std: Add Motor OS std library port
Motor OS was added as a no-std Tier-3 target in
[PR 146848](https://github.com/rust-lang/rust/pull/146848) as x86_64-unknown-motor.
This PR adds the std library for Motor OS.
While the PR may seem large, all it does is proxy
std pal calls to [moto-rt](https://crates.io/crates/moto-rt). Where there is some non-trivial
code (e.g. thread::spawn), it is quite similar, often
identical, to what other platforms do.
Motor OS was added as a no-std Tier-3 target in
https://github.com/rust-lang/rust/pull/146848
as x86_64-unknown-motor.
This patch/PR adds the std library for Motor OS.
While the patch may seem large, all it does is proxy
std pal calls to moto-rt. When there is some non-trivial
code (e.g. thread::spawn), it is quite similar, and often
identical, to what other platforms do.
This commit adds a new tier 3 target to rustc, `wasm32-wasip3`. This
follows in the footsteps of the previous `wasm32-wasip2` target and is
used to represent binding to the WASIp3 set of APIs managed by the WASI
subgroup to the WebAssembly Community Group.
As of now the WASIp3 set of APIs are not finalized nor standardized.
They're in the process of doing so and the current trajectory is to have
the APIs published in December of this year. The goal here is to get the
wheels turning in Rust to have the target in a
more-ready-than-nonexistent state by the time this happens in December.
For now the `wasm32-wasip3` target looks exactly the same as
`wasm32-wasip2` except that `target_env = "p3"` is specified. This
indicates to crates in the ecosystem that WASIp3 APIs should be used,
such as the [`wasip3` crate]. Over time this target will evolve as
implementation in guest toolchains progress, notably:
* The standard library will use WASIp3 APIs natively once they're
finalized in the WASI subgroup.
* Support through `wasi-libc` will be updated to use WASIp3 natively
which Rust will then transitively use.
* Longer-term, features such as cooperative multithreading will be added
to the WASIp3-track of targets to enable using `std::thread`, for
example, on this target.
These changes are all expected to be non-breaking changes for users of
this target. Runtimes supporting WASIp3, currently Wasmtime and Jco,
support WASIp2 APIs as well and will work with components whether or not
they import WASIp2, both WASIp2 and WASIp3, or just WASIp3 APIs. This
means that changing the internal implementation details of libstd over
time is expected to be a non-breaking change.
[`wasip3` crate]: https://crates.io/crates/wasip3
Add `std` support for `armv7a-vex-v5`
This PR adds standard library support for the VEX V5 Brain (`armv7a-vex-v5` target). It is more-or-less an updated version of the library-side work done in rust-lang/rust#131530.
This was a joint effort between me, `@lewisfm,` `@max-niederman,` `@Gavin-Niederman` and several other members of the [`vexide` project](https://github.com/vexide/).
## Background
VEXos is a fairly unconventional operating system, with user code running in a restricted enviornment with regards to I/O capabilities and whatnot. As such, several OS-dependent APIs are unsupported or have partial support (such as `std::net`, `std::process`, and most of `std::thread`). A more comprehensive list of what does or doesn't work is outlined in the [updated target documentation](https://github.com/vexide/rust/blob/vex-std/src/doc/rustc/src/platform-support/armv7a-vex-v5.md). Despite these limitations, we believe that `libstd` support on this target still has value to users, especially given the popular use of this hardware for educational purposes. For some previous discussion on this matter, see [this comment](https://github.com/rust-lang/rust/pull/131530#issuecomment-2432856841).
## SDK Linkage
VEXos doesn't really ship with an official `libc` or POSIX-style platform API (and though it does port newlib, these are stubbed on top of the underlying SDK). Instead, VEX provides their own SDK for calling platform APIs. Their official SDK is kept proprietary (with public headers), though open-source implementations exist. Following the precedent of the `armv6k-nintendo-3ds` team's work in rust-lang/rust#95897, we've opted not to directly link `libstd` to any SDK with the expectation that users will provide their own with one of the following options:
- [`vex-sdk-download`](https://github.com/vexide/vex-sdk/tree/main/packages/vex-sdk-download), which downloads an official proprietary SDK from VEX using a build script.
