Rollup of 5 pull requests
Successful merges:
- #135212 (Remove outdated information in the `unreachable_pub` lint description)
- #135225 (Explicitly build proc macro test with panic=unwind)
- #135242 (add missing provenance APIs on NonNull)
- #135247 (Add a list of symbols for stable standard library crates)
- #135269 (Remove some unnecessary `.into()` calls)
r? `@ghost`
`@rustbot` modify labels: rollup
Add a list of symbols for stable standard library crates
There are a few locations where the crate name is checked against an enumerated list of `std`, `core`, `alloc`, and `proc_macro`, or some subset thereof. In most cases when we are looking for any "standard library" crate, all four crates should be treated the same. Change this so the crates are listed in one place, and that list is used wherever a list of `std` crates is needed.
`test` could be considered relevant in some of these cases, but generally treating it separate from the others seems preferable while it is unstable.
There are also a few places that Clippy will be able to use this.
Explicitly build proc macro test with panic=unwind
Fuchsia explicitly builds rust and all rust targets with `-C panic=abort` to minimize code generation size. However, when compiling a proc-macro with this setting it can cause a warning to be emitted, which breaks `tests/ui/invalid-compile-flags/crate-type-flag.rs`. This hasn't been a problem in the past for us since we compile our proc macros on host, rather than inside Fuchsia.
This attempts to fix the issue by explicitly requiring that we're using the unwinder when compiling this test to avoid the warning being emitted.
Fixes#135223
Remove outdated information in the `unreachable_pub` lint description
As far as I understand the `unreachable_pub` lint hasn't had false-positives since it started using "effective visibilities". Let's remove that warning from the lint description.
r? `@petrochenkov`
[mir-opt] GVN some more transmute cases
We already did `Transmute`-then-`PtrToPtr`; this adds the nearly-identical `PtrToPtr`-then-`Transmute`.
It also adds `transmute(Foo(x))` → `transmute(x)`, when `Foo` is a single-field transparent type. That's useful for things like `NonNull { pointer: p }.as_ptr()`. It also detects when a `Transmute` is just an identity-for-the-value `PtrCast` between different raw pointer types, to help such things fold with other GVN passes.
Found these as I was looking at <https://github.com/rust-lang/compiler-team/issues/807>-related changes. This also removes the questionably-useful "turn a transmute into a field projection" part of instsimplify (which I added ages ago without an obvious need for it) since that would just put back the field projections that MCP807 is trying to ban.
r? mir-opt
Implement `const Destruct` in old solver
Self-explanatory. Not totally settled that this is the best structure for built-in trait impls for effect goals in the new solver, but it's almost certainly the simplest.
r? lcnr or re-roll
Add new `{x86_64,i686}-win7-windows-gnu` targets
These are in symmetry with `{x86_64,i686}-win7-windows-msvc`.
> ## Tier 3 target policy
>
> At this tier, the Rust project provides no official support for a target, so we
> place minimal requirements on the introduction of targets.
>
> A proposed new tier 3 target must be reviewed and approved by a member of the
> compiler team based on these requirements. The reviewer may choose to gauge
> broader compiler team consensus via a [Major Change Proposal (MCP)][https://forge.rust-lang.org/compiler/mcp.html].
>
> A proposed target or target-specific patch that substantially changes code
> shared with other targets (not just target-specific code) must be reviewed and
> approved by the appropriate team for that shared code before acceptance.
>
> - 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.)
This is me, `@tbu-` on github.
> - 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.
Consistent with `{x86_64,i686}-win7-windows-msvc`, see also #118150.
> - 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.
AFAICT, it's the same legal situation as the tier 1 `{x86_64,i686}-pc-windows-gnu`.
> - Neither this policy nor any decisions made regarding targets shall create any
> binding agreement or estoppel by any party. If any member of an approving
> Rust team serves as one of the maintainers of a target, or has any legal or
> employment requirement (explicit or implicit) that might affect their
> decisions regarding a target, they must recuse themselves from any approval
> decisions regarding the target's tier status, though they may otherwise
> participate in discussions.
> - This requirement does not prevent part or all of this policy from being
> cited in an explicit contract or work agreement (e.g. to implement or
> maintain support for a target). This requirement exists to ensure that a
> developer or team responsible for reviewing and approving a target does not
> face any legal threats or obligations that would prevent them from freely
> exercising their judgment in such approval, even if such judgment involves
> subjective matters or goes beyond the letter of these requirements.
