Some tweaks to the parallel query cycle handler
This renames `deadlock` to `break_query_cycles`. The abort logic is moved next to the thread spawning and gives the thread a name.
Fixes https://github.com/rust-lang/rust/issues/122035.
r? ```@oli-obk```
Move metadata header and version checks together
This will make it easier to report rustc versions for older metadata formats.
Split out of https://github.com/rust-lang/rust/pull/120855
Eagerly translate `HelpUseLatestEdition` in parser diagnostics
Fixes#122130.
This makes me suspicious of these other two usage of `add_to_diagnostic()`. Would they *also* crash? I haven't attempted to construct test cases for them.
```
compiler/rustc_parse/src/parser/expr.rs
3453: errors::HelpUseLatestEdition::new().add_to_diagnostic(e);
compiler/rustc_hir_typeck/src/expr.rs
2603: HelpUseLatestEdition::new().add_to_diagnostic(&mut err);
```
This also seems like a footgun?
Misc improvements to non local defs lint implementation
This PR is a collection of small improvements I found when I [needlessly tried](https://www.github.com/rust-lang/rust/pull/120393#issuecomment-1971787475) to fix a "perf-regression" in the lint implementation.
I recommend looking at each commit individually.
Using `Ord` to accomplish a meaning of subset relationship
can be hard to read. The existing uses for that are easily
replaced with a `match`, and in my opinion, more readable
without needing to resorting to comments to explain the
intention.
Optimize `Symbol::integer` by utilizing in-place formatting
This PR optimize `Symbol::integer` by utilizing `itoa` in-place formatting instead of going through a dynamically allocated `String` and the format machinery.
<details>
For some context: I was profiling `rustc --check-cfg` with callgrind and due to the way we currently setup all the targets and we end-up calling `Symbol::integer` multiple times for all the targets. Using `itoa` reduced the number of instructions.
</details>
Lint singleton gaps after exclusive ranges
In the discussion to stabilize exclusive range patterns (https://github.com/rust-lang/rust/issues/37854), it has often come up that they're likely to cause off-by-one mistakes. We already have the `overlapping_range_endpoints` lint, so I [proposed](https://github.com/rust-lang/rust/issues/37854#issuecomment-1845580712) a lint to catch the complementary mistake.
This PR adds a new `non_contiguous_range_endpoints` lint that catches likely off-by-one errors with exclusive range patterns. Here's the idea (see the test file for more examples):
```rust
match x {
0..10 => ..., // WARN: this range doesn't match `10_u8` because `..` is an exclusive range
11..20 => ..., // this could appear to continue range `0_u8..10_u8`, but `10_u8` isn't matched by either of them
_ => ...,
}
// help: use an inclusive range instead: `0_u8..=10_u8`
```
More precisely: for any exclusive range `lo..hi`, if `hi+1` is matched by another range but `hi` isn't, we suggest writing an inclusive range `lo..=hi` instead. We also catch `lo..T::MAX`.
Avoid invoking the `intrinsic` query for DefKinds other than `Fn` or `AssocFn`
fixes the perf regression from https://github.com/rust-lang/rust/pull/120675 by only invoking (and thus inserting into the dep graph) the `intrinsic` query if the `DefKind` matches items that can actually be intrinsics
Subtree sync for rustc_codegen_cranelift
The main highlight this time is a bunch of new vendor intrinsics. Cranelift has also been updated to 0.105. And there were a bunch of big-endian fixes.
r? `@ghost`
`@rustbot` label +A-codegen +A-cranelift +T-compiler
Don't ICE if we collect no RPITITs unless there are no unification errors
Move an assertion in `collect_return_position_impl_trait_in_trait_tys` to after the `ObligationCtxt::eq` calls, so that we only assert and ICE if we have unification errors.
Fixes#121468
Fix misaligned loads when loading UEFI arg pointers
Currently, the two UEFI argument pointers are stored in an `alloca` of alignment 1, a pointer to which is then passed as `argv`. However, [the library code](9c3ad802d9/library/std/src/sys/pal/uefi/mod.rs (L60-L61)) treats `argv` as a pointer to an array of pointers and dereferences it as such, meaning that it presumes the `alloca` is aligned to at least the alignment of a pointer. This PR fixes this mismatch by aligning the `alloca` to the alignment of a pointer.
This PR also changed the `gep` to use the new `inbounds_ptradd` method.
Add the new description field to Target::to_json, and add descriptions for some MSVC targets
The original PR to add a `description` field to `Target` (<https://github.com/rust-lang/rust/pull/121905>) didn't add the field to `Target::to_json`, which meant that the `check_consistency` testwould fail if you tried to set a description as it wouldn't survive round-tripping via JSON: https://github.com/rust-lang/rust/actions/runs/8180997936/job/22370052535#step:27:4967
This change adds the field to `Target::to_json`, and sets some descriptions to verify that it works correctly.
