fix ICE when suggesting `::new`
fixes https://github.com/rust-lang/rust/issues/146174
This code suggests to write `Foo::new(...)` when the user writes `Foo(...)` or `Foo { ... }` and the constructor is private, where `new` is some associated function that returns `Self`.
When checking that the return type of `new` is `Self`, we need to instantiate the parameters of `new` with infer vars, so we don't end up with a type like `Box<$param(0)>` in a context that doesn't have any parameters. But then we can't use `normalize_erasing_late_bound_regions` anymore because that goes though a query that can't deal with infer vars.
Since this is diagnostic-only code that is supposed to check for exactly `-> Self`, I think it's fine to just skip normalizing here, especially since The Correct Way<sup>TM</sup> would involve a probe and make this code even more complicated.
Also, the code here does almost the same thing, and these suggestions can probably be unified in the future: 4ca8078d37/compiler/rustc_hir_typeck/src/method/suggest.rs (L2123-L2129)
r? ````@compiler-errors````
cc ````@Qelxiros```` -- this should unblock https://github.com/rust-lang/rust/pull/144420
Sanitizers target modificators
Depends on bool flag fix: https://github.com/rust-lang/rust/pull/138483.
Some sanitizers need to be target modifiers, and some do not. For now, we should mark all sanitizers as target modifiers except for these: AddressSanitizer, LeakSanitizer
For kCFI, the helper flag -Zsanitizer-cfi-normalize-integers should also be a target modifier.
Many test errors was with sanizer flags inconsistent with std deps. Tests are fixed with `-C unsafe-allow-abi-mismatch`.
Allow `inline(always)` with a target feature behind a unstable feature `target_feature_inline_always`.
Rather than adding the inline always attribute to the function definition, we add it to the callsite. We can then check that the target features match and that the call would be safe to inline. If the function isn't inlined due to a mismatch, we emit a warning informing the user that the function can't be inlined due to the target feature mismatch.
See tracking issue rust-lang/rust#145574
On unused binding or binding not present in all patterns, suggest potential typo of unit struct/variant or const
When encountering an or-pattern with a binding not available in all patterns, look for consts and unit struct/variants that have similar names as the binding to detect typos.
```
error[E0408]: variable `Ban` is not bound in all patterns
--> $DIR/binding-typo.rs:22:9
|
LL | (Foo, _) | (Ban, Foo) => {}
| ^^^^^^^^ --- variable not in all patterns
| |
| pattern doesn't bind `Ban`
|
help: you might have meant to use the similarly named unit variant `Bar`
|
LL - (Foo, _) | (Ban, Foo) => {}
LL + (Foo, _) | (Bar, Foo) => {}
|
```
For items that are not in the immedate scope, suggest the full path for them:
```
error[E0408]: variable `Non` is not bound in all patterns
--> $DIR/binding-typo-2.rs:51:16
|
LL | (Non | Some(_))=> {}
| --- ^^^^^^^ pattern doesn't bind `Non`
| |
| variable not in all patterns
|
help: you might have meant to use the similarly named unit variant `None`
|
LL - (Non | Some(_))=> {}
LL + (core::option::Option::None | Some(_))=> {}
|
```
When encountering a typo in a pattern that gets interpreted as an unused binding, look for unit struct/variant of the same type as the binding:
```
error: unused variable: `Non`
--> $DIR/binding-typo-2.rs:36:9
|
LL | Non => {}
| ^^^
|
help: if this is intentional, prefix it with an underscore
|
LL | _Non => {}
| +
help: you might have meant to pattern match on the similarly named variant `None`
|
LL - Non => {}
LL + std::prelude::v1::None => {}
|
```
Suggest constant on unused binding in a pattern
```
error: unused variable: `Batery`
--> $DIR/binding-typo-2.rs:110:9
|
LL | Batery => {}
| ^^^^^^
|
help: if this is intentional, prefix it with an underscore
|
LL | _Batery => {}
| +
help: you might have meant to pattern match on the similarly named constant `Battery`
|
LL | Battery => {}
| +
```
Fixrust-lang/rust#51976.
fix drop scope for `super let` bindings within `if let`
Fixesrust-lang/rust#145328 by making non-lifetime-extended `super let` reuse the logic used to compute drop scopes for non-lifetime-extended temporaries.
