our usual release process (this was supposed to be Wednesday's step, but creating the beta release took longer than expected).
The PR also includes the "Bootstrap: skip rustdoc fingerprint for building docs" commit, see the reasoning [on Zulip](https://zulip-archive.rust-lang.org/241545trelease/88450153betabootstrap.html).
r? `@Mark-Simulacrum`
Fix `vxworks`
Some PRs made the `vxworks` target not build anymore. This PR fixes that:
- #82973: copy `ExitStatusError` implementation from `unix`.
- #84716: no `libc::chroot` available on `vxworks`, so for now don't implement `os::unix::fs::chroot`.
add an example to explain std::io::Read::read returning 0 in some cases
I have always found the explanation about `Read::read` returning 0 to indicate EOF but not indefinitely, so here's more info using Linux as example. I can also add example code if necessary
MSVC: Avoid using jmp stubs for dll function imports
Windows import libraries contain two symbols for every function: `__imp_FunctionName` and `FunctionName` (where `FunctionName` is the name of the function to be imported).
`__imp_FunctionName` contains the address of the imported function. This will be filled in by the Windows executable loader at runtime. `FunctionName` contains a jmp stub that simply jumps to the address given by `__imp_FunctionName`. E.g. it's a function that solely contains a single jmp instruction:
```asm
jmp __imp_FunctionName
```
When using an external DLL function in Rust, by default the linker will link to FunctionName, causing a bit of indirection at runtime. In Microsoft's C++ it's possible to instead tell it to insert calls to the address in `__imp_FunctionName` by using the `__declspec(dllimport)` attribute. In Rust it's possible to get effectively the same behaviour using the `#[link]` attribute on `extern` blocks.
----
The second commit also merges multiple `extern` blocks into one block. This is because otherwise Rust will currently create duplicate linker arguments for each block. In this case having duplicates shouldn't matter much other than the noise when displaying the linker command.
Windows implementation of feature `path_try_exists`
Draft of a Windows implementation of `try_exists` (#83186).
The first commit reorganizes the code so I would be interested to get some feedback on if this is a good idea or not. It moves the `Path::try_exists` function to `fs::exists`. leaving the former as a wrapper for the latter. This makes it easier to provide platform specific implementations and matches the `fs::metadata` function.
The other commit implements a Windows specific variant of `exists`. I'm still figuring out my approach so this is very much a first draft. Eventually this will need some more eyes from knowledgable Windows people.
Clarify error returns from Mutex::try_lock, RwLock::try_read,
RwLock::try_write to make it more obvious that both poisoning
and the lock being already locked are possible errors.
std: Don't inline TLS accessor on MinGW
This is causing [issues] on Cargo's own CI for MinGW and given the
original investigation there's no reason that MinGW should work when
MSVC doesn't, this this tweaks the MSVC exception to being a Windows exception.
[issues]: 2626676503 (step):9:2453
This is causing [issues] on Cargo's own CI for MinGW and given the
original investigation there's no reason that MinGW should work when
MSVC doesn't, this this tweaks the MSVC exception to being a Windows exception.
[issues]: 2626676503 (step):9:2453
Move `std::memchr` to `sys_common`
`std::memchr` is a thin abstraction over the different `memchr` implementations in `sys`, along with documentation and tests. The module is only used internally by `std`, nothing is exported externally. Code like this is exactly what the `sys_common` module is for, so this PR moves it there.
Update list of allowed aarch64 features
I recently added these features to std_detect for aarch64 linux, pending [review](https://github.com/rust-lang/stdarch/pull/1146).
I have commented any features not supported by LLVM 9, the current minimum version for Rust. Some (PAuth at least) were renamed between 9 & 12 and I've left them disabled. TME, however, is not in LLVM 9 but I've left it enabled.
See https://github.com/rust-lang/stdarch/issues/993
Rollup of 8 pull requests
Successful merges:
- #84717 (impl FromStr for proc_macro::Literal)
- #85169 (Add method-toggle to <details> for methods)
- #85287 (Expose `Concurrent` (private type in public i'face))
- #85315 (adding time complexity for partition_in_place iter method)
- #85439 (Add diagnostic item to `CStr`)
- #85464 (Fix UB in documented example for `ptr::swap`)
- #85470 (Fix invalid CSS rules for a:hover)
- #85472 (CTFE Machine: do not expose Allocation)
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
Introduce `sys_common::rt::rtprintpanic!` to replace `sys_common::util` functionality
This PR introduces a new macro `rtprintpanic!`, similar to `sys_common::util::dumb_print` and uses that macro to replace all `sys_common::util` functionality.