Tweak the way we protect in-place function arguments in interpreters
Use `MPlaceTy` instead of `PlaceTy` in `FnArg` and ignore (copy) locals in an earlier step ("Locals that don't have their address taken are as protected as they can ever be").
This seems to be crucial for tail call support (as they can't refer to caller's locals which are killed when replacing the stack frame).
r? `@RalfJung`
cc `@oli-obk`
see https://github.com/rust-lang/rust/pull/121273#issuecomment-1980210690
Merge `collect_mod_item_types` query into `check_well_formed`
follow-up to https://github.com/rust-lang/rust/pull/121154
this removes more potential parallel-compiler bottlenecks and moves diagnostics for the same items next to each other, instead of grouping diagnostics by analysis kind
Use `MPlaceTy` instead of `PlaceTy` in `FnArg` and ignore (copy) locals in an
earlier step ("Locals that don't have their address taken are as protected as
they can ever be").
This seems to be crucial for tail call support (as they can't refer to caller's
locals which are killed when replacing the stack frame).
Use `ControlFlow` in visitors.
Follow up to #121256
This does have a few small behaviour changes in some diagnostic output where the visitor will now find the first match rather than the last match. The change in `find_anon_types.rs` has the only affected test. I don't see this being an issue as the last occurrence isn't any better of a choice than the first.
Refactor pre-getopts command line argument handling
Rebased version of #111658. I've also fixed the Windows CI failure (although I don't have access to Windows to test it myself).
Make TAITs and ATPITs capture late-bound lifetimes in scope
This generalizes the behavior that RPITs have, where they duplicate their in-scope lifetimes so that they will always *reify* late-bound lifetimes that they capture. This allows TAITs and ATPITs to properly error when they capture in-scope late-bound lifetimes.
r? `@oli-obk` cc `@aliemjay`
Fixes#122093 and therefore https://github.com/rust-lang/rust/pull/120700#issuecomment-1981213868
Add asm goto support to `asm!`
Tracking issue: #119364
This PR implements asm-goto support, using the syntax described in "future possibilities" section of [RFC2873](https://rust-lang.github.io/rfcs/2873-inline-asm.html#asm-goto).
Currently I have only implemented the `label` part, not the `fallthrough` part (i.e. fallthrough is implicit). This doesn't reduce the expressive though, since you can use label-break to get arbitrary control flow or simply set a value and rely on jump threading optimisation to get the desired control flow. I can add that later if deemed necessary.
r? ``@Amanieu``
cc ``@ojeda``
Add arm64ec-pc-windows-msvc target
Introduces the `arm64ec-pc-windows-msvc` target for building Arm64EC ("Emulation Compatible") binaries for Windows.
For more information about Arm64EC see <https://learn.microsoft.com/en-us/windows/arm/arm64ec>.
## 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 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.
Target uses the `arm64ec` architecture to match LLVM and MSVC, and the `-pc-windows-msvc` suffix to indicate that it targets Windows via the MSVC environment.
> 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.
Target name exactly specifies the type of code that will be produced.
> If possible, use only letters, numbers, dashes and underscores for the name. Periods (.) are known to cause issues in Cargo.
Done.
> 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.
Uses the same dependencies, requirements and licensing as the other `*-pc-windows-msvc` targets.
> Anything added to the Rust repository must be under the standard Rust license (MIT OR Apache-2.0).
Understood.
> 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.
Uses the same dependencies, requirements and licensing as the other `*-pc-windows-msvc` targets.
> 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, I am not a member of the 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.
Both `core` and `alloc` are supported.
Support for `std` depends on making changes to the standard library, `stdarch` and `backtrace` which cannot be done yet as they require fixes coming in LLVM 18.
> The target must provide documentation for the Rust community explaining how to build for the target, using cross-compilation if possible. If the target supports running binaries, or running tests (even if they do not pass), the documentation must explain how to run such binaries or tests for the target, using emulation if possible or dedicated hardware if necessary.
Documentation is provided in src/doc/rustc/src/platform-support/arm64ec-pc-windows-msvc.md
> Tier 3 targets must not impose burden on the authors of pull requests, or other developers in the community, to maintain the target. In particular, do not post comments (automated or manual) on a PR that derail or suggest a block on the PR based on a tier 3 target. Do not send automated messages or notifications (via any medium, including via `@)` to a PR author or others involved with a PR regarding a tier 3 target, unless they have opted into such messages.
> Backlinks such as those generated by the issue/PR tracker when linking to an issue or PR are not considered a violation of this policy, within reason. However, such messages (even on a separate repository) must not generate notifications to anyone involved with a PR who has not requested such notifications.
> Patches adding or updating tier 3 targets must not break any existing tier 2 or tier 1 target, and must not knowingly break another tier 3 target without approval of either the compiler team or the maintainers of the other tier 3 target.
> In particular, this may come up when working on closely related targets, such as variations of the same architecture with different features. Avoid introducing unconditional uses of features that another variation of the target may not have; use conditional compilation or runtime detection, as appropriate, to let each target run code supported by that target.
