docs(rustc): Improve discoverable of Cargo docs
In preparing Cargo's blog post for 1.80, I tried to find the documentation for the lint configuration and I couldn't. The link is only visible from the lint itself, which isn't where I started, and the side bar, which was collapsed for me.
The first place I went was the docs for `unexpected_cfgs` because this is configuration for that lint. If using lint configuration were a one off, I could see skipping it here. However, when we discussed this with at least one T-compiler member, there was interest in using this for other lints in the future. To that end, it seems like we should be exposing this with the lint itself.
The second place I checked was the `check-cfg` documentation. This now has a call out for the sub-page.
Add `target_env = "p1"` to the `wasm32-wasip1` target
This commit sets the `target_env` key for the
`wasm32-wasi{,p1,p1-threads}` targets to the string `"p1"`. This mirrors how the `wasm32-wasip2` target has `target_env = "p2"`. The intention of this is to more easily detect each target in downstream crates to enable adding custom code per-target.
cc #125803
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Rollup of 9 pull requests
Successful merges:
- #126039 (Promote `arm64ec-pc-windows-msvc` to tier 2)
- #126075 (Remove `DebugWithInfcx` machinery)
- #126228 (Provide correct parent for nested anon const)
- #126232 (interpret: dyn trait metadata check: equate traits in a proper way)
- #126242 (Simplify provider api to improve llvm ir)
- #126294 (coverage: Replace the old span refiner with a single function)
- #126295 (No uninitalized report in a pre-returned match arm)
- #126312 (Update `rustc-perf` submodule)
- #126322 (Follow up to splitting core's PanicInfo and std's PanicInfo)
r? `@ghost`
`@rustbot` modify labels: rollup
Add no_std Xtensa targets support
Adds no_std Xtensa targets. This enables using Rust on ESP32, ESP32-S2 and ESP32-S3 chips.
Tier 3 policy:
> 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.)
`@MabezDev` and I (`@SergioGasquez)` will maintain the targets.
> 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.
The target triple is consistent with other targets.
> 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.
We follow the same naming convention as other 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 does not introduce any legal issues.
> The target must not introduce license incompatibilities.
There are no license incompatibilities
> Anything added to the Rust repository must be under the standard Rust license (MIT OR Apache-2.0).
Everything added is under that licenses
> 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 be subject to any new license requirements.
Requirements are not changed for any other target.
> 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.
The linker used by the targets is the GCC linker from the GCC toolchain cross-compiled for Xtensa. GNU GPL.
> "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.
No such terms exist for this target
> 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.
Understood
> 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.
The target already implements core.
> 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.
Here is how to build for the target https://docs.esp-rs.org/book/installation/riscv-and-xtensa.html and it also covers how to run binaries on the target.
> 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.
Understood
> 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.
No other targets should be affected
> Tier 3 targets must be able to produce assembly using at least one of rustc's supported backends from any host target.
It can produce assembly, but it requires a custom LLVM with Xtensa support (https://github.com/espressif/llvm-project/). The patches are trying to be upstreamed (https://github.com/espressif/llvm-project/issues/4)
Recommend to never display zero disambiguators when demangling v0 symbols
This PR extends the [v0 symbol mangling documentation](https://doc.rust-lang.org/rustc/symbol-mangling/v0.html) with the strong recommendation that demanglers should never display zero-disambiguators, especially when dealing with `crate-root`.
Being able to rely on `C3foo` to be rendered as `foo` (i.e. without explicit disambiguator value) rather than as `foo[0]` allows the compiler to encode things like new basic types in a backward compatible way. This idea has been originally proposed by `@eddyb` in [the discussion around supporting `f16` and `f128` in the v0 mangling scheme](https://github.com/rust-lang/rust/pull/122106). It is a generally useful mechanism for supporting a certain class of new elements in the v0 mangling scheme in a backward compatible way (whether as a temporary workaround until downstream tooling has picked up grammar changes or as a permanent encoding).
cc `@tgross35`
Clarify our tier 1 Windows Server support
I've been asked a number of times about our minimum Windows Server support so this PR updates the documentation to be more explicit.
Note that this doesn't change our support at all, it just clarifies it. Windows Server 2016 is the first "Windows 10" server OS (specifically it has the same [build number](https://en.wikipedia.org/wiki/Windows_Server_2016#Release_to_manufacturing) as Windows 10 1607).
Add a co-maintainer for the two ARMv4T targets
This adds a second maintainer to the `armv4t-none-eabi` and `thumbv4t-none-eabi` targets, a necessary step on the path to Tier 2
ARM Target Docs Update
Updates the ARM target docs, drawing more attention to the `arm-none-eabi` target group by placing all targets *within* that group as a sub-list in the Table of Contents.
