tests: add sanity-check assembly test for every target
Fixes#119910.
Adds a basic assembly test checking that each target can produce assembly and update the target tier policy to require this.
cc rust-lang/compiler-team#655
r? `@wesleywiser`
Add way to express that no values are expected with check-cfg
This PR adds way to express no-values (no values expected) with `--check-cfg` by making empty `values()` no longer mean `values(none())` (internal: `&[None]`) and now be an empty list (internal: `&[]`).
### Context
Currently `--check-cfg` has a way to express that _any value is expected_ with `values(any())`, but has no way to do the inverse and say that _no value is expected_.
This would be particularly useful for build systems that control a config name and it's values as they could always declare a config name as expected and if in the current state they have values pass them and if not pass an empty list.
To give a more concrete example, Cargo `--check-cfg` currently needs to generate:
- `--check-cfg=cfg(feature, values(...))` for the case with declared features
- and `--check-cfg=cfg()` for the case without any features declared
This means that when there are no features declared, users will get an `unexpected config name` but from the point of view of Cargo the config name `feature` is expected, it's just that for now there aren't any values for it.
See [Cargo `check_cfg_args` function](92395d9010/src/cargo/core/compiler/mod.rs (L1263-L1281)) for more details.
### De-specializing *empty* `values()`
To solve this issue I propose that we "de-specialize" empty `values()` to no longer mean `values(none())` but to actually mean empty set/list. This is one of the last source of confusion for my-self and others with the `--check-cfg` syntax.
> The confusing part here is that an empty `values()` currently means the same as `values(none())`, i.e. an expected list of values with the _none_ variant (as in `#[cfg(name)]` where the value is none) instead of meaning an empty set.
Before the new `cfg()` syntax, defining the _none_ variant was only possible under certain circumstances, so in https://github.com/rust-lang/rust/pull/111068 I decided to make `values()` to mean the _none_ variant, but it is no longer necessary since https://github.com/rust-lang/rust/pull/119473 which introduced the `none()` syntax.
A simplified representation of the proposed "de-specialization" would be:
| Syntax | List/set of expected values |
|-----------------------------------------|-----------------------------|
| `cfg(name)`/`cfg(name, values(none()))` | `&[None]` |
| `cfg(name, values())` | `&[]` |
Note that I have my-self made the mistake of using an empty `values()` as meaning empty set, see https://github.com/rust-lang/cargo/pull/13011.
`@rustbot` label +F-check-cfg
r? `@petrochenkov`
cc `@epage`
Adds a basic assembly test checking that each target can produce assembly
and update the target tier policy to require this.
Signed-off-by: David Wood <david@davidtw.co>
Add explicit `none()` value variant in check-cfg
This PR adds an explicit none value variant in check-cfg values: `values(none())`.
Currently the only way to define the none variant is with an empty `values()` which means that if someone has a cfg that takes none and strings they need to use two invocations: `--check-cfg=cfg(foo) --check-cfg=cfg(foo, values("bar"))`.
Which would now be `--check-cfg=cfg(foo, values(none(),"bar"))`, this is simpler and easier to understand.
`--check-cfg=cfg(foo)`, `--check-cfg=cfg(foo, values())` and `--check-cfg=cfg(foo, values(none()))` would be equivalent.
*Another motivation for doing this is to make empty `values()` actually means no-values, but this is orthogonal to this PR and adding `none()` is sufficient in it-self.*
`@rustbot` label +F-check-cfg
r? `@petrochenkov`
Use version-sorting for all sorting
Add a description of a version-sorting algorithm. (This algorithm does
not precisely match `strverscmp`; it's intentionally simpler in its
handling of leading zeroes, and produces a result easier for humans to
easily understand and do by hand.)
Change all references to sorting to use version-sorting.
Change all references to "ASCIIbetically" to instead say "sort
non-lowercase before lowercase".
Rework and improve the unstable documentation of check-cfg
This PR rework and improve the unstable documentation of the check-cfg feature.