Understood.
Don't pass a break scope to `Builder::break_for_else`
This method would previously take a target scope, and then verify that it was equal to the scope on top of the if-then scope stack.
In practice, this means that callers have to go out of their way to pass around redundant scope information that's already on the if-then stack.
So it's easier to just retrieve the correct scope directly from the if-then stack, and simplify the other code that was passing it around.
---
Both ways of indicating the break target were introduced in #88572. I haven't been able to find any strong indication of whether this was done deliberately, or whether it was just an implementation artifact. But to me it doesn't seem useful to carefully pass around the same scope in two different ways.
AST validation: Improve handling of inherent impls nested within functions and anon consts
Minimal fix for issue #121607 extracted from PR #120698 for ease of backporting and since I'd like to improve PR #120698 in such a way that it makes AST validator truly robust against such sort of regressions (AST validator is generally *beyond* footgun-y atm). The current version of PR #120698 sort of does that already but there's still room for improvement.
Fixes#89342.
Fixes [after beta-backport] #121607.
Partially addresses #119924 (#120698 aims to fully fix it).
---
### Explainer
The last commit of PR #119505 regressed issue #121607.
Previously we would reject visibilities on associated items with `visibility_not_permitted` if we were in a trait (by checking the parameter `ctxt` of `visit_assoc_item` which was 100% accurate) or if we were in a trait impl (by checking a flag called `in_trait_impl` tracked in `AstValidator` which was/is only accurate if the visitor methods correctly updated it which isn't actually the case giving rise to the old open issue #89342).
In PR #119505, I moved even more state into the `AstValidator` by generalizing the flag `in_trait_impl` to `trait_or_trait_impl` to be able to report more precise diagnostics (modeling *Trait | TraitImpl*). However since we/I didn't update `trait_or_trait_impl` in all places to reflect reality (similar to us not updating `in_trait_impl` before), this lead to https://github.com/rust-lang/rust/issues/121607#issuecomment-1963084636 getting wrongfully rejected. Since PR #119505 we reject visibilities if the “globally tracked” (wrt. to `AstValidator`) `outer_trait_or_trait_impl` is `Some`.
Crucially, when visiting an inherent impl, I never reset `outer_trait_or_trait_impl` back to `None` leading us to believe that `bar` in the stack [`trait Foo` > `fn foo` > `impl Bar` > `pub fn bar`] (from the MCVE) was an inherent associated item (we saw `trait Foo` but not `impl Bar` before it).
The old open issue #89342 is caused by the aforementioned issue of us never updating `in_trait_impl` prior to my PR #119505 / `outer_trait_or_trait` after my PR. Stack: [`impl Default for Foo` > `{` > `impl Foo` > `pub const X`] (we only saw `impl Default for Foo` but not the `impl Foo` before it).
---
This PR is only meant to be a *hot fix*. I plan on completely *rewriting* `AstValidator` from the ground up to not rely on “globally tracked” state like this or at least make it close to impossible to forget updating it when descending into nested items (etc.). Other visitors do a way better job at that (e.g. AST lowering). I actually plan on experimenting with moving more and more logic from `AstValidator` into the AST lowering pass/stage/visitor to follow the [Parse, don't validate](https://lexi-lambda.github.io/blog/2019/11/05/parse-don-t-validate/) “pattern”.
---
r? `@compiler-errors`
Remove `feed_local_def_id`
best reviewed commit by commit
Basically I returned `TyCtxtFeed` from `create_def` and then preserved that in the local caches
based on https://github.com/rust-lang/rust/pull/121084
r? ````@petrochenkov````
Stabilize the `#[diagnostic]` namespace and `#[diagnostic::on_unimplemented]` attribute
This PR stabilizes the `#[diagnostic]` attribute namespace and a minimal option of the `#[diagnostic::on_unimplemented]` attribute.
The `#[diagnostic]` attribute namespace is meant to provide a home for attributes that allow users to influence error messages emitted by the compiler. The compiler is not guaranteed to use any of this hints, however it should accept any (non-)existing attribute in this namespace and potentially emit lint-warnings for unused attributes and options. This is meant to allow discarding certain attributes/options in the future to allow fundamental changes to the compiler without the need to keep then non-meaningful options working.
The `#[diagnostic::on_unimplemented]` attribute is allowed to appear on a trait definition. This allows crate authors to hint the compiler to emit a specific error message if a certain trait is not implemented. For the `#[diagnostic::on_unimplemented]` attribute the following options are implemented:
* `message` which provides the text for the top level error message
* `label` which provides the text for the label shown inline in the broken code in the error message
* `note` which provides additional notes.
The `note` option can appear several times, which results in several note messages being emitted. If any of the other options appears several times the first occurrence of the relevant option specifies the actually used value. Any other occurrence generates an lint warning. For any other non-existing option a lint-warning is generated.