Understood.
> - Tier 3 targets should attempt to implement as much of the standard libraries
> as possible and appropriate (`core` for most targets, `alloc` for targets
> that can support dynamic memory allocation, `std` for targets with an
> operating system or equivalent layer of system-provided functionality), but
> may leave some code unimplemented (either unavailable or stubbed out as
> appropriate), whether because the target makes it impossible to implement or
> challenging to implement. The authors of pull requests are not obligated to
> avoid calling any portions of the standard library on the basis of a tier 3
> target not implementing those portions.
This target supports the whole libstd surface, since it's essentially reusing all of the x86_64-pc-windows-gnu target. Understood.
> - The target must provide documentation for the Rust community explaining how
> to build for the target, using cross-compilation if possible. If the target
> supports running binaries, or running tests (even if they do not pass), the
> documentation must explain how to run such binaries or tests for the target,
> using emulation if possible or dedicated hardware if necessary.
I tried to write some documentation on that.
> - 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
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> - 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.
> - Tier 3 targets must be able to produce assembly using at least one of
> rustc's supported backends from any host target. (Having support in a fork
> of the backend is not sufficient, it must be upstream.)
Understood.
> If a tier 3 target stops meeting these requirements, or the target maintainers
> no longer have interest or time, or the target shows no signs of activity and
> has not built for some time, or removing the target would improve the quality
> of the Rust codebase, we may post a PR to remove it; any such PR will be CCed
> to the target maintainers (and potentially other people who have previously
> worked on the target), to check potential interest in improving the situation.
>
Understood.
r? compiler-team
Suggest Replacing Comma with Semicolon in Incorrect Repeat Expressions
Fixes#80173
This PR detects typos in repeat expressions like `["_", 10]` and `vec![String::new(), 10]` and suggests replacing comma with semicolon.
Also, improves code in other place by adding doc comments and making use of a helper function to check if a type implements `Clone`.
References:
1. For `vec![T; N]`: https://doc.rust-lang.org/std/macro.vec.html
2. For `[T; N]`: https://doc.rust-lang.org/std/primitive.array.html
We already did `Transmute`-then-`PtrToPtr`; this adds the nearly-identical `PtrToPtr`-then-`Transmute`.
It also adds `transmute(Foo(x))` → `transmute(x)`, when `Foo` is a single-field transparent type. That's useful for things like `NonNull { pointer: p }.as_ptr()`.
Found these as I was looking at MCP807-related changes.
There are a few locations where the crate name is checked against an
enumerated list of `std`, `core`, `alloc`, and `proc_macro`, or some
subset thereof. In most of these cases, all four crates should likely be
treated the same. Change this so the crates are listed in one place, and
that list is used wherever a list of `std` crates is needed.
`test` could be considered relevant in some of these cases, but
generally treating it separate from the others seems preferable while it
is unstable.
There are also a few places that Clippy will be able to use this.
Fuchsia explicitly builds rust and all rust targets with `-C
panic=abort` to minimize code generation size. However, when compiling a
proc-macro with this setting it can cause a warning to be emitted, which
breaks `tests/ui/invalid-compile-flags/crate-type-flag.rs`. This hasn't
been a problem in the past for us since we compile our proc macros on
host, rather than inside Fuchsia.
This attempts to fix the issue by explicitly requiring that we're using
the unwinder when compiling this test to avoid the warning being
emitted.
Fixes#135223
A couple simple borrowck cleanups
This PR has a couple simple renamings:
- it's been a long time since the mapping from `Location`s to `PointIndex`es was extracted from `RegionElements` into the `DenseLocationMap`, but only the types were renamed at the time. borrowck still refers to this map as `elements`. That's confusing, especially since sometimes we also use the mapping via `LivenessValues`, and makes more sense as `location_map` instead.