Also fixesrust-lang/rust#145374, which regressed due to rust-lang/rust#143376 introducing `if let`-like scopes for match arms with guards.
Tracking issue for `super let`: rust-lang/rust#139076
This is a regression fix / breaking change for macros stably exposing `super let`, including `pin!` and `format_args!`.
Nominating to be discussed alongside rust-lang/rust#145328: ```@rustbot``` label +I-lang-nominated +I-libs-api-nominated
a more general version of https://github.com/rust-lang/rust/pull/146080.
after a bit of hacking in [`fluent.rs`](https://github.com/rust-lang/rust/blob/master/compiler/rustc_fluent_macro/src/fluent.rs), i discovered that i'm not the only one that is bad at following guidelines 😅. this pr lowercases the first letter of all the error messages in the codebase.
(i did not change things that are traditionally uppercased such as _MIR_, _ABI_ or _C_)
i think it's reasonable to run a `@bors try` so all the test suite is checked, as i cannot run some of the tests on my machine. i double checked (and replaced manually) all the old error messages, but better be safe than sorry.
in the future i will try to add a check in `x test tidy` that errors if an error message starts with an uppercase letter.
fix(lexer): Only allow horizontal whitespace in frontmatter
In writing up the reference for frontmatter, I realized that we probably
shouldn't be accepting Unicode Line Ending characters between the code
fence and infostring or trailing after the infostring or a code fence.
In digging into the unicode specification we use for Whitespace, it
divides it up into categories, so I'm deferring to what it says for
horizontal whitespace for what should be used within a line.
Note, I am leaving out support for Unicode Default Ignorable characters.
I figure that can be discussed outside of this change within the
reference and tracking issue.
Fixesrust-lang/rust#145971
Frontmatter tracking issue: rust-lang/rust#136889
Constify conversion traits (part 1)
This is the first part of rust-lang/rust#144289 being split into smaller pieces. It adds/moves constness of several traits under the `const_convert` feature:
* `From`
* `Into`
* `TryFrom`
* `TryInto`
* `FromStr`
* `AsRef`
* `AsMut`
* `Borrow`
* `BorrowMut`
* `Deref`
* `DerefMut`
There are a few methods that are intrinsically tied to these traits which I've included in the feature. Particularly, those which are wrappers over `AsRef`:
* `ByteStr::new` (unstable under `bstr` feature)
* `OsStr::new`
* `Path::new`
Those which directly use `Into`:
* `Result::into_ok`
* `Result::into_err`
And those which use `Deref` and `DerefMut`:
* `Pin::as_ref`
* `Pin::as_mut`
* `Pin::as_deref_mut`
* `Option::as_deref`
* `Option::as_deref_mut`
* `Result::as_deref`
* `Result::as_deref_mut`
(note: the `Option` and `Result` methods were suggested by ``@npmccallum`` initially as rust-lang/rust#146101)
The parts which are missing from this PR are:
* Anything that involves heap-allocated types
* Making any method const than the ones listed above
* Anything that could rely on the above, *or* could rely on system-specific code for `OsStr` or `Path` (note: this mostly makes these methods useless since `str` doesn't implement `AsRef<OsStr>` yet, but it's better to track the method for now and add impls later, IMHO)
r? ``@tgross35`` (who mostly already reviewed this)
Add compiler error when trying to use concat metavar expr in repetitions
## Disclaimer
This is my first PR to rust, so if I missed/could improve something about this PR, please excuse and tell me!
## The improvement
The [metavar_expr_concat feature](https://github.com/rust-lang/rust/issues/124225) currently does not seem to support nested repetitions, and throws an ICE without much explanation if the relevant code path is hit.
This PR adds a draft compiler error that attempts to explain the issue. I am not 100% sure what all the ways of triggering this error are, so the message is currently pretty generic, please do correct me if there's something wrong with it or it could be improved.