All three options accept a text as argument. This text is allowed to contain format parameters referring to generic argument or `Self` by name via the `{Self}` or `{NameOfGenericArgument}` syntax. For any non-existing argument a lint warning is generated.
This allows to have a trait definition like:
```rust
#[diagnostic::on_unimplemented(
message = "My Message for `ImportantTrait<{A}>` is not implemented for `{Self}`",
label = "My Label",
note = "Note 1",
note = "Note 2"
)]
trait ImportantTrait<A> {}
```
which then generates for the following code
```rust
fn use_my_trait(_: impl ImportantTrait<i32>) {}
fn main() {
use_my_trait(String::new());
}
```
this error message:
```
error[E0277]: My Message for `ImportantTrait<i32>` is not implemented for `String`
--> src/main.rs:14:18
|
14 | use_my_trait(String::new());
| ------------ ^^^^^^^^^^^^^ My Label
| |
| required by a bound introduced by this call
|
= help: the trait `ImportantTrait<i32>` is not implemented for `String`
= note: Note 1
= note: Note 2
```
[Playground with the unstable feature](https://play.rust-lang.org/?version=nightly&mode=debug&edition=2021&gist=05133acce8e1d163d481e97631f17536)
Fixes#111996
Rollup of 10 pull requests
Successful merges:
- #121863 (silence mismatched types errors for implied projections)
- #122043 (Apply `EarlyBinder` only to `TraitRef` in `ImplTraitHeader`)
- #122066 (Add proper cfgs for struct HirIdValidator used only with debug-assert)
- #122104 (Rust is a proper name: rust → Rust)
- #122110 (Make `x t miri` respect `MIRI_TEMP`)
- #122114 (Make not finding core a fatal error)
- #122115 (Cancel parsing ever made during recovery)
- #122123 (Don't require specifying unrelated assoc types when trait alias is in `dyn` type)
- #122126 (Fix `tidy --bless` on ̶X̶e̶n̶i̶x̶ Windows)
- #122129 (Set `RustcDocs` to only run on host)
r? `@ghost`
`@rustbot` modify labels: rollup
Don't require specifying unrelated assoc types when trait alias is in `dyn` type
Object types must specify the associated types for all of the principal trait ref's supertraits. However, we weren't doing elaboration properly, so we incorrectly errored with erroneous suggestions to specify associated types that were unrelated to that principal trait ref. To fix this, use proper supertrait elaboration when expanding trait aliases in `conv_object_ty_poly_trait_ref`.
**NOTE**: Please use the ignore-whitespace option when reviewing. This only touches a handful of lines.
r? oli-obk or please feel free to reassign.
Fixes#122118
Make not finding core a fatal error
Similar to https://github.com/rust-lang/rust/pull/120472, this prevents terminal spam. In particular, it makes the good diagnostic visible when you try to use a target that's not installed.
Apply `EarlyBinder` only to `TraitRef` in `ImplTraitHeader`
Resolves#121852
This PR
1. Moves `EarlyBinder` to `TraitRef` inside `ImplTraitHeader`,
2. Changes visibility of `coherence::builtin::check_trait` to `pub(super)` from `pub` as it seems not being re-exported from the `coherence` module.
silence mismatched types errors for implied projections
Currently, if a trait bound is not satisfied, then we suppress any errors for the trait's supertraits not being satisfied, but still report errors for super projections not being satisfied.
For example:
```rust
trait Super {
type Assoc;
}
trait Sub: Super<Assoc = ()> {}
```
Before this PR, if `T: Sub` is not satisfied, then errors for `T: Super` are suppressed, but errors for `<T as Super>::Assoc == ()` are still shown. This PR makes it so that errors about super projections not being satisfied are also suppressed.
The errors are only suppressed if the span of the trait obligation matches the span of the super predicate obligation to avoid silencing error that are not related. This PR removes some differences between the spans of supertraits and super projections to make the suppression work correctly.
This PR fixes the majority of the diagnostics fallout when making `Thin` a supertrait of `Sized` (in a future PR).
cc https://github.com/rust-lang/rust/pull/120354#issuecomment-1930585382
cc `@lcnr`
interpret: avoid a long-lived PlaceTy in stack frames
`PlaceTy` uses a representation that's not very stable under changes to the stack. I'd feel better if we didn't have one in the long-term machine state.
r? `@oli-obk`
This method would previously take a target scope, and then verify that it
was equal to the scope on top of the if-then scope stack.
In practice, this means that callers have to go out of their way to pass around
redundant scope information that's already on the if-then stack.
So it's easier to just retrieve the correct scope directly from the if-then
stack, and simplify the other code that was passing it around.