The goal is to have a simpler to understand documentation with examples that are more practical and less theoretical. As well as making the documentation more explicit about the whereabouts of the feature.
`@rustbot` label +T-compiler +F-check-cfg
merge core_panic feature into panic_internals
I don't know why those are two separate features, but it does not seem intentional. This merge is useful because with https://github.com/rust-lang/rust/pull/118123, panic_internals is recognized as an internal feature, but core_panic is not -- but core_panic definitely should be internal.
rustdoc: search for tuples and unit by type with `()`
This feature extends rustdoc to support the syntax that most users will naturally attempt to use to search for tuples. Part of https://github.com/rust-lang/rust/issues/60485
Function signature searches already support tuples and unit. The explicit name `primitive:tuple` and `primitive:unit` can be used to match a tuple or unit, while `()` will match either one. It also follows the direction set by the actual language for parens as a group, so `(u8,)` will only match a tuple, while `(u8)` will match a plain, unwrapped byte—thanks to loose search semantics, it will also match the tuple.
## Preview
* [`option<t>, option<u> -> (t, u)`](<https://notriddle.com/rustdoc-html-demo-5/tuple-unit/std/index.html?search=option%3Ct%3E%2C option%3Cu%3E -%3E (t%2C u)>)
* [`[t] -> (t,)`](<https://notriddle.com/rustdoc-html-demo-5/tuple-unit/std/index.html?search=[t] -%3E (t%2C)>)
* [`(ipaddr,) -> socketaddr`](<https://notriddle.com/rustdoc-html-demo-5/tuple-unit/std/index.html?search=(ipaddr%2C) -%3E socketaddr>)
## Motivation
When type-based search was first landed, it was directly [described as incomplete][a comment].
[a comment]: https://github.com/rust-lang/rust/pull/23289#issuecomment-79437386
Filling out the missing functionality is going to mean adding support for more of Rust's [type expression] syntax, such as tuples (in this PR), references, raw pointers, function pointers, and closures.
[type expression]: https://doc.rust-lang.org/reference/types.html#type-expressions
There does seem to be demand for this sort of thing, such as [this Discord message](https://discord.com/channels/442252698964721669/443150878111694848/1042145740065099796) expressing regret at rustdoc not supporting tuples in search queries.
## Reference description (from the Rustdoc book)
<table>
<thead>
<tr>
<th>Shorthand</th>
<th>Explicit names</th>
</tr>
</thead>
<tbody>
<tr><td colspan="2">Before this PR</td></tr>
<tr>
<td><code>[]</code></td>
<td><code>primitive:slice</code> and/or <code>primitive:array</code></td>
</tr>
<tr>
<td><code>[T]</code></td>
<td><code>primitive:slice<T></code> and/or <code>primitive:array<T></code></td>
</tr>
<tr>
<td><code>!</code></td>
<td><code>primitive:never</code></td>
</tr>
<tr><td colspan="2">After this PR</td></tr>
<tr>
<td><code>()</code></td>
<td><code>primitive:unit</code> and/or <code>primitive:tuple</code></td>
</tr>
<tr>
<td><code>(T)</code></td>
<td><code>T</code></td>
</tr>
<tr>
<td><code>(T,)</code></td>
<td><code>primitive:tuple<T></code></td>
</tr>
</tbody>
</table>
A single type expression wrapped in parens is the same as that type expression, since parens act as the grouping operator. If they're empty, though, they will match both `unit` and `tuple`, and if there's more than one type (or a trailing or leading comma) it is the same as `primitive:tuple<...>`.
However, since items can be left out of the query, `(T)` will still return results for types that match tuples, even though it also matches the type on its own. That is, `(u32)` matches `(u32,)` for the exact same reason that it also matches `Result<u32, Error>`.