Thank you for you time!
Fixesrust-lang/rust#140479.
add span to struct pattern rest (..)
Struct pattern rest (`..`) did not retain span information compared to normal fields. This patch adds span information for it.
The motivation of this patch comes from when I implemented this PR for Clippy: https://github.com/rust-lang/rust-clippy/pull/15000#discussion_r2134145163
It is possible to get the span of the Et cetera in a bit roundabout way, but I thought this would be nicer.
stabilize c-style varargs for sysv64, win64, efiapi, aapcs
This has been split up so the PR now only contains the extended_varargs_abi_support stabilization; "system" has been moved to https://github.com/rust-lang/rust/pull/145954.
**Previous (combined) PR description:**
This stabilizes extern block declarations of variadic functions with the system, sysv64, win64, efiapi, aapcs ABIs. This corresponds to the extended_varargs_abi_support and extern_system_varargs feature gates.
The feature gates were split up since it seemed like there might be further discussion needed for what exactly "system" ABI variadic functions should do, but a [consensus](https://github.com/rust-lang/rust/issues/136946#issuecomment-2967847553) has meanwhile been reached: they shall behave like "C" functions. IOW, the ABI of a "system" function is (bold part is new in this PR):
- "stdcall" for win32 targets **for non-variadic functions**
- "C" for everything else
This had been previously stabilized *without FCP* in https://github.com/rust-lang/rust/pull/116161, which got reverted in https://github.com/rust-lang/rust/pull/136897. There was also a "fun" race condition involved with the system ABI being [added](https://github.com/rust-lang/rust/pull/119587) to the list of variadic-supporting ABIs between the creation and merge of rust-lang/rust#116161.
There was a question raised [here](https://github.com/rust-lang/rust/pull/116161#issuecomment-1983829513) whether t-lang even needs to be involved for a change like this. Not sure if that has meanwhile been clarified? The behavior of the "system" ABI (a Rust-specific ABI) definitely feels like t-lang territory to me.
Fixesrust-lang/rust#100189
Cc `@rust-lang/lang`
# Stabilization report
> ## General design
> ### What is the RFC for this feature and what changes have occurred to the user-facing design since the RFC was finalized?
AFAIK there is no RFC. The tracking issues are
- https://github.com/rust-lang/rust/issues/100189
- https://github.com/rust-lang/rust/issues/136946
> ### What behavior are we committing to that has been controversial? Summarize the major arguments pro/con.
The only controversial point is whether "system" ABI functions should support variadics.
- Pro: This allows crates like windows-rs to consistently use "system", see e.g. https://github.com/microsoft/windows-rs/issues/3626.
- Cons: `@workingjubilee` had some implementation concerns, but I think those have been [resolved](https://github.com/rust-lang/rust/issues/136946#issuecomment-2967847553). EDIT: turns out Jubilee still has concerns (she mentioned that in a DM); I'll let her express those.
Note that "system" is already a magic ABI we introduced to "do the right thing". This just makes it do the right thing in more cases. In particular, it means that on Windows one can almost always just do
```rust
extern "system" {
// put all the things here
}
```
and it'll do the right thing, rather than having to split imports into non-varargs and varargs, with the varargs in a separate `extern "C"` block (and risking accidentally putting a non-vararg there).
(I am saying "almost" always because some Windows API functions actually use cdecl, not stdcall, on x86. Those of course need to go in `extern "C"` blocks.)
> ### Are there extensions to this feature that remain unstable? How do we know that we are not accidentally committing to those?
Actually defining variadic functions in Rust remains unstable, under the [c_variadic feature gate](https://github.com/rust-lang/rust/issues/44930).
> ## Has a Call for Testing period been conducted? If so, what feedback was received?
>
> Does any OSS nightly users use this feature? For instance, a useful indication might be "search <grep.app> for `#![feature(FEATURE_NAME)]` and had `N` results".
There was no call for testing.