Rollup of 9 pull requests
Successful merges:
- #121958 (Fix redundant import errors for preload extern crate)
- #121976 (Add an option to have an external download/bootstrap cache)
- #122022 (loongarch: add frecipe and relax target feature)
- #122026 (Do not try to format removed files)
- #122027 (Uplift some feeding out of `associated_type_for_impl_trait_in_impl` and into queries)
- #122063 (Make the lowering of `thir::ExprKind::If` easier to follow)
- #122074 (Add missing PartialOrd trait implementation doc for array)
- #122082 (remove outdated fixme comment)
- #122091 (Note why we're using a new thread in `test_get_os_named_thread`)
r? `@ghost`
`@rustbot` modify labels: rollup
Introduces the `arm64ec-pc-windows-msvc` target for building Arm64EC ("Emulation Compatible") binaries for Windows.
For more information about Arm64EC see <https://learn.microsoft.com/en-us/windows/arm/arm64ec>.
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 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.
Target uses the `arm64ec` architecture to match LLVM and MSVC, and the `-pc-windows-msvc` suffix to indicate that it targets Windows via the MSVC environment.
> 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.
Target name exactly specifies the type of code that will be produced.
> If possible, use only letters, numbers, dashes and underscores for the name. Periods (.) are known to cause issues in Cargo.
Done.
> 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.
Uses the same dependencies, requirements and licensing as the other `*-pc-windows-msvc` targets.
> Anything added to the Rust repository must be under the standard Rust license (MIT OR Apache-2.0).
Understood.
> 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.
Uses the same dependencies, requirements and licensing as the other `*-pc-windows-msvc` targets.
> 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, I am not a member of the 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.
Both `core` and `alloc` are supported.
Support for `std` dependends on making changes to the standard library, `stdarch` and `backtrace` which cannot be done yet as the bootstrapping compiler raises a warning ("unexpected `cfg` condition value") for `target_arch = "arm64ec"`.
> The target must provide documentation for the Rust community explaining how to build for the target, using cross-compilation if possible. If the target supports running binaries, or running tests (even if they do not pass), the documentation must explain how to run such binaries or tests for the target, using emulation if possible or dedicated hardware if necessary.
Documentation is provided in src/doc/rustc/src/platform-support/arm64ec-pc-windows-msvc.md
> Tier 3 targets must not impose burden on the authors of pull requests, or other developers in the community, to maintain the target. In particular, do not post comments (automated or manual) on a PR that derail or suggest a block on the PR based on a tier 3 target. Do not send automated messages or notifications (via any medium, including via @) to a PR author or others involved with a PR regarding a tier 3 target, unless they have opted into such messages.
> Backlinks such as those generated by the issue/PR tracker when linking to an issue or PR are not considered a violation of this policy, within reason. However, such messages (even on a separate repository) must not generate notifications to anyone involved with a PR who has not requested such notifications.
> Patches adding or updating tier 3 targets must not break any existing tier 2 or tier 1 target, and must not knowingly break another tier 3 target without approval of either the compiler team or the maintainers of the other tier 3 target.
> In particular, this may come up when working on closely related targets, such as variations of the same architecture with different features. Avoid introducing unconditional uses of features that another variation of the target may not have; use conditional compilation or runtime detection, as appropriate, to let each target run code supported by that target.
Understood.
Explicitly assign constructed C++ classes
C++ style guides I am aware of recommend specifically preferring = syntax for any classes with fairly obvious constructors[^0] that do not perform any complicated logic in their constructor. I contend that all constructors that the `rustc_llvm` code uses qualify. This has only become more common since C++ 17 guaranteed many cases of copy initialization elision.
The other detail is that I tried to ask another contributor with infinitely more C++ experience than me (i.e. any) what this constructor syntax was, and they thought it was a macro. I know of no other language that has adopted this same syntax. As the rustc codebase features many contributors experienced in many other languages, using a less... unique... style has many other benefits in making this code more lucid and maintainable, which is something it direly needs.
[^0]: e.g. https://abseil.io/tips/88
Add better explanation for `rustc_index::IndexVec`
I feel like I didn't do a great job explaining what this does in https://github.com/rust-lang/rust/pull/119800, so this PR tries to give an example of why and how you would use it.
Addresses #93792.
remove outdated fixme comment
The `TraitPredicate` no longer has constness as we have desugared it to work with the type system through const generics instead.
Make the lowering of `thir::ExprKind::If` easier to follow
This targets a few code patterns that I found very confusing when I first tried to understand what this code is doing.
No functional changes. I recommend looking at the changes individually, with whitespace hidden.
Uplift some feeding out of `associated_type_for_impl_trait_in_impl` and into queries
This PR moves the `type_of` and `generics_of` query feeding out of `associated_type_for_impl_trait_in_impl`, since eagerly feeding results in query cycles due to a subtle interaction with `resolve_bound_vars`.
Fixes#122019
r? spastorino
loongarch: add frecipe and relax target feature
This PR adds `frecipe` and `relax` target features to LoongArch:
* frecipe - Support frecipe.{s/d} and frsqrte.{s/d} instructions..