- [`vex-sdk-jumptable`](https://crates.io/crates/vex-sdk-jumptable), which is a compatible, open-source reimplementation of the SDK using firmware jumps.
- [`vex-sdk-pros`](https://github.com/vexide/vex-sdk/tree/main/packages/vex-sdk-pros), which uses the [PROS kernel](https://github.com/purduesigbots/pros) as a provider for SDK functions.
- Linking their own implementation or stubbing the functions required by libstd.
The `vex-sdk` crate used in the VEXos PAL provides `libc`-style FFI bindings for any compatible system library, so any of these options *should* work fine. A functional demo project using `vex-sdk-download` can be found [here](https://github.com/vexide/armv7a-vex-v5-demo/tree/main).
## Future Work
This PR implements virtually everything we are currently able to implement given the current capabilities of the platform. The exception to this is file directory enumeration, though the implementation of that is sufficiently [gross enough](https://github.com/vexide/vexide/blob/c6c5bad11e035cf4e51d429dca7e427210185ed4/packages/vexide-core/src/fs/mod.rs#L987) to drive us away from supporting this officially.
Additionally, I have a working branch implementing the `panic_unwind` runtime for this target, which is something that would be nice to see in the future, though given the volume of compiler changes i've deemed it out-of-scope for this PR.
The recent work on the WASIp2 target being integrated into the standard
library ended up causing a bug in nightly on the target. This has now
been fixed in the `wasi` crate so this commit pulls in the updated
version to ensure bindings work correctly.
This commit is the start of an effort to support WASIp2 natively in the
standard library. Before this commit the `wasm32-wasip2` target behaved
exactly like `wasm32-wasip1` target by importing APIs from the core wasm
module `wasi_snapshot_preview1`. These APIs are satisfied by the
`wasm-component-ld` target by using an [adapter] which implements WASIp1
in terms of WASIp2. This adapter comes at a cost, however, in terms of
runtime indirection and instantiation cost, so ideally the adapter would
be removed entirely. The purpose of this adapter was to provide a
smoother on-ramp from WASIp1 to WASIp2 when it was originally created.
The `wasm32-wasip2` target has been around for long enough now that it's
much more established. Additionally the only thing historically blocking
using WASIp2 directly was implementation effort. Work is now underway to
migrate wasi-libc itself to using WASIp2 directly and now seems as good
a time as any to migrate the Rust standard library too.
Implementation-wise the milestones here are:
* The `wasm32-wasip2` target now also depends on the `wasi` crate at
version 0.14.* in addition to the preexisting dependency of 0.11.*.
The 0.14.* release series binds WASIp2 APIs instead of WASIp1 APIs.
* Some preexisting naming around `mod wasi` or `wasi.rs` was renamed to
`wasip1` where appropriate. For example `std::sys::pal::wasi` is now
called `std::sys::pal::wasip1`.
* More platform-specific WASI modules are now split between WASIp1 and
WASIp2. For example getting the current time, randomness, and
process arguments now use WASIp2 APIs directly instead of using WASIp1
APIs that require an adapter.
It's worth pointing out that this PR does not migrate the entire
standard library away from using WASIp1 APIs on the `wasm32-wasip2`
target. Everything related to file descriptors and filesystem APIs is
still using WASIp1. Migrating that is left for a future PR. In the
meantime the goal of this change is to lay the groundwork necessary for
migrating in the future. Eventually the goal is to drop the `wasi`
0.11.* dependency on the `wasm32-wasip2` target (the `wasm32-wasip1`
target will continue to retain this dependency).
[adapter]: https://github.com/bytecodealliance/wasmtime/blob/main/crates/wasi-preview1-component-adapter/README.md
Migrate the standard library from using the external `cfg_if` crate to
using the now-built-in `cfg_select` macro.
This does not yet eliminate the dependency from
`library/std/Cargo.toml`, because while the standard library itself no
longer uses `cfg_if`, it also incorporates the `backtrace` crate, which
does.