A search brings up https://github.com/rust-osdev/uefi-rs/blob/main/uefi-raw/src/table/boot.rs using this for "efiapi". This doesn't seem widely used, but it is an "obvious" gap in our support for c-variadics.
> ## Implementation quality
All rustc does here is forward the ABI to LLVM so there's lot a lot to say here...
> ### Summarize the major parts of the implementation and provide links into the code (or to PRs)
>
> An example for async closures: <https://rustc-dev-guide.rust-lang.org/coroutine-closures.html>.
The check for allowed variadic ABIs is [here](9c870d30e2/compiler/rustc_hir_analysis/src/lib.rs (L109-L126)).
The special handling of "system" is [here](c24914ec83/compiler/rustc_target/src/spec/abi_map.rs (L82-L85)).
> ### Summarize existing test coverage of this feature
>
> Consider what the "edges" of this feature are. We're particularly interested in seeing tests that assure us about exactly what nearby things we're not stabilizing.
>
> Within each test, include a comment at the top describing the purpose of the test and what set of invariants it intends to demonstrate. This is a great help to those reviewing the tests at stabilization time.
>
> - What does the test coverage landscape for this feature look like?
> - Tests for compiler errors when you use the feature wrongly or make mistakes?
> - Tests for the feature itself:
> - Limits of the feature (so failing compilation)
> - Exercises of edge cases of the feature
> - Tests that checks the feature works as expected (where applicable, `//@ run-pass`).
> - Are there any intentional gaps in test coverage?
>
> Link to test folders or individual tests (ui/codegen/assembly/run-make tests, etc.).
Prior PRs add a codegen test for all ABIs and tests actually calling extern variadic functions for sysv64 and win64:
- https://github.com/rust-lang/rust/pull/144359
- https://github.com/rust-lang/rust/pull/144379
We don't have a way of executing uefi target code in the test suite, so it's unclear how to fully test efiapi. aapcs could probably be done? (But note that we have hardly an such actually-calling-functions tests for ABI things, we almost entirely rely on codegen tests.)
The test ensuring that we do *not* stabilize *defining* c-variadic functions is `tests/ui/feature-gates/feature-gate-c_variadic.rs`.
> ### What outstanding bugs in the issue tracker involve this feature? Are they stabilization-blocking?
None that I am aware of.
> ### What FIXMEs are still in the code for that feature and why is it ok to leave them there?
None that I am aware of.
> ### Summarize contributors to the feature by name for recognition and assuredness that people involved in the feature agree with stabilization
`@Soveu` added sysv64, win64, efiapi, aapcs to the list of ABIs that allow variadics, `@beepster4096` added system. `@workingjubilee` recently refactored the ABI handling in the compiler, also affecting this feature.
> ### Which tools need to be adjusted to support this feature. Has this work been done?
>
> Consider rustdoc, clippy, rust-analyzer, rustfmt, rustup, docs.rs.
Maybe RA needs to be taught about the new allowed ABIs? No idea how precisely they mirror what exactly rustc accepts and rejects here.
> ## Type system and execution rules
> ### What compilation-time checks are done that are needed to prevent undefined behavior?
>
> (Be sure to link to tests demonstrating that these tests are being done.)
Nothing new here, this just expands the existing support for calling variadic functions to more ABIs.
> ### Does the feature's implementation need checks to prevent UB or is it sound by default and needs opt in in places to perform the dangerous/unsafe operations? If it is not sound by default, what is the rationale?
Nothing new here, this just expands the existing support for calling variadic functions to more ABIs.
> ### Can users use this feature to introduce undefined behavior, or use this feature to break the abstraction of Rust and expose the underlying assembly-level implementation? (Describe.)
Nothing new here, this just expands the existing support for calling variadic functions to more ABIs.
> ### What updates are needed to the reference/specification? (link to PRs when they exist)
- https://github.com/rust-lang/reference/pull/1936
> ## Common interactions
> ### Does this feature introduce new expressions and can they produce temporaries? What are the lifetimes of those temporaries?
No.
> ### What other unstable features may be exposed by this feature?
None.