## Future direction
The [type expression grammar](https://doc.rust-lang.org/reference/types.html#type-expressions) from the Reference is given below:
<pre><code>Syntax
Type :
TypeNoBounds
| <a href="https://doc.rust-lang.org/reference/types/impl-trait.html">ImplTraitType</a>
| <a href="https://doc.rust-lang.org/reference/types/trait-object.html">TraitObjectType</a>
<br>
TypeNoBounds :
<a href="https://doc.rust-lang.org/reference/types.html#parenthesized-types">ParenthesizedType</a>
| <a href="https://doc.rust-lang.org/reference/types/impl-trait.html">ImplTraitTypeOneBound</a>
| <a href="https://doc.rust-lang.org/reference/types/trait-object.html">TraitObjectTypeOneBound</a>
| <a href="https://doc.rust-lang.org/reference/paths.html#paths-in-types">TypePath</a>
| <a href="https://doc.rust-lang.org/reference/types/tuple.html#tuple-types">TupleType</a>
| <a href="https://doc.rust-lang.org/reference/types/never.html">NeverType</a>
| <a href="https://doc.rust-lang.org/reference/types/pointer.html#raw-pointers-const-and-mut">RawPointerType</a>
| <a href="https://doc.rust-lang.org/reference/types/pointer.html#shared-references-">ReferenceType</a>
| <a href="https://doc.rust-lang.org/reference/types/array.html">ArrayType</a>
| <a href="https://doc.rust-lang.org/reference/types/slice.html">SliceType</a>
| <a href="https://doc.rust-lang.org/reference/types/inferred.html">InferredType</a>
| <a href="https://doc.rust-lang.org/reference/paths.html#qualified-paths">QualifiedPathInType</a>
| <a href="https://doc.rust-lang.org/reference/types/function-pointer.html">BareFunctionType</a>
| <a href="https://doc.rust-lang.org/reference/macros.html#macro-invocation">MacroInvocation</a>
</code></pre>
ImplTraitType and TraitObjectType (and ImplTraitTypeOneBound and TraitObjectTypeOneBound) are not yet implemented. They would mostly desugar to `trait:`, similarly to how `!` desugars to `primitive:never`.
ParenthesizedType and TuplePath are added in this PR.
TypePath is already implemented (except const generics, which is not planned, and function-like trait syntax, which is planned as part of closure support).
NeverType is already implemented.
RawPointerType and ReferenceType require parsing and fixes to the search index to store this information, but otherwise their behavior seems simple enough. Just like tuples and slices, `&T` would be equivalent to `primitive:reference<T>`, `&mut T` would be equivalent to `primitive:reference<keyword:mut, T>`, `*T` would be equivalent to `primitive:pointer<T>`, `*mut T` would be equivalent to `primitive:pointer<keyword:mut, T>`, and `*const T` would be equivalent to `primitive:pointer<keyword:const, T>`. Lifetime generics support is not planned, because lifetime subtyping seems too complicated.
ArrayType is subsumed by SliceType right now. Implementing const generics is not planned, because it seems like it would require a lot of implementation complexity for not much gain.
InferredType isn't really covered right now. Its semantics in a search context are not obvious.
QualifiedPathInType is not implemented, and it is not planned. I would need a use case to justify it, and act as a guide for what the exact semantics should be.
BareFunctionType is not implemented. Along with function-like trait syntax, which is formally considered a TypePath, it's the biggest missing feature to be able to do structured searches over generic APIs like `Option`.
MacroInvocation is not parsed (macro names are, but they don't mean the same thing here at all). Those are gone by the time Rustdoc sees the source code.
Move `i586-unknown-netbsd` from tier 2 to tier 3 platform support table
It appears it was intended to be tier 3, but was accidentally added to tier 2. Based on inspecting the PR adding it the table https://github.com/rust-lang/rust/pull/117170 and the fact that it is not built in CI which is one of the tier 2 requirements.
cc ````@he32````
r? ````@Nilstrieb````
Support reg_addr register class in s390x inline assembly
In s390x, `r0` cannot be used as an address register (it is evaluated as zero in an address context).