Migration assisted by the following vim command (after selecting the
full `cfg_if!` invocation):
```
'<,'>s/\(cfg_if::\)\?cfg_if/cfg_select/ | '<,'>s/^\( *\)} else {/\1}\r\1_ => {/c | '<,'>s/^\( *\)} else if #\[cfg(\(.*\))\] /\1}\r\1\2 => /e | '<,'>s/if #\[cfg(\(.*\))\] {/\1 => {/e
```
This is imperfect, but substantially accelerated the process. This
prompts for confirmation on the `} else {` since that can also appear
inside one of the arms. This also requires manual intervention to handle
any multi-line conditions.
`compiler-builtins` is already in the crate graph via `alloc`, and all
features related to `compiler-builtins` goes through `alloc`. There
isn't any reason that `std` needs this direct dependency, so remove it.
Remove `compiler-builtins-{no-asm,mangled-names}`
Remove `compiler-builtins-no-asm`
This feature used to be for when Cranelift didn't support inline
assembly, but its last uses were removed in 52933e0bd2 ("Don't disable
inline asm usage in compiler-builtins when the cranelift backend is
enabled"). and cba05a7a14 ("Support naked functions").
This doesn't remove the feature from the `compiler-builtins` crate, that
will be done separately in the subtree repo.
---
Remove `compiler-builtins-mangled-names`
This config was added in 207de019dc ("libary: Forward
compiler-builtins "asm" and "mangled-names" feature") but it does not
appear this has ever been used. The PR adding it (rust-lang/rust#78472) says that
this was exposed to help with configuration and points at the [Hermit
Cargo config], but as far as I can tell, this feature name has never
been mentioned in that repository's git history.
Thus, clean up a seemingly unneeded feature.
[Hermit Cargo config]: https://github.com/hermit-os/hermit-rs/blob/ab2b830930e6a9a98c8294997a8183feeabeda4a/.cargo/config
Upgrade the `fortanix-sgx-abi` dependency
0.6.1 removes the `compiler-builtins` dependency, part of RUST-142265. The breaking change from 0.5 to 0.6 is for an update to the `insecure_time` API [1].
I validated that `./x c library --target x86_64-fortanix-unknown-sgx` completes successfully with this change.
Link: https://github.com/fortanix/rust-sgx/commit/a34e9767f37d6585c18bdbd31cddcadc56670d57 [1]
This config was added in 207de019dc ("libary: Forward
compiler-builtins "asm" and "mangled-names" feature") but it does not
appear this has ever been used. The PR adding it (RUST-78472) says that
this was exposed to help with configuration and points at the [Hermit
Cargo config], but as far as I can tell, this feature name has never
been mentioned in that repository's git history.
Thus, clean up a seemingly unneeded feature.
[Hermit Cargo config]: https://github.com/hermit-os/hermit-rs/blob/ab2b830930e6a9a98c8294997a8183feeabeda4a/.cargo/config
This feature used to be for when Cranelift didn't support inline
assembly, but its last uses were removed in 52933e0bd2 ("Don't disable
inline asm usage in compiler-builtins when the cranelift backend is
enabled"). and cba05a7a14 ("Support naked functions").
This doesn't remove the feature from the `compiler-builtins` crate, that
will be done separately in the subtree repo.
This primarily pulls in alexcrichton/dlmalloc-rs/55 and
alexcrichton/dlmalloc-rs/54 to address 144199. Notably the highest byte
in the wasm address space is no longer allocatable and additionally the
allocator internally uses `wrapping_add` instead of `add` on pointers
since on 32-bit platforms offsets might be larger than half the address
space.
Linting public reexport of private dependencies
Part of public/private dependencies rust-lang/rust#44663
Partially addresses rust-lang/rust#71043
I'm adding a warning for reexports of private dependencies into `rustc_resolve`. I get that this should not be a warning, but should instead be a lint to be controlled by the feature gate, but I did not figure out how exactly to do that at that point. I tried doing the same thing as is done in `rustc_privacy`, but the linting system is not ready yet as far as I understand the error I got, so I made a warning for now instead. Some guidance on how to emit lints with `dcx` would be appreciated.
