std: stop backtracing when the frames are full
This is a defensive measure to mitigate the infinite unwind loop seen in #53372. That case will still repeatedly unwind `__rust_try`, but now it will at least stop when `cx.frames` is full.
r? @alexcrichton
Use #[non_exhaustive] on internal enums
This replaces `__Nonexhaustive` variants (and variants thereof) with `#[non_exhaustive]`. These were mostly unstable previously, with the exception of the `cloudabi` enums and `Level` in proc_macro: these were `#[doc(hidden)]`, so clearly intended not to be used directly. It should be safe to replace all of these.
std: Use target_pointer_width for BACKTRACE_ELF_SIZE
The former code used `target.contains("64")` to detect Elf64 targets,
but this is inaccurate in a few cases:
- `s390x-unknown-linux-gnu` is 64-bit
- `sparcv9-sun-solaris` is 64-bit
- `x86_64-unknown-linux-gnux32` is 32-bit
Instead the `std` build script can use `CARGO_CFG_TARGET_POINTER_WIDTH`
to reliably detect 64-bit targets for libbacktrace.
Also update to backtrace-sys 0.1.24 for alexcrichton/backtrace-rs#122.
This commit adds the necessary definitions for target specs and such as well as
the necessary support in libstd to compile basic `aarch64-pc-windows-msvc`
binaries. The target is not currently built on CI, but it can be built locally
with:
./configure --target=aarch64-pc-windows-msvc --set rust.lld
./x.py build src/libstd --target aarch64-pc-windows-msvc
Currently this fails to build `libtest` due to a linker bug (seemingly in LLD?)
which hasn't been investigate yet. Otherwise though with libstd you can build a
hello world program (linked with LLD). I've not tried to execute it yet, but it
at least links!
Full support for this target is still a long road ahead, but this is hopefully a
good stepping stone to get started.
Points of note about this target are:
* Currently defaults to `panic=abort` as support is still landing in LLVM for
SEH on AArch64.
* Currently defaults to LLD as a linker as I was able to get farther with it
than I was with `link.exe`
The former code used `target.contains("64")` to detect Elf64 targets,
but this is inaccurate in a few cases:
- `s390x-unknown-linux-gnu` is 64-bit
- `sparcv9-sun-solaris` is 64-bit
- `x86_64-unknown-linux-gnux32` is 32-bit
Instead the `std` build script can use `CARGO_CFG_TARGET_POINTER_WIDTH`
to reliably detect 64-bit targets for libbacktrace.
Also update to backtrace-sys 0.1.24 for alexcrichton/backtrace-rs#122.
Idiomatic improvements to IP method
Since match ergonomics and slice patterns are stable this might be more idiomatic modern Rust implementations of these methods? Or well, slice patterns with `..` are not stabilized yet, so maybe we want to specify all fields but with `_`?
Don't panic on std::env::vars() when env is null.
Fixes#53200.
Reviewer(s):
* Do I need to do any `#[cfg()]` here?
* Is this use of libc ok for a dev-dependency?
Add links to std::char::REPLACEMENT_CHARACTER from docs.
There are a few places where we mention the replacement character in the
docs, and it could be helpful for users to utilize the constant which is
available in the standard library, so let’s link to it!
Show that Command can be reused and remodified
The prior documentation did not make it clear this was possible.
I wanted to make the `list_dir` example work on Windows, but I don't know if passing "/" will error or show the root of the current volume (e.g. `C:`).
r? @GuillaumeGomez
There are a few places where we mention the replacement character in the
docs, and it could be helpful for users to utilize the constant which is
available in the standard library, so let’s link to it!
Rollup of 15 pull requests
Successful merges:
- #52773 (Avoid unnecessary pattern matching against Option and Result)
- #53082 (Fix doc link (again))
- #53094 (Automatically expand section if url id point to one of its component)
- #53106 (atomic ordering docs)
- #53110 (Account for --remap-path-prefix in save-analysis)
- #53116 (NetBSD: fix signedess of char)
- #53179 (Whitelist wasm32 simd128 target feature)
- #53183 (Suggest comma when missing in macro call)
- #53207 (Add individual docs for rotate_{left, right})
- #53211 ([nll] enable feature(nll) on various crates for bootstrap)
- #53214 ([nll] enable feature(nll) on various crates for bootstrap: part 2)
- #53215 (Slightly refactor syntax_ext/format)
- #53217 (inline some short functions)
- #53219 ([nll] enable feature(nll) on various crates for bootstrap: part 3)
- #53222 (A few cleanups for rustc_target)
clarify partially initialized Mutex issues
Using a `sys_common::mutex::Mutex` without calling `init` is dangerous, and yet there are some places that do this. I tried to find all of them and add an appropriate comment about reentrancy.
I found two places where (I think) reentrancy can actually occur, and was not able to come up with an argument for why this is okay. Someone who knows `io::lazy` and/or `sys_common::at_exit_imp` should have a careful look at this.