- to clarify `LocationTable` is not as general as it sounds, and is only for datalog polonius. In this branch I didn't rename the handful of `location_table` fields and params to `polonius_table`, but can do that to differentiate it even more from `location_map`. I did try it locally and it looks worthwhile, so if you'd prefer I can also push it here. (Or we could even switch these datalog types and fields to even more explicit names)
- to clarify the incomprehensible `AllFacts`, it is renamed to `PoloniusFacts`. These can be referred to as `facts` within the legacy polonius module, but as `polonius_facts` outside of it to make it clear that they're not about NLLs (nor are they about in-tree polonius but that'll be magically fixed when they're removed in the future)
r? `@matthewjasper`
Exhaustively handle expressions in patterns
We currently have this invariant in HIR that a `PatKind::Lit` or a `PatKind::Range` only contains
* `ExprKind::Lit`
* `ExprKind::UnOp(Neg, ExprKind::Lit)`
* `ExprKind::Path`
* `ExprKind::ConstBlock`
So I made `PatKind::Lit` and `PatKind::Range` stop containing `Expr`, and instead created a `PatLit` type whose `kind` enum only contains those variants.
The only place code got more complicated was in clippy, as it couldn't share as much anymore with `Expr` handling
It may be interesting on merging `ExprKind::{Path,Lit,ConstBlock}` in the future and using the same `PatLit` type (under a new name).
Then it should also be easier to eliminate any and all `UnOp(Neg, Lit) | Lit` matching that we have across the compiler. Some day we should fold the negation into the literal itself and just store it on the numeric literals
Its original naming hides the fact that it's related to datalog
polonius, and bound to be deleted in the near future.
It also conflicts with the expected name for the actual NLL location
map, and prefixing it with its use will make the differentiation
possible.
`best_blame_constraint`: Blame better constraints when the region graph has cycles from invariance or `'static`
This fixes#132749 by changing which constraint is blamed for region errors in several cases. `best_blame_constraint` had a heuristic that tried to pinpoint the constraint causing an error by filtering out any constraints where the outliving region is unified with the ultimate target region being outlived. However, it used the SCCs of the region graph to do this, which is unreliable; in particular, if the target region is `'static`, or if there are cycles from the presence of invariant types, it was skipping over the constraints it should be blaming. As is the case in that issue, this could lead to confusing diagnostics. The simplest fix seems to work decently, judging by test stderr: this makes `best_blame_constraint` no longer filter constraints by their outliving region's SCC.
There are admittedly some quirks in the test output. In many cases, subdiagnostics that depend on the particular constraint being blamed have either started or stopped being emitted. After starting at this for quite a while, I think anything too fickle about whether it outputs based on the particular constraint being blamed should instead be looking at the constraint path as a whole, similar to what's done for [the placeholder-from-predicate note](https://github.com/rust-lang/rust/compare/master...dianne:rust:better-blame-constraints-for-static#diff-3c0de6462469af483c9ecdf2c4b00cb26192218ef2d5c62a0fde75107a74caaeR506).
Very many tests involving invariant types gained a note pointing out the types' invariance, but in a few cases it was lost. A particularly illustrative example is [tests/ui/lifetimes/copy_modulo_regions.stderr](https://github.com/rust-lang/rust/compare/master...dianne:rust:better-blame-constraints-for-static?expand=1#diff-96e1f8b29789b3c4ce2f77a5e0fba248829b97ef9d1ce39e7d2b4aa57b2cf4f0); I'd argue the new constraint is a better one to blame, but it lacks the variance diagnostic information that's elsewhere in the constraint path. If desired, I can try making that note check the whole path rather than just the blamed constraint.
The subdiagnostic [`BorrowExplanation::add_object_lifetime_default_note`](https://doc.rust-lang.org/nightly/nightly-rustc/rustc_borrowck/diagnostics/explain_borrow/enum.BorrowExplanation.html#method.add_object_lifetime_default_note) depends on a `Cast` being blamed, so [a special case](364ca7f99c) was necessary to keep it from disappearing from tests specifically testing for it. However, see the FIXME comment in that commit; I think the special case should be removed once that subdiagnostic works properly, but it's nontrivial enough to warrant a separate PR. Incidentally, this removes the note from a test where it was being added erroneously: in [tests/ui/borrowck/two-phase-surprise-no-conflict.stderr](https://github.com/rust-lang/rust/compare/master...dianne:rust:better-blame-constraints-for-static?expand=1#diff-8cf085af8203677de6575a45458c9e6b03412a927df879412adec7e4f7ff5e14), the object lifetime is explicitly provided and it's not `'static`.
"Elements" are `RegionElement`s. The dense location mapping was removed
from the element containers a while ago but didn't rename its use-sites.