* relax - Enable Linker relaxation.
cleanup: remove zero-offset GEP
This GEP would've been used to change the pointer type in the past, but after opaque pointers it's a no-op. I missed removing this in #105545.
Split out from #121577.
Fix linting paths with qself in `unused_qualifications`
Fixes#121999
`resolve_qpath` ends up being called again with `qself` set to `None` to check trait items from fully qualified paths. To avoid this the lint is moved to a place that accounts for this already
96561a8fd1/compiler/rustc_resolve/src/late.rs (L4074-L4088)
r? `````@petrochenkov`````
Removing absolute path in proc-macro
With rust 1.75 the absolute build path name is embedding into proc-macro (.rustc section) and which causes reproducibility issues.
Detailed issue description is here - https://github.com/rust-lang/rust/issues/120825#issuecomment-1964307219
With this change the 'absolute path' changed back to '/rust/$hash' format as in earlier revisions.
Rework `untranslatable_diagnostic` lint
Currently it only checks calls to functions marked with `#[rustc_lint_diagnostics]`. This PR changes it to check calls to any function with an `impl Into<{D,Subd}iagnosticMessage>` parameter. This greatly improves its coverage and doesn't rely on people remembering to add `#[rustc_lint_diagnostics]`. It also lets us add `#[rustc_lint_diagnostics]` to a number of functions that don't have an `impl Into<{D,Subd}iagnosticMessage>`, such as `Diag::span`.
r? ``@davidtwco``
avoid overlapping privacy suggestion for single nested imports
Fixes#114884
This PR aims to avoid confusion inside braces for import suggestions.
r? ``@petrochenkov``
Change the documented implicit value of `-C instrument-coverage` to `=yes`
The option-value parser for `-Cinstrument-coverage=` currently accepts the following stable values:
- `all` (implicit value of plain `-Cinstrument-coverage`)
- `yes`, `y`, `on`, `true` (undocumented aliases for `all`)
- `off` (default; same as not specifying `-Cinstrument-coverage`)
- `no`, `n`, `false`, `0` (undocumented aliases for `off`)
I'd like to rearrange and re-document the stable values as follows:
- `no` (default; same as not specifying `-Cinstrument-coverage`)
- `n`, `off`, `false` (documented aliases for `no`)
- `0` (undocumented alias for `no`)
- `yes` (implicit value of plain `-Cinstrument-coverage`)
- `y`, `on`, `true` (documented aliases for `yes`)
- `all` (documented as *currently* an alias for `yes` that may change; discouraged but not deprecated)
The main changes being:
- Documented default value changes from `off` to `no`
- Documented implicit value changes from `all` to `yes`
- Other boolean aliases (`n`, `off`, `false`, `y`, `on`, `true`) are explicitly documented
- `all` remains currently an alias for `yes`, but is explicitly documented as being able to change in the future
- `0` remains an undocumented but stable alias for `no`
- The actual behaviour of coverage instrumentation does not change
# Why?
The choice of `all` as the implicit value only really makes sense in the context of the unstable `except-unused-functions` and `except-unused-generics` values. That arrangement was fine for an unstable flag, but it's confusing for a stable flag whose only other stable value is `off`, and will only become more confusing if we eventually want to stabilize other fine-grained coverage option values.
(Currently I'm not aware of any plans to stabilize other coverage option values, but that's why I think now is a fine time to make this change, well before anyone actually has to care about it.)
For example, if we ever add support for opt-in instrumentation of things that are *not* instrumented by `-Cinstrument-coverage` by default, it will be very strange for the `all` value to not actually instrument all things that we know how to instrument.
# Compatibility impact
Because this is not a functional change, there is no immediate compatibility impact. However, changing the documented semantics of `all` opens up the possibility of future changes that could be considered retroactively breaking.
I don't think this is going to be a big deal in practice, for a few reasons:
- The exact behaviour of coverage instrumentation is allowed to change, so changing the behaviour of `all` is not a *stability-breaking* change, as long as it still exists and does something reasonable.
- `-Cinstrument-coverage` is mainly used by tools or scripts that can be easily updated if necessary. It's unusual for users to pass the flag directly, because processing the profiler output is complicated enough that tools/scripts tend to be necessary anyway.
- Most people who are using coverage are probably relying on `-Cinstrument-coverage` rather than explicitly passing `-Cinstrument-coverage=all`, so the number of users actually affected by this change is likely to be low, and plausibly zero.
This allows us to use real field names instead of tuple element numbers.
Renaming `previous_drops` to `existing_drops_map` clarifies that "previous" was
unrelated to drop order.
stricter hidden type wf-check [based on #115008]
Original work by `@aliemjay` in #115008. A huge thanks to them for originally figuring out this approach ❤️
Fixes https://github.com/rust-lang/rust/issues/114728
Fixes https://github.com/rust-lang/rust/issues/114572
Instead of adding the `WellFormed` obligations when relating opaque types, we now always emit such an obligation when defining the hidden type.