`-Znext-solver`: support non-defining uses in closures
Cleaned up version of rust-lang/rust#139587, finishing the implementation of https://github.com/rust-lang/types-team/issues/129. This does not affect stable. The reasoning for why this is the case is subtle however.
## What does it do
We split `do_mir_borrowck` into `borrowck_collect_region_constraints` and `borrowck_check_region_constraints`, where `borrowck_collect_region_constraints` returns an enormous `CollectRegionConstraintsResult` struct which contains all the relevant data to actually handle opaque type uses and to check the region constraints later on.
`query mir_borrowck` now simply calls `BorrowCheckRootCtxt::do_mir_borrowck` which starts by iterating over all nested bodies of the current function - visiting nested bodies before their parents - and computing their `CollectRegionConstraintsResult`.
After we've collected all constraints it's time to actually compute the concrete types for the opaques defined by this function. With this PR we now compute the concrete types of opaques for each body before using them to check the non-defining uses of any of them.
After we've computed the concrete types by using all bodies, we use `apply_computed_concrete_opaque_types` for each body to constrain non-defining uses, before finally finishing with `borrowck_check_region_constraints`. We always visit nested bodies before their parents when doing this.
## `ClosureRegionRequirements`
As we only call `borrowck_collect_region_constraints` for nested bodies before type checking the parent, we can't simply use the final `ClosureRegionRequirements` of the nested body during MIR type check. We instead track that we need to apply these requirements in `deferred_closure_requirements`.
We now manually apply the final closure requirements to each body after handling opaque types.
This works, except that we may need the region constraints of nested bodies to successfully define an opaque type in the parent. This is handled by using a new `fn compute_closure_requirements_modulo_opaques` which duplicates region checking - while ignoring any errors - before we've added the constraints from `apply_computed_concrete_opaque_types`. This is necessary for a lot of async tests, as pretty much the entire function is inside of an async block while the opaque type gets defined in the parent.
As an performance optimization we only use `fn compute_closure_requirements_modulo_opaques` in case the nested body actually depends on any opaque types. Otherwise we eagerly call `borrowck_check_region_constraints` and apply the final closure region requirements right away.
## Impact on stable code
Handling the opaque type uses in the parent function now only uses the closure requirements *modulo opaques*, while it previously also considered member constraints from nested bodies. `External` regions are never valid choice regions. Also, member constraints will never constrain a member region if it is required to be outlived by an external region, as that fails the upper-bound check. 564ee21912/compiler/rustc_borrowck/src/region_infer/opaque_types/member_constraints.rs (L90-L96)
Member constraints therefore never add constraints for external regions :>
r? `@BoxyUwU`
pub async fn impl is monomorphized when func itself is monomorphized
Implentation coroutine (`func::{closure#0}`) is monomorphized, when func itself is monomorphized.
Currently, when `pub async fn foo(..)` is exported from lib and used in several dependent crates, only 'header' function is monomorphized in the defining crate. 'header' function, returning coroutine object, is monomorphized, but the coroutine's poll function (which actually implements all the logic for the function) is not. In such situation, `func::{closure#0}` will be monomorphized in every dependency.
This PR adds monomorphization for `func::{closure#0}` (coroutine poll function), when func itself is monomorphized.
Simple test with one lib async function and ten dependent crates (executable) that use the function, shows 5-7% compilation time improvement (single-threaded).
Rollup of 5 pull requests
Successful merges:
- rust-lang/rust#145468 (dedup recip, powi, to_degrees, and to_radians float tests)
- rust-lang/rust#145643 (coverage: Build an "expansion tree" and use it to unexpand raw spans)
- rust-lang/rust#145754 (fix(lexer): Don't require frontmatters to be escaped with indented fences)
- rust-lang/rust#146060 (fixup nix dev shell again)
- rust-lang/rust#146068 (compiletest: Capture panic messages via a custom panic hook)
r? `@ghost`
`@rustbot` modify labels: rollup
fix(lexer): Don't require frontmatters to be escaped with indented fences
The RFC only limits hyphens at the beginning of lines and not if they are indented or embedded in other content.