Most of the old naming only used the mapping, and are better named
`location_map`.
arm: add unstable soft-float target feature
This has an actual usecase as mentioned [here](https://github.com/rust-lang/rust/issues/116344#issuecomment-2575324988), and with my recent ARM float ABI changes there shouldn't be any soundness concerns any more. We will reject enabling this feature on `hf` targets, but disabling it on non-`hf` targets is entirely fine -- the target feature refers to whether softfloat emulation is used for float instructions, and is independent of the ABI which we set separately via `llvm_floatabi`.
Cc ``@workingjubilee``
Convert typeck constraints in location-sensitive polonius
In this PR, we do a big chunk of the work of localizing regular outlives constraints.
The slightly annoying thing is handling effectful statements: usually the subset graph propagates loans at a single point between regions, and liveness propagates loans between points within a single region, but some statements have effects applied on exit.
This was also a problem before, in datalog polonius terms and Niko's solution at the time, this is about: the mid-point. The idea was to duplicate all MIR locations into two physical points, and orchestrate the effects with that. Somewhat easier to do, but double the CFG.
We've always believed we didn't _need_ midpoints in principle, as we can represent changes on exit as on happening entry to the successor, but there's some difficulty in tracking the position information at sufficient granularity through outlives relation (especially since we also have bidirectional edges and time-traveling now).
Now, that is surely what we should be doing in the future. In the mean time, I infer this from the kind of statement/terminator where an outlives constraint arose. It's not particularly complicated but some explanation will help clarify the code.
Assignments (in their various forms) are the quintessential example of these crossover cases: loans that would flow into the LHS would not be visible on entry to the point but on exit -- so we'll localize these edges to the successor. Let's look at a real-world example, involving invariance for bidirectional edges:
```rust
let mut _1: HashMap<i32, &'7 i32>;
let mut _3: &'9 mut HashMap<i32, &'10 i32>;
...
/* at bb1[3]: */ _3 = &'3 mut _1;
```
Here, typeck expectedly produces 3 outlives constraints today:
1. `'3 -> '9`
2. `'7 -> '10`
3. `'10 -> '7`
And we localize them like so,
1. `'3 -> '9` flows into the LHS and becomes: `3_bb1_3 -> 9_bb1_4`
2. `'7 -> '10` flows into the LHS and becomes: `7_bb1_3 -> 10_bb1_4`
3. `'10 -> '7` flows from the LHS and becomes: `10_bb1_4 -> 7_bb1_3` (time traveling 👌)
---
r? ``@jackh726``
To keep you entertained during the holidays I also threw in a couple of small changes removing cruft in the borrow checker.
We're actually getting there. The next PR will be the last one needed to get end-to-end tests working.
Use a post-monomorphization typing env when mangling components that come from impls
When mangling associated methods of impls, we were previously using the wrong param-env. Instead of using a fully monomorphized param-env like we usually do in codegen, we were taking the post-analysis param-env, and treating it as an early binder to *re-substitute* the impl args. I've pointed out the problematic old code in an inline comment.
This would give us param-envs with possibly trivial predicates that would prevent normalization via param-env shadowing.
In the example test linked below, `tests/ui/symbol-names/normalize-in-param-env.rs`, this happens when we mangle the impl `impl<P: Point2> MyFrom<P::S> for P` with the substitution `P = Vec2`. Because the where clause of the impl is `P: Point2`, which elaborates to `[P: Point2, P: Point, <P as Point>::S projects-to <P as Point2>::S2]` and the fact that `impl Point2 for Vec2` normalizes `Vec2::S2` to `Vec2::S`, this causes a cycle.
The proper fix here is to use a fully monomorphized param-env for the case where the impl is properly substituted.
Fixes#135143
While #134081 uncovered this bug for legacy symbol mangling, it was preexisting for v0 symbol mangling. This PR fixes both. The test requires a "hack" because we strip the args of the instance we're printing for legacy symbol mangling except for drop glue, so we box a closure to ensure we generate drop glue.
r? oli-obk
Normalize each signature input/output in `typeck_with_fallback` with its own span
Applies the same hack as #106582 but to the args in typeck. Greatly improves normalization error spans from a signature.
remove unnecessary `eval_verify_bound`
This does not impact any tests. I feel like any cases where this could useful should instead be fixed by a general improvement to `eval_verify_bound` to avoid having to promote this `TypeTest` in the first place 🤔
r? types cc ``@nikomatsakis``
Avoid naming variables `str`
This renames variables named `str` to other names, to make sure `str`
always refers to a type.