Therefore, currently, in assemblies involving memory accesses, `r0` must be [marked as clobbered](1a1155653a/src/arch/s390x.rs (L58)) or [explicitly used to a non-address](1a1155653a/src/arch/s390x.rs (L135)) or explicitly use an address register to prevent `r0` from being allocated to a register for the address.
This patch adds a register class for allocating general-purpose registers, except `r0`, to make it easier to use address registers. (powerpc already has a register class (reg_nonzero) for a similar purpose.)
This is identical to the `a` constraint in LLVM and GCC:
https://llvm.org/docs/LangRef.html#supported-constraint-code-list
> a: A 32, 64, or 128-bit integer address register (excludes R0, which in an address context evaluates as zero).
https://gcc.gnu.org/onlinedocs/gcc/Machine-Constraints.html
> a
> Address register (general purpose register except r0)
cc ``@uweigand``
r? ``@Amanieu``
rework `-Zverbose`
implements the changes described in https://github.com/rust-lang/compiler-team/issues/706
the first commit is only a name change from `-Zverbose` to `-Zverbose-internals` and does not change behavior. the second commit changes diagnostics.
possible follow up work:
- `ty::pretty` could print more info with `--verbose` than it does currently. `-Z verbose-internals` shows too much info in a way that's not helpful to users. michael had ideas about this i didn't fully understand: https://rust-lang.zulipchat.com/#narrow/stream/233931-t-compiler.2Fmajor-changes/topic/uplift.20some.20-Zverbose.20calls.20and.20rename.20to.E2.80.A6.20compiler-team.23706/near/408984200
- `--verbose` should imply `-Z write-long-types-to-disk=no`. the code in `ty_string_with_limit` should take `--verbose` into account (apparently this affects `Ty::sort_string`, i'm not familiar with this code). writing a file to disk should suggest passing `--verbose`.
r? `@compiler-errors` cc `@estebank`
Add illumos aarch64 target for rust.
This adds the newly being developed illumos aarch64 target to the rust compiler.
`@rmustacc` `@citrus-it` `@richlowe` As promissed before my hiatus :)
Treat numeric chunks with equal value but differing numbers of leading
zeroes as equal, unless we get to the end of the entire string in which
case we use "more leading zeroes in the earliest differing chunk" as a
tiebreaker.
Treat `_` as a word separator, sorting it before anything other than
space.
Give more examples.
Add arm-none-eabi and armv7r-none-eabi platform-support documentation.
Mostly collecting existing information that's common to all arm-none-eabi targets and putting it in one file and adding a new file with specific details about armv7r.
Update books
## rust-lang/edition-guide
2 commits in 34fca48ed284525b2f124bf93c51af36d6685492..bbffb074e16bef89772818b400b6c76a65eac126
2023-12-11 18:46:08 UTC to 2023-12-06 21:38:11 UTC
- Update links and text about rustfix. (rust-lang/edition-guide#287)
- Add C-string literals. (rust-lang/edition-guide#286)
## rust-embedded/book
1 commits in 22bca3d0f6e9b9b556689b54ce96f25b46ecd1b3..3f9df2b9885c6741365da2e12ed6662cd0e827d6
2023-12-11 21:22:20 UTC to 2023-12-11 21:22:20 UTC
- #363 (rust-embedded/book#364)
## rust-lang/nomicon
2 commits in 83d015105e6d490fc30d6c95da1e56152a50e228..f6bd083c4ccfc4ce6699b8b4154e3c45c5a27a8c
2023-12-10 03:19:24 UTC to 2023-12-10 03:18:32 UTC
- Minor improvements to Vec (rust-lang/nomicon#415)
- Improve the `PhantomData` table (rust-lang/nomicon#417)
## rust-lang/reference
1 commits in 692d216f5a1151e8852ddb308ba64040e634c876..f9f5b5babd95515e7028c32d6ca4d9790f64c146
2023-12-10 16:16:17 UTC to 2023-12-10 16:16:17 UTC
- Document object unsafety of async-fn-in-trait (rust-lang/reference#1435)
## rust-lang/rust-by-example
11 commits in da0a06aada31a324ae84a9eaee344f6a944b9683..4c2b24ff9d9cf19f2fcff799a3a49b9a2c50ae8e
2023-12-18 13:02:23 UTC to 2023-12-10 12:10:43 UTC
- nested destructure example for structs (rust-lang/rust-by-example#1787)