This causes nested opaque types which aren't wf to error, see the comment below for the described impact. I believe this change to be desirable as it significantly reduces complexity by removing special-cases.
It also caused an issue with RPITIT: in defaulted trait methods, we add a `Projection(synthetic_assoc, rpit_of_trait_method)` clause to the `param_env`. This clause is not added to the `ParamEnv` of the nested coroutines. This caused a normalization failure in `fn check_coroutine_obligations` with the new solver. I fixed that by using the env of the typeck root instead.
r? `@oli-obk`
Embed length of offset/position into Span tag byte
This cuts the average bytes/relative span from 3.5 to 3.2 on libcore, ultimately saving ~400kb of data.
C++ style guides I am aware of recommend specifically preferring = syntax
for any classes with fairly obvious constructors[^0] that do not perform
any complicated logic in their constructor. I contend that all constructors
that the `rustc_llvm` code uses qualify. This has only become more common
since C++ 17 guaranteed many cases of copy initialization elision.
The other detail is that I tried to ask another contributor with
infinitely more C++ experience than me (i.e. any) what this constructor
syntax was, and they thought it was a macro. I know of no other language
that has adopted this same syntax. As the rustc codebase features many
contributors experienced in many other languages, using a less...
unique... style has many other benefits in making this code more
lucid and maintainable, which is something it direly needs.
[^0]: e.g. https://abseil.io/tips/88
This makes it easier to see that the call to `in_scope` returns both the then
block and the else block. The rather confusing `unpack!` step is confined to
its own separate line.
(This patch reindents several lines, so using "ignore whitespace" is
recommended in order to focus on the actual changes.)
Prior to the previous commit, `#[rust_lint_diagnostics]` attributes
could only be used on methods with an `impl Into<{D,Subd}iagMessage>`
parameter. But there are many other nearby diagnostic methods (e.g.
`Diag::span`) that don't take such a parameter and should have the
attribute.
This commit adds the missing attribute to these `Diag` methods. This
requires adding some missing
`#[allow(rustc::diagnostic_outside_of_impl)]` markers at call sites to
these methods.
Currently it only checks calls to functions marked with
`#[rustc_lint_diagnostics]`. This commit changes it to check calls to
any function with an `impl Into<{D,Subd}iagMessage>` parameter. This
greatly improves its coverage and doesn't rely on people remembering to
add `#[rustc_lint_diagnostics]`.
The commit also adds `#[allow(rustc::untranslatable_diagnostic)`]
attributes to places that need it that are caught by the improved lint.
These places that might be easy to convert to translatable diagnostics.
Finally, it also:
- Expands and corrects some comments.
- Does some minor formatting improvements.
- Adds missing `DecorateLint` cases to
`tests/ui-fulldeps/internal-lints/diagnostics.rs`.
Rollup of 9 pull requests
Successful merges:
- #121065 (Add basic i18n guidance for `Display`)
- #121744 (Stop using Bubble in coherence and instead emulate it with an intercrate check)
- #121829 (Dummy tweaks (attempt 2))
- #121857 (Implement async closure signature deduction)
- #121894 (const_eval_select: make it safe but be careful with what we expose on stable for now)
- #122014 (Change some attributes to only_local.)
- #122016 (will_wake tests fail on Miri and that is expected)
- #122018 (only set noalias on Box with the global allocator)
- #122028 (Remove some dead code)
r? `@ghost`
`@rustbot` modify labels: rollup
This always produces zero offset, regardless of what the struct layout
is.
Originally, this may have been necessary in order to change the pointer type,
but with opaque pointers, it is no longer necessary.
Rollup of 8 pull requests
Successful merges:
- #121202 (Limit the number of names and values in check-cfg diagnostics)
- #121301 (errors: share `SilentEmitter` between rustc and rustfmt)
- #121658 (Hint user to update nightly on ICEs produced from outdated nightly)
- #121846 (only compare ambiguity item that have hard error)
- #121961 (add test for #78894#71450)
- #121975 (hir_analysis: enums return `None` in `find_field`)
- #121978 (Fix duplicated path in the "not found dylib" error)
- #121991 (Merge impl_trait_in_assoc_types_defined_by query back into `opaque_types_defined_by`)
r? `@ghost`
`@rustbot` modify labels: rollup
only set noalias on Box with the global allocator
As discovered in https://github.com/rust-lang/miri/issues/3341, `noalias` and custom allocators don't go well together.
rustc can now check whether a Box uses the global allocator. This replaces the previous ad-hoc and rather unprincipled check for a zero-sized allocator.
This is the rustc part of fixing that; Miri will also need a patch.
const_eval_select: make it safe but be careful with what we expose on stable for now
As this is all still nightly-only I think `````@rust-lang/wg-const-eval````` can do that without involving t-lang.
r? `````@oli-obk`````
Cc `````@Nilstrieb````` -- the updated version of your RFC would basically say that we can remove these comments about not making behavior differences visible in stable `const fn`
Implement async closure signature deduction
Self-explanatory from title.