It's confusing to read code where `str` (or another standard type name)
is used as an identifier. It also produces misleading syntax
highlighting.
llvm: Ignore error value that is always false
See llvm/llvm-project#121851
For LLVM 20+, this function (`renameModuleForThinLTO`) has no return value. For prior versions of LLVM, this never failed, but had a signature which allowed an error value people were handling.
`@rustbot` label: +llvm-main
r? `@nikic`
Wait a moment before approving while the llvm-main infrastructure picks it up.
This renames variables named `str` to other names, to make sure `str`
always refers to a type.
It's confusing to read code where `str` (or another standard type name)
is used as an identifier. It also produces misleading syntax
highlighting.
Avoid replacing the definition of `CURRENT_RUSTC_VERSION`
Before this PR, replace-version-placeholder hardcoded the path defining CURRENT_RUSTC_VERSION (to avoid replacing it). After a refactor moved the file defining it without changing the hardcoded path, the tool started replacing the constant itself with the version number.
To avoid this from happening in the future, this changes the definition of the constant to avoid the tool from ever matching it.
r? `@workingjubilee`
mark deprecated option as deprecated in rustc_session to remove copypasta and small refactor
This marks deprecated options as deprecated via flag in options table in rustc_session, which removes copypasted deprecation text from rustc_driver_impl.
This also adds warning for deprecated `-C ar` option, which didn't emitted any warnings before.
Makes `inline_threshold` `[UNTRACKED]`, as it do nothing.
Adds few tests.
See individual commits.
Suggest to replace tuple constructor through projection
See the code example. when `Self::Assoc` normalizes to a struct that has a tuple constructor, you cannot construct the type via `Self::Assoc(field, field)`. Instead, suggest to replace it with the correct named struct.
Fixes#120871
Don't ice on bad transmute in typeck in new solver
Old trait solver ends up getting its infcx tainted because we try to normalize the type, but the new trait solver doesn't. This means we try to compute the stalled transmute obligations, which tries to normalize a type an ICEs. Let's make this a delayed bug.
r? lcnr
Improve diagnostics for `HostEffectPredicate` in the new solver
Adds derived cause for host effect predicates. Some diagnostics regress, but that's connected to the fact that our predicate visitor doesn't play well with aliases just yet.
Add support for wasm exception handling to Emscripten target
This is a draft because we need some additional setting for the Emscripten target to select between the old exception handling and the new exception handling. I don't know how to add a setting like that, would appreciate advice from Rust folks. We could maybe choose to use the new exception handling if `Ctarget-feature=+exception-handling` is passed? I tried this but I get errors from llvm so I'm not doing it right.
See llvm/llvm-project#121851
For LLVM 20+, this function (`renameModuleForThinLTO`) has no return
value. For prior versions of LLVM, this never failed, but had a
signature which allowed an error value people were handling.
The SCCs of the region graph are not a reliable heuristic to use for blaming an interesting
constraint for diagnostics. For region errors, if the outlived region is `'static`, or the involved
types are invariant in their lifetiems, there will be cycles in the constraint graph containing both
the target region and the most interesting constraints to blame. To get better diagnostics in these
cases, this commit removes that heuristic.
`ExtraConstraintInfo` was used only for a single subdiagnostic, so this moves the logic for that
to its own function and eliminates the indirection. In order to do so cleanly, this also changes
the arguments to `BorrowExplanation::add_explanation_to_diagnostic`, which happens to simplify its
call sites.
Before this commit, replace-version-placeholder hardcoded the path
defining CURRENT_RUSTC_VERSION (to avoid replacing it). After a refactor
moved the file defining it without changing the hardcoded path, the tool
started replacing the constant itself with the version number.
To avoid this from happening in the future, this changes the definition
of the constant to avoid the tool from ever matching it.
Suppress host effect predicates if underlying trait doesn't hold
Don't report two errors for when the (`HostEffectPredicate`) `T: const Trait` isn't implemented because (`TraitPredicate`) `T: Trait` doesn't even hold.
Use `PostBorrowckAnalysis` in `check_coroutine_obligations`
This currently errors with:
```
error: concrete type differs from previous defining opaque type use
--> tests/ui/coroutine/issue-52304.rs:10:21
|
10 | pub fn example() -> impl Coroutine {
| ^^^^^^^^^^^^^^ expected `{example::{closure#0} upvar_tys=() resume_ty=() yield_ty=&'{erased} i32 return_ty=() witness={example::{closure#0}}}`, got `{example::{closure#0} upvar_tys=() resume_ty=() yield_ty=&'static i32 return_ty=() witness={example::{closure#0}}}`
|
= note: previous use here
```
This is because we end up redefining the opaque in `check_coroutine_obligations` but with the `yield_ty = &'erased i32` from hir typeck, which causes the *equality* check for opaques to fail.