- Make example in pipe.md compatible with both Windows and Unix-type system with less code (rust-lang/rust-by-example#1780)
- Add i18n support (rust-lang/rust-by-example#1760)
- Add pub keyword before mod bar definition in doc.md (rust-lang/rust-by-example#1785)
- Update address and title of github source of rust playground in playground.md (rust-lang/rust-by-example#1784)
- Update example in ffi.md to make it compatible with both Windows OS and Unit-type systems (rust-lang/rust-by-example#1781)
- Update the path of html_playground_url in playground.md (rust-lang/rust-by-example#1783)
- Update unit_testing.md ignore running the last example because it's test (rust-lang/rust-by-example#1782)
- Update example in fs.md and use target_family instead of target_os (rust-lang/rust-by-example#1779)
- Update the example in pipe.md to make it compatible with both Windows OS and Unix-type systems (rust-lang/rust-by-example#1778)
- Update the example in fs.md to ensure compatibility with both Window and Unix-type systems. (rust-lang/rust-by-example#1777)
## rust-lang/rustc-dev-guide
7 commits in 904bb5aa7b21adad58ffae610e2830c7b0f813b0..0610665a8687b1b0aa037917a1598b9f2a21e3ef
2023-12-17 17:21:38 UTC to 2023-12-05 16:40:26 UTC
- add a mailmap (rust-lang/rustc-dev-guide#1839)
- Move Editions chapter to "Contributing to Rust". (rust-lang/rustc-dev-guide#1838)
- Remove feature edition fields. (rust-lang/rustc-dev-guide#1836)
- Add a chapter on editions. (rust-lang/rustc-dev-guide#1835)
- Remove mentions of plugin lints (rust-lang/rustc-dev-guide#1833)
- Fix typo of unused_parens (rust-lang/rustc-dev-guide#1832)
- Replace experts map with reviewers from triagebot (rust-lang/rustc-dev-guide#1831)
Add new tier 3 aarch64-apple-watchos target
Apple Xcode 14/15 releases add a new apple watchos target architecture arm64 out of arm64_32 and armv7k, now add a new tier 3 target support for this target.
### Tier 3 Target Requirements
Adds support for Apple WatchOS aarch64-apple-watchos target.
Below are details on how this target meets the requirements for tier 3:
> 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.)
`@leohowell` has volunteered to be the target maintainer. I am also happy to help if a second maintainer is required.
> 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.
Uses the same naming as the LLVM target, and the same convention as other Apple 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.
I don't believe there is any ambiguity here.
> 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.
I don't see any legal issues here.
> 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 be subject to any new license requirements.
> If the target supports building host tools (such as rustc or cargo), those host tools must not depend on proprietary (non-FOSS) libraries, other than ordinary runtime libraries supplied by the platform and commonly used by other binaries built for the target. 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.
> Targets should not require proprietary (non-FOSS) components to link a functional binary or library.
> "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.
I see no issues with any of the above.
> 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.
Only relevant to those making approval decisions.
> 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.
core and alloc can be used. std support will be added in a subsequent PR.
> 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 tests (even if they do not pass), the documentation must explain how to run tests for the target, using emulation if possible or dedicated hardware if necessary.
Use --target= option to cross compile, just like any target. Tests can be run using the WatchOS simulator (see https://developer.apple.com/documentation/xcode/running-your-app-in-the-simulator-or-on-a-device).
> 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.
I don't foresee this being a problem.
> 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 by the pull request.
r? compiler-team