This also sets the `std_detect` crate as a public dependency of `std` because some macros are reexported from there. I did not check closer, but the other option may be to allow the specific reexports instead.
0.6.1 removes the `compiler-builtins` dependency, part of RUST-142265.
The breaking change from 0.5 to 0.6 is for an update to the
`insecure_time` API [1].
I validated that `./x c library --target x86_64-fortanix-unknown-sgx`
completes successfully with this change.
Link: https://github.com/fortanix/rust-sgx/commit/a34e9767f37d6585c18bdbd31cddcadc56670d57 [1]
0.37.0 is a semver-breaking release but the only breakage is in
`elf::R_RISCV_GNU_*` and `pe::IMAGE_WEAK_EXTERN_*` constants, as well as
Mach-O dyld. This API is not used by `std`, so we should be fine to
upgrade.
This new version also includes functionality for parsing Wasm object
files that we may eventually like to make use of.
Also includes the minor bump from 0.37.0 to 0.37.1 to help [1].
Changelog: https://github.com/gimli-rs/object/blob/master/CHANGELOG.md#0370
[1]: https://github.com/rust-lang/rust/issues/142265
Many of `std`'s dependency have a dependency on the crates.io
`compiler-builtins` when used with the feature
`rustc-std-workspace-core`. Use a Cargo patch to select the in-tree
version instead.
`compiler-builtins` is also added as a dependency of
`rustc-std-workspace-core` so these crates can remove their crates.io
dependency in the future.
Implement the internal feature `cfg_target_has_reliable_f16_f128`
Support for `f16` and `f128` is varied across targets, backends, and backend versions. Eventually we would like to reach a point where all backends support these approximately equally, but until then we have to work around some of these nuances of support being observable.
Introduce the `cfg_target_has_reliable_f16_f128` internal feature, which provides the following new configuration gates:
* `cfg(target_has_reliable_f16)`
* `cfg(target_has_reliable_f16_math)`
* `cfg(target_has_reliable_f128)`
* `cfg(target_has_reliable_f128_math)`
`reliable_f16` and `reliable_f128` indicate that basic arithmetic for the type works correctly. The `_math` versions indicate that anything relying on `libm` works correctly, since sometimes this hits a separate class of codegen bugs.
These options match configuration set by the build script at [1]. The logic for LLVM support is duplicated as-is from the same script. There are a few possible updates that will come as a follow up.
The config introduced here is not planned to ever become stable, it is only intended to replace the build scripts for `std` tests and `compiler-builtins` that don't have any way to configure based on the codegen backend.
MCP: https://github.com/rust-lang/compiler-team/issues/866
Closes: https://github.com/rust-lang/compiler-team/issues/866
[1]: https://github.com/rust-lang/rust/blob/555e1d0386f024a8359645c3217f4b3eae9be042/library/std/build.rs#L84-L186
---
The second commit makes use of this config to replace `cfg_{f16,f128}{,_math}` in `library/`. I omitted providing a `cfg(bootstrap)` configuration to keep things simpler since the next beta branch is in two weeks.
try-job: aarch64-gnu
try-job: i686-msvc-1
try-job: test-various
try-job: x86_64-gnu
try-job: x86_64-msvc-ext2
New compiler configuration has been introduced that is designed to
replace the build script configuration `reliable_f16`, `reliable_f128`,
`reliable_f16_math`, and `reliable_f128_math`. Do this replacement here,
which allows us to clean up `std`'s build script.
All tests are gated by `#[cfg(bootstrap)]` rather than doing a more
complicated `cfg(bootstrap)` / `cfg(not(bootstrap))` split since the
next beta split is within two weeks.
bump libc to 0.2.171 to fix xous
Due to a reorganization in the `libc` crate, the `xous` target broke with version `0.2.170`. Bump libc to `0.2.171` to fix nightly.
Matthias Krüger