The coroutine obligtions in question (when `-Znext-solver` is enabled) are:
```
Binder { value: TraitPredicate(<Opaque(DefId(0:5 ~ issue_52304[4c6d]::example::{opaque#0}), []) as std::marker::Sized>, polarity:Positive), bound_vars: [] }
Binder { value: AliasRelate(Term::Ty(Alias(Opaque, AliasTy { args: [], def_id: DefId(0:5 ~ issue_52304[4c6d]::example::{opaque#0}), .. })), Equate, Term::Ty(Coroutine(DefId(0:6 ~ issue_52304[4c6d]::example::{closure#0}), [(), (), &'{erased} i32, (), CoroutineWitness(DefId(0:6 ~ issue_52304[4c6d]::example::{closure#0}), []), ()]))), bound_vars: [] }
Binder { value: AliasRelate(Term::Ty(Coroutine(DefId(0:6 ~ issue_52304[4c6d]::example::{closure#0}), [(), (), &'{erased} i32, (), CoroutineWitness(DefId(0:6 ~ issue_52304[4c6d]::example::{closure#0}), []), ()])), Subtype, Term::Ty(Alias(Opaque, AliasTy { args: [], def_id: DefId(0:5 ~ issue_52304[4c6d]::example::{opaque#0}), .. }))), bound_vars: [] }
```
Ignoring the fact that we end up stalling some really dumb obligations here (lol), I think it makes more sense for us to be using post borrowck analysis for this check anyways.
r? lcnr
inline_threshold mark deprecated
no-stack-check
print deprecation message for -Car too
inline_threshold deprecated and do nothing: make in untracked
make OptionDesc struct from tuple
A few borrowck tweaks to improve 2024 edition migration lints
See first two commits' changes to test outputs. Test coverage in this area is kinda weak, but I think it affects more cases than this (like the craters that will begin to trigger the `tail_expr_drop_order` tests in #134523).
Third commit is a drive-by change that removes a deref hack from `UseSpans` which doesn't really improve diagnostics much.
Mention `unnameable_types` in `unreachable_pub` documentation.
This link makes sense because someone who wishes to avoid unusable `pub` is likely, but not guaranteed, to be interested in avoiding unnameable types.
Also fixed some grammar problems I noticed in the area.
Fixes#116604.
r? Urgau
add m68k-unknown-none-elf target
r? `@workingjubilee`
The existing `m68k-unknown-linux-gnu` target builds `std` by default, requires atomics, and has a base cpu with an fpu. A smaller/more embedded target is desirable both to have a baseline target for the ISA, as well to make debugging easier for working on the llvm backend. Currently this target is using the `M68010` as the minimum CPU due, but as missing features are merged into the `M68k` llvm backend I am hoping to lower this further.
I have been able to build very small crates using a toolchain built against this target (together with a later version of `object`) using the configuration described in the target platform-support documentation, although getting anything of substantial complexity to build quickly hits errors in the llvm backend
This link makes sense because someone who wishes to avoid unusable `pub`
is likely, but not guaranteed, to be interested in avoiding unnameable
types.
Also fixed some grammar problems I noticed in the area.
Fixes#116604.
cg_llvm: Use constants for DWARF opcodes, instead of FFI calls
Split off from #134009 to incorporate feedback from https://github.com/rust-lang/rust/pull/134009#discussion_r1903133906.
Most of the constant values now come from gimli, which is already a compiler dependency.
I noticed that `DW_OP_LLVM_fragment` is an LLVM detail that is not defined by DWARF and could hypothetically change, so I added a static assertion on the C++ side to detect that if it ever happens.
r? workingjubilee
Add a notion of "some ABIs require certain target features"
I think I finally found the right shape for the data and checks that I recently added in https://github.com/rust-lang/rust/pull/133099, https://github.com/rust-lang/rust/pull/133417, https://github.com/rust-lang/rust/pull/134337: we have a notion of "this ABI requires the following list of target features, and it is incompatible with the following list of target features". Both `-Ctarget-feature` and `#[target_feature]` are updated to ensure we follow the rules of the ABI. This removes all the "toggleability" stuff introduced before, though we do keep the notion of a fully "forbidden" target feature -- this is needed to deal with target features that are actual ABI switches, and hence are needed to even compute the list of required target features.