Regarding the interaction between signature deduction, fulfillment, and the new trait solver: I'm not worried about implementing closure signature deduction here because:
1. async closures are unstable, and
2. I'm reasonably confident we'll need to support signature deduction in the new solver somehow (i.e. via proof trees, which seem very promising).
This is in contrast to #109338, which was closed because it generalizes signature deduction for a *stable* kind of expression (`async {}` blocks and `Future` traits), and which proliferated usage may pose a stabilization hazard for the new solver.
I'll be certain to make sure sure we revisit the closure signature deduction problem by the time that async closures are being stabilized (which isn't particularly soon) (edit: Put it into the async closure tracking issue). cc `````@lcnr`````
r? `````@oli-obk`````
Stop using Bubble in coherence and instead emulate it with an intercrate check
r? `````@compiler-errors`````
This change is kinda funny, because all I've done is reimplement `Bubble` behaviour for coherence without using `Bubble` explicitly.
Merge impl_trait_in_assoc_types_defined_by query back into `opaque_types_defined_by`
Instead, when we're collecting opaques for associated items, we choose the right collection mode depending on whether we're collecting for an associated item of a trait impl or not.
r? ```@compiler-errors```
follow up to https://github.com/rust-lang/rust/pull/121838
Fix duplicated path in the "not found dylib" error
While working on the gcc backend, I couldn't figure out why I had this error:
```
error: couldn't load codegen backend /checkout/compiler/rustc_codegen_gcc/target/release/librustc_codegen_gcc.so/checkout/compiler/rustc_codegen_gcc/target/release/librustc_codegen_gcc.so: cannot open shared object file: No such file or directory
```
As you can see, the path is duplicated for some reason. After investigating a bit more, I realized that `libloading::Error::LoadLibraryExW` starts with the path of the not found dylib, making it appear twice in our error afterward (because we do render it like this: `{path}{err}`, and since the `err` starts with the path...).
Thanks to `````@bjorn3````` for linking me to https://github.com/rust-lang/rust/pull/121392. :)
hir_analysis: enums return `None` in `find_field`
Fixes#121757.
Unnamed union fields with enums are checked for, but if `find_field` causes an ICE then the compiler won't get to that point.
Hint user to update nightly on ICEs produced from outdated nightly
This is a conservative best-effort approach to detect a potentially outdated nightly; it will fallback to the regular ICE-reporting if any of the following cases are true:
- Channel is not nightly
- Version information is not available
- Version date is not parseable as a YYYY-MM-DD or is missing
- System time is at least 36 hours ahead of the user's nightly release datetime.
- Any internal features are used.
Note that I'm not sure how to make a test for this: I tested this manually by `CFG_VER_DATE="2020-02-02" ./x build library --stage 1`, and also changing the channel detection in `rustc_driver_impl` from `Some("nightly")` to `Some("nightly" | "dev")`, and then running `rustc +stage1 test.rs -Ztreat-err-as-bug=1` with a non-existent `test.rs`.
<img width="1145" alt="Screenshot 2024-02-27 at 01 12 28" src="https://github.com/rust-lang/rust/assets/39484203/eff6af2e-4b19-4a70-af57-cd739ecf0e84">
Closes#118832.
errors: share `SilentEmitter` between rustc and rustfmt
Fixesrust-lang/rustfmt#6082.
Shares the `SilentEmitter` between rustc and rustfmt, and gives it a fallback bundle (since it can emit diagnostics in some contexts).
Limit the number of names and values in check-cfg diagnostics
The Rust for Linux [feedback](https://github.com/rust-lang/rust/issues/82450#issuecomment-1947462977) to the check-cfg Call for Testing, revealed a weakness in the check-cfg. They are unbounded and in the case RfL they have ~20k cfgs and having them printed (even once) is unbearable.
This PR limits it to 35 (28 rustc well known + `feature` + `docsrs` + 5 custom) which feels like a good middle ground for regular users (i.e. Cargo users).
When it goes over that limit print the N first with " and X more".
``@rustbot`` label +F-check-cfg
Instead, when we're collecting opaques for associated items, we choose the right collection mode depending on whether we're collecting for an associated item of a trait impl or not.
This is the short description (`64-bit MinGW (Windows 7+)`) including
the platform requirements.
The reason for doing it like this is that this PR will be quite prone to
conflicts whenever targets get added, so it should be as simple as
possible to get it merged. Future PRs which migrate targets are scoped
to groups of targets, so they will not conflict as they can just touch
these.
This moves some of the information from the rustc book into the
compiler.
It cannot be queried yet, that is future work. It is also future work to
fill out all the descriptions, which will coincide with the work of
moving over existing target docs to the new format.
From `impl Into<DiagnosticMessage>` to `impl Into<Cow<'static, str>>`.
Because these functions don't produce user-facing output and we don't
want their strings to be translated.