Also updates the `armv4t-none-eabi` page (maintainer signoff: I'm that target's maintainer) to clarify that the page covers the arm version and the thumb version of the target, but that the target group page has the full info because there's nothing really specific to say for those targets.
Show files produced by `--emit foo` in json artifact notifications
Right now it is possible to ask `rustc` to save some intermediate representation into one or more files with `--emit=foo`, but figuring out what exactly was produced is difficult. This pull request adds information about `llvm_ir` and `asm` intermediate files into notifications produced by `--json=artifacts`.
Related discussion: https://internals.rust-lang.org/t/easier-access-to-files-generated-by-emit-foo/20477
Motivation - `cargo-show-asm` parses those intermediate files and presents them in a user friendly way, but right now I have to apply some dirty hacks. Hacks make behavior confusing: https://github.com/hintron/computer-enhance/issues/35
This pull request introduces a new behavior: now `rustc` will emit a new artifact notification for every artifact type user asked to `--emit`, for example for `--emit asm` those will include all the `.s` files.
Most users won't notice this behavior, to be affected by it all of the following must hold:
- user must use `rustc` binary directly (when `cargo` invokes `rustc` - it consumes artifact notifications and doesn't emit anything)
- user must specify both `--emit xxx` and `--json artifacts`
- user must refuse to handle unknown artifact types
- user must disable incremental compilation (or deal with it better than cargo does, or use a workaround like `save-temps`) in order not to hit #88829 / #89149
This commit sets the `target_env` key for the
`wasm32-wasi{,p1,p1-threads}` targets to the string `"p1"`. This mirrors
how the `wasm32-wasip2` target has `target_env = "p2"`. The intention of
this is to more easily detect each target in downstream crates to enable
adding custom code per-target.
cc #125803
Refactor documentation for Apple targets
Refactor the documentation for Apple targets in `rustc`'s platform support page to make it clear what the supported OS version is and which environment variables are being read (`*_DEPLOYMENT_TARGET` and `SDKROOT`). This fixes https://github.com/rust-lang/rust/issues/124215.
Note that I've expanded the `aarch64-apple-ios-sim` maintainers `@badboy` and `@deg4uss3r` to include being maintainer of all `*-apple-ios-*` targets. If you do not wish to be so, please state that, then I'll explicitly note that in the docs.
Additionally, I've added myself as co-maintainer of most of these targets.
r? `@thomcc`
I think the documentation you've previously written on tvOS is great, have mostly modified it to have a more consistent formatting with the rest of the Apple target.
I recognize that there's quite a few changes here, feel free to ask about any of them!
---
CC `@simlay` `@Nilstrieb`
`@rustbot` label O-apple
Add x86_64-unknown-linux-none target
Adds a freestanding linux binary with no libc dependency. This is useful for writing programs written only in rust. It is also essential for writing low level stuff like libc or a dynamic linker.
Tier 3 policy:
>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.)
I will be the designed maintainer for this target
>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.
The target triple is consistent with other targets
>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.
There is no confusion with other targets since it explicitly adds "none" at the end instead of omitting the environment
>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 does not introduce any unusual requirement
>The target must not introduce license incompatibilities.
There are no license incompatibilities
> Anything added to the Rust repository must be under the standard Rust license (MIT OR Apache-2.0).
Everything added is under that license
>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 be subject to any new license requirements.
There are no new dependencies
>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.
There is no proprietary dependencies
>"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.
No such terms exist for this target
>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.
Understood
>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.
The target already implements core. It might be possible in the future to add support for alloc and std by leveraging crates such as [origin](https://github.com/sunfishcode/origin/) and [rustix](https://github.com/bytecodealliance/rustix)
> 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.
I believe the proper docs are added
>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.
Understood
> 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.
No other targets are effected
>Tier 3 targets must be able to produce assembly using at least one of rustc's supported backends from any host target.
The same backends used by other linux targets work without issues
This commit fixes several issues in the fuchsia-test-runner.py script:
1. Migrate from `pm` to `ffx` for package management, as `pm` is now
deprecated. Furthermore, the `pm` calls used in this script no longer
work at Fuchsia's HEAD. This is the largest change in this commit, and
impacts all steps around repository management (creation and
registration of the repo, as well as package publishing).
2. Allow for `libtest` to be either statically or dynamically linked.
The script assumed it was dynamically linked, but the current Rust
behavior at HEAD is to statically link it.
3. Minor cleanup to use `ffx --machine json` rather than string parsing.
4. Minor cleanup to the docs around the script.
Make check-cfg docs more user-friendly
This PR improves the `--check-cfg` to make them more user-friendly by:
- explaining the purpose of the feature
- removing the "form" jargon
- making it (bit) less formal and more "friendly"
- making the doc less cluttered
- and by fixing (the width and flags) of the examples
`@rustbot` label +F-check-cfg