We always explicitly (un)set all required and in-conflict features, just to avoid potential trouble caused by the default features of whatever the base CPU is. We do this *before* applying `-Ctarget-feature` to maintain backward compatibility; this poses a slight risk of missing some implicit feature dependencies in LLVM but has the advantage of not breaking users that deliberately toggle ABI-relevant target features. They get a warning but the feature does get toggled the way they requested.
For now, our logic supports x86, ARM, and RISC-V (just like the previous logic did). Unsurprisingly, RISC-V is the nicest. ;)
As a side-effect this also (unstably) allows *enabling* `x87` when that is harmless. I used the opportunity to mark SSE2 as required on x86-64, to better match the actual logic in LLVM and because all x86-64 chips do have SSE2. This infrastructure also prepares us for requiring SSE on x86-32 when we want to use that for our ABI (and for float semantics sanity), see https://github.com/rust-lang/rust/issues/133611, but no such change is happening in this PR.
r? `@workingjubilee`
Target: Add mips mti baremetal support
Do the same thing as gcc, which use the vendor `mti` to mark the toolchain as MIPS32r2 default.
We support both big endian and little endian flavor:
mips-mti-none-elf
mipsel-mti-none-elf
[Debuginfo] Force enum `DISCR_*` to `static const u64` to allow for inspection via LLDB
see [here](https://rust-lang.zulipchat.com/#narrow/channel/317568-t-compiler.2Fwg-debugging/topic/Revamping.20Debuginfo/near/486614878) for more info.
This change mainly helps `*-msvc` debugged with LLDB. Currently, LLDB cannot inspect `static` struct fields, so the intended visualization for enums is only borderline functional, and niche enums with ranges of discriminant cannot be determined at all .
LLDB *can* inspect `static const` values (though for whatever reason, non-enum/non-u64 consts don't work).
This change adds the `LLVMRustDIBuilderCreateQualifiedType` to the rust FFI layer to wrap the discr type with a `const` modifier, as well as forcing all generated integer enum `DISCR_*` values to be u64's. Those values will only ever be used by debugger visualizers anyway, so it shouldn't be a huge deal, but I left a fixme comment for it just in case.. The `tag` also still properly reflects the discriminant type, so no information is lost.
turn rustc_box into an intrinsic
I am not entirely sure why this was made a special magic attribute, but an intrinsic seems like a more natural way to add magic expressions to the language.
Pass the arch rather than full target name to windows_registry::find_tool
The full target name can be anything with custom target specs. Passing just the arch wasn't possible before cc 1.2, but is now thanks to https://github.com/rust-lang/cc-rs/pull/1285.
try-job: i686-msvc
rustc_intrinsic: support functions without body
We synthesize a HIR body `loop {}` but such bodyless intrinsics.
Most of the diff is due to turning `ItemKind::Fn` into a brace (named-field) enum variant, because it carries a `bool`-typed field now. This is to remember whether the function has a body. MIR building panics to avoid ever translating the fake `loop {}` body, and the intrinsic logic uses the lack of a body to implicitly mark that intrinsic as must-be-overridden.
I first tried actually having no body rather than generating the fake body, but there's a *lot* of code that assumes that all function items have HIR and MIR, so this didn't work very well. Then I noticed that even `rustc_intrinsic_must_be_overridden` intrinsics have MIR generated (they are filled with an `Unreachable` terminator) so I guess I am not the first to discover this. ;)
r? `@oli-obk`
Rollup of 7 pull requests
Successful merges:
- #133964 (core: implement `bool::select_unpredictable`)
- #135001 (Allow using self-contained LLD in bootstrap)
- #135055 (Report impl method has stricter requirements even when RPITIT inference gets in the way)
- #135064 (const-in-pattern: test that the PartialEq impl does not need to be const)
- #135066 (bootstrap: support `./x check run-make-support`)
- #135069 (remove unused function params)
- #135084 (Update carrying_mul_add test to tolerate `nuw`)
r? `@ghost`
`@rustbot` modify labels: rollup
const-in-pattern: test that the PartialEq impl does not need to be const
Fixes https://github.com/rust-lang/rust/issues/119398 by adding a test.