Sticking to that approach was confirmed by the T-lang liason at https://github.com/rust-lang/rust/issues/141367#issuecomment-3202217544
There is a regression in error message quality which I'm leaving for someone if they feel this needs improving.
Tracking issue: rust-lang/rust#136889Fixesrust-lang/rust#141367
Suggest method name with maybe ty mismatch
Fixesrust-lang/rust#146008
I think it's ok to suggest method name even when the return ty mismatch, since we only reporting in `Applicability::MaybeIncorrect`, user may add `()` and continue to fix following errors.
r? ```@estebank```
Detect negative literal inferred to unsigned integer
```
error[E0277]: the trait bound `usize: Neg` is not satisfied
--> $DIR/negative-literal-infered-to-unsigned.rs:2:14
|
LL | for x in -5..5 {
| ^^ the trait `Neg` is not implemented for `usize`
|
help: consider specifying an integer type that can be negative
|
LL | for x in -5isize..5 {
| +++++
```
Applying this suggestion will always end up in another E0308 error at the point where the unsigned inference comes from, which should help with understanding what the actual problem is.
Fixrust-lang/rust#83413.
Fix format string grammar in docs and improve alignment error message for #144023
This PR improves error messages and documentation for format strings involving alignment and formatting traits.
Highlights:
- Clearer error messages for invalid alignment specifiers (e.g., `{0:#X>18}`), showing the expected `<`, `^`, or `>` and a working example:
println!("{0:>#18X}", value);
- Updated UI test `format-alignment-hash.rs` to reflect the improved error output.
- Documentation clarification: ensures examples correctly show how width, alignment, and traits like `x`, `X`, `#` combine.
Motivation:
Previously, using `#` with alignment and width produced confusing errors. This PR guides users on the correct syntax and provides actionable examples.
Testing:
- Built the compiler (`./x build`)
- Blessed and ran UI tests (`./x. test src/test/ui/fmt/format-alignment-hash.rs --bless`)
- Verified full test suite passes (`./x test`)
Issue: rust-lang/rust#144023
Detect missing `if let` or `let-else`
During `let` binding parse error and encountering a block, detect if there is a likely missing `if` or `else`:
```
error: expected one of `.`, `;`, `?`, `else`, or an operator, found `{`
--> $DIR/missing-if-let-or-let-else.rs:14:25
|
LL | let Some(x) = foo() {
| ^ expected one of `.`, `;`, `?`, `else`, or an operator
|
help: you might have meant to use `if let`
|
LL | if let Some(x) = foo() {
| ++
help: alternatively, you might have meant to use `let else`
|
LL | let Some(x) = foo() else {
| ++++
```
Fixrust-lang/rust#107806.
```
error[E0277]: the trait bound `usize: Neg` is not satisfied
--> $DIR/negative-literal-infered-to-unsigned.rs:2:14
|
LL | for x in -5..5 {
| ^^ the trait `Neg` is not implemented for `usize`
|
help: consider specifying an integer type that can be negative
|
LL | for x in -5isize..5 {
| +++++
```
```
error: unused variable: `Batery`
--> $DIR/binding-typo-2.rs:110:9
|
LL | Batery => {}
| ^^^^^^
|
help: if this is intentional, prefix it with an underscore
|
LL | _Batery => {}
| +
help: you might have meant to pattern match on the similarly named constant `Battery`
|
LL | Battery => {}
| +
```
When encountering a typo in a pattern that gets interpreted as an unused binding, look for unit struct/variant of the same type as the binding:
```
error: unused variable: `Non`
--> $DIR/binding-typo-2.rs:36:9
|
LL | Non => {}
| ^^^
|
help: if this is intentional, prefix it with an underscore
|
LL | _Non => {}
| +
help: you might have meant to pattern match on the similarly named variant `None`
|
LL - Non => {}
LL + std::prelude::v1::None => {}
|
```
Add managarm as a tier 3 target
This PR aims to introduce the `x86_64-unknown-managarm-mlibc` as a tier 3 target to Rust.
