Make `_Unwind_Action` a type alias, not enum
It's bitflags in practice, so an enum is unsound, as an enum must only have the described values. The x86_64 psABI declares it as a `typedef int _Unwind_Action`, which seems reasonable. I made a newtype first but that was more annoying than just a typedef. We don't really use this value for much other than a short check.
I ran `x check library --target aarch64-unknown-linux-gnu,x86_64-pc-windows-gnu,x86_64-fortanix-unknown-sgx,x86_64-unknown-haiku,x86_64-unknown-fuchsi
a,x86_64-unknown-freebsd,x86_64-unknown-dragonfly,x86_64-unknown-netbsd,x86_64-unknown-openbsd,x86_64-unknown-redox,riscv64-linux-android,armv7-unknown-freebsd` (and some more but they failed to build for other reasons :D)
fixes#138558
r? workingjubilee have fun
It's bitflags in practice, so an enum is unsound, as an enum must only
have the described values. The x86_64 psABI declares it as a `typedef
int _Unwind_Action`, which seems reasonable. I made a newtype first but
that was more annoying than just a typedef. We don't really use this
value for much other than a short check.
Update the standard library to Rust 2024
This updates the standard library to Rust 2024. This includes the following notable changes:
- Macros are updated to use new expression fragment specifiers. This PR includes a test to illustrate the changes, primarily allowing `const {...}` expressions now.
- Some tests show a change in MIR drop order. We do not believe this will be an observable change ([see zulip discussion](500972873)).
Fixes https://github.com/rust-lang/rust/issues/133081
Use `std::mem::{size_of, size_of_val, align_of, align_of_val}` from the
prelude instead of importing or qualifying them.
These functions were added to all preludes in Rust 1.80.
Add support for wasm exception handling to Emscripten target
This is a draft because we need some additional setting for the Emscripten target to select between the old exception handling and the new exception handling. I don't know how to add a setting like that, would appreciate advice from Rust folks. We could maybe choose to use the new exception handling if `Ctarget-feature=+exception-handling` is passed? I tried this but I get errors from llvm so I'm not doing it right.
With #80608 the `unwinding` crate no longer builds. The upstream crate
has been updated to build by manually adding directives to the naked_asm
stream.
Bump the dependency in Rust to get this newer version. This fixes the
build for Xous, and closes#134403.
Signed-off-by: Sean Cross <sean@xobs.io>
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
The recent changes to naked `asm!()` macros made this unbuildable
on Xous. The upstream package maintainer released 0.2.3 to fix support
on newer nightly toolchains.
Update the dependency to 0.2.3, which is the oldest version that works
with the current nightly compiler.
This closes#131602 and fixes the build on xous.
Signed-off-by: Sean Cross <sean@xobs.io>
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.
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".
The code is written in a way to support 32-bit iOS and tvOS ARM devices,
for future compatibility even though we currently only have a target for
32-bit iOS ARM.
Add aarch64-apple-visionos and aarch64-apple-visionos-sim tier 3 targets
Introduces `aarch64-apple-visionos` and `aarch64-apple-visionos-sim` as tier 3 targets. This allows native development for the Apple Vision Pro's visionOS platform.
This work has been tracked in https://github.com/rust-lang/compiler-team/issues/642. There is a corresponding `libc` change https://github.com/rust-lang/libc/pull/3568 that is not required for merge.
Ideally we would be able to incorporate [this change](https://github.com/gimli-rs/object/pull/626) to the `object` crate, but the author has stated that a release will not be cut for quite a while. Therefore, the two locations that would reference the xrOS constant from `object` are hardcoded to their MachO values of 11 and 12, accompanied by TODOs to mark the code as needing change. I am open to suggestions on what to do here to get this checked in.
# Tier 3 Target Policy
At this tier, the Rust project provides no official support for a target, so we place minimal requirements on the introduction of targets.
> 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.)
See [src/doc/rustc/src/platform-support/apple-visionos.md](e88379034a/src/doc/rustc/src/platform-support/apple-visionos.md)
> 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.
This naming scheme matches `$ARCH-$VENDOR-$OS-$ABI` which is matches the iOS Apple Silicon simulator (`aarch64-apple-ios-sim`) and other Apple targets.
> 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 besubject 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.
This contribution is fully available under the standard Rust license with no additional legal restrictions whatsoever. This PR does not introduce any new dependency less permissive than the Rust license policy.
The new targets do not depend on proprietary libraries.
> 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.
This new target mirrors the standard library for watchOS and iOS, with minor divergences.
> 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.
Documentation is provided in [src/doc/rustc/src/platform-support/apple-visionos.md](e88379034a/src/doc/rustc/src/platform-support/apple-visionos.md)
> 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.
> * This requirement does not prevent part or all of this policy from being cited in an explicit contract or work agreement (e.g. to implement or maintain support for a target). This requirement exists to ensure that a developer or team responsible for reviewing and approving a target does not face any legal threats or obligations that would prevent them from freely exercising their judgment in such approval, even if such judgment involves subjective matters or goes beyond the letter of these requirements.
> 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.
> * 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.
> 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 acknowledge these requirements and intend to ensure that they are met.
This target does not touch any existing tier 2 or tier 1 targets and should not break any other targets.
This target is a Tier 3 target so it's not tested on CI, and it's broken
since last used so this commit fixes a small unwind-related issue that
cropped up in the meantime.
std support for wasm32 panic=unwind
Tracking issue: #118168
This adds std support for `-Cpanic=unwind` on wasm, and with it slightly more fleshed out rustc support. Now, the stable default is still panic=abort without exception-handling, but if you `-Zbuild-std` with `RUSTFLAGS=-Cpanic=unwind`, you get wasm exception-handling try/catch blocks in the binary:
```rust
#[no_mangle]
pub fn foo_bar(x: bool) -> *mut u8 {
let s = Box::<str>::from("hello");
maybe_panic(x);
Box::into_raw(s).cast()
}
#[inline(never)]
#[no_mangle]
fn maybe_panic(x: bool) {
if x {
panic!("AAAAA");
}
}
```
```wat
;; snip...
(try $label$5
(do
(call $maybe_panic
(local.get $0)
)
(br $label$1)
)
(catch_all
(global.set $__stack_pointer
(local.get $1)
)
(call $__rust_dealloc
(local.get $2)
(i32.const 5)
(i32.const 1)
)
(rethrow $label$5)
)
)
;; snip...
```
Stabilize `cfg_target_abi`
This stabilizes the `cfg` option called `target_abi`:
```rust
#[cfg(target_abi = "eabihf")]
```
Tracking issue: #80970fixes#78791resolves#80970
The `unwinding` crate supports processing unwinding data, and is written
entirely in Rust. This allows it to be ported to new platforms more
easily than using the llvm-based `libunwind`.
While `libunwind` is very well supported on major targets, it is
difficult to use on other targets. SGX is an example of this where Rust
carries custom patches in order to enable backtrace support.
This adds an alternative for supported architectures. Rather than
providing a custom target, `unwinding` allows for a solution that is
completely written in Rust.
This adds `xous` as the first consumer, and forthcoming patches will
modify libstd to take advantage of this.
Signed-off-by: Sean Cross <sean@xobs.io>
Linking libgcc is no longer supported (see #103673), so remove the
related link attributes and the check in unwind's build.rs. The check
was the last remaining significant piece of logic in build.rs, so
remove build.rs as well.