[managarm](https://github.com/managarm/managarm) is a microkernel with fully asynchronous I/O that also provides a POSIX server. Despite the differences, managarm provides good compatability with POSIX and Linux APIs. As a rule of thumb, barring OS-specific code, it should be mostly source-compatible with Linux.
We have been shipping a patched rust for over 25 releases now, and we would like to upstream our work. For a smoother process, this PR only adds the target to rustc and some documentation. `std` support will be added in a future PR.
## Addressing the tier 3 target 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.)
`@no92,` `@64` and `@Dennisbonke` will be target maintainers.
> 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.
`x86_64-unknown-managarm-mlibc` is what we use for LLVM as well.
> 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 be subject 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.
[managarm](https://github.com/managarm/managarm) is licensed as MIT. No dependencies were added.
> 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. None of the listed maintainers are on a Rust team.
> 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.
Support for `std` will be provided in a future PR. Only minor changes are required, however they depend on support in the `libc` crate which will be PRed in soon.
> 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.
The steps needed to take are described in the documentation provided with this PR.
> 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.
We have no indication that anything breaks due to this PR.
> Tier 3 targets must be able to produce assembly using at least one of rustc's supported backends from any host target.
No problems here, as we target `x86_64`.
r? compiler-team
When encountering an or-pattern with a binding not available in all patterns, look for consts and unit struct/variants that have similar names as the binding to detect typos.
```
error[E0408]: variable `Ban` is not bound in all patterns
--> $DIR/binding-typo.rs:22:9
|
LL | (Foo, _) | (Ban, Foo) => {}
| ^^^^^^^^ --- variable not in all patterns
| |
| pattern doesn't bind `Ban`
|
help: you might have meant to use the similarly named unit variant `Bar`
|
LL - (Foo, _) | (Ban, Foo) => {}
LL + (Foo, _) | (Bar, Foo) => {}
|
```
For items that are not in the immedate scope, suggest the full path for them:
```
error[E0408]: variable `Non` is not bound in all patterns
--> $DIR/binding-typo-2.rs:51:16
|
LL | (Non | Some(_))=> {}
| --- ^^^^^^^ pattern doesn't bind `Non`
| |
| variable not in all patterns
|
help: you might have meant to use the similarly named unit variant `None`
|
LL - (Non | Some(_))=> {}
LL + (core::option::Option::None | Some(_))=> {}
|
```
compiler: Include span of too huge enum with `-Cdebuginfo=2`
We have the ui test `tests/ui/limits/huge-enum.rs` to ensure we emit an error if we encounter too big enums. Before this fix, compiling the test with `-Cdebuginfo=2` would not include the span of the instantiation site, because the error is then emitted from a different code path that does not include the span.
Propagate the span to the error also in the debuginfo case, so the test passes regardless of debuginfo level. I'm sure we can propagate spans in more places, but let's start small.
## Test failure without the fix
Here is what the failure looks like if you run the test without the fix:
```
[ui] tests/ui/limits/huge-enum.rs#full-debuginfo ... F
.
failures:
---- [ui] tests/ui/limits/huge-enum.rs#full-debuginfo stdout ----
Saved the actual stderr to `/home/martin/src/rust/build/x86_64-unknown-linux-gnu/test/ui/limits/huge-enum.full-debuginfo/huge-enum.full-debuginfo.stderr`
diff of stderr:
1 error: values of the type `Option<TYPE>` are too big for the target architecture
- --> $DIR/huge-enum.rs:17:9
- |
- LL | let big: BIG = None;
- | ^^^
6
7 error: aborting due to 1 previous error
8
The actual stderr differed from the expected stderr
To update references, rerun the tests and pass the `--bless` flag
To only update this specific test, also pass `--test-args limits/huge-enum.rs`
```
as can be seen, the `span` used to be missing with `debuginfo=2`.
## See also
This is one small step towards resolving rust-lang/rust#61117.
cc https://github.com/rust-lang/rust/pull/144499 which began running UI tests with `rust.debuginfo-level-tests=1`. This PR is part of preparing for increasing that to debuglevel 2.