`@compiler-errors` is there some place in the code where we could add a comment saying "as a backcompat hack, here we only require `PartialEq` and not `const PartialEq`"?
r? `@compiler-errors`
Project to `TyKind::Error` when there are unconstrained non-lifetime (ty/const) impl params
It splits the `enforce_impl_params_are_constrained` function into lifetime/non-lifetime, and queryfies the latter. We can then use the result of the latter query (`Result<(), ErrorGuaranteed>`) to intercept projection and constrain the projected type to `TyKind::Error`, which ensures that we leak no ty or const vars to places that don't expect them, like `normalize_erasing_regions`.
The reason we split `enforce_impl_params_are_constrained` into two parts is because we only error for *lifetimes* if the lifetime ends up showing up in any of the associated types of the impl (e.g. we allow `impl<'a> Foo { type Assoc = (); }`). However, in order to compute the `type_of` query for the anonymous associated type of an RPITIT, we need to do trait solving (in `query collect_return_position_impl_trait_in_trait_tys`). That would induce cycles. Luckily, it turns out for lifetimes we don't even care about if they're unconstrained, since they're erased in all contexts that we are trying to fix ICEs. So it's sufficient to keep this check separated out of the query.
I think this is a bit less invasive of an approach compared to #127973. The major difference between this PR and that PR is that we queryify the check instead of merging it into the `explicit_predicates_of` query, and we use the result to taint just projection goals, rather than trait goals too. This doesn't require a lot of new tracking in `ItemCtxt` and `GenericPredicates`, and it also seems to not require any other changes to typeck like that PR did.
Fixes#123141Fixes#125874Fixes#126942Fixes#127804Fixes#130967
r? oli-obk
Improve infer (`_`) suggestions in `const`s and `static`s
Fixes https://github.com/rust-lang/rust/issues/135010.
This PR does a few things to (imo) greatly improve the error message when users write something like `static FOO: [i32; _] = [1, 2, 3]`.
Firstly, it adapts the recovery code for when we encounter `_` in a const/static to work a bit more like `fn foo() -> _`, and removes the somewhat redundant query `diagnostic_only_typeck`.
Secondly, it changes the lowering for `[T; _]` to always lower under the `feature(generic_arg_infer)` logic to `ConstArgKind::Infer`. We still issue the feature error, so it's not doing anything *observable* on the good path, but it does mean that we no longer erroneously interpret `[T; _]`'s array length as a `_` **wildcard expression** (à la destructuring assignment, like `(_, y) = expr`).
Lastly it makes the suggestions verbose and fixes (well, suppresses) a bug with stashing and suggestions.
r? oli-obk
Some type-outlives computation tweaks
Some tweaks that I wrote when investigating https://github.com/rust-lang/rust/issues/135006.
The only commit that's probably interesting here is f3646748cd (the first commit). For some reason it was concerned with filtering out param-env outlives clauses when they matched item-bound outlives clauses. However, if you look at the rest of the control flow for that function, not filtering out those bounds doesn't actually affect the behavior materially.
Pass objcopy args for stripping on OSX
When `-Cstrip` was changed in #131405 to use the bundled rust-objcopy instead of /usr/bin/strip on OSX, strip-like arguments were preserved.
But strip and objcopy are, while being the same binary, different, they have different defaults depending on which binary they are. Notably, strip strips everything by default, and objcopy doesn't strip anything by default.
Additionally, `-S` actually means `--strip-all`, so debuginfo stripped everything and symbols didn't strip anything.
We now correctly pass `--strip-debug` and `--strip-all`.
fixes#135028
try-job: aarch64-apple
try-job: dist-aarch64-apple
Do the same thing as gcc, which use the vendor `mti` to mark
the toolchain as MIPS32r2 default.
We support both big endian and little endian flavor:
mips-mti-none-elf
mipsel-mti-none-elf
taint fcx on selection errors during unsizing
With `feature(dyn_compatible_for_dispatch)` we only check for dyn-compatibility by checking the `T: Unsize<dyn Trait>` predicate during the unsizing coercions checks. If the predicate doesn't hold, we emit an error, but pretend the coercion succeeded to prevent further errors. To prevent const eval from attempting to actually perform this coercion, we need to taint the fcx after reporting the trait errors in the coercion check.
fixes https://github.com/rust-lang/rust/issues/135021
fixes https://github.com/rust-lang/rust/issues/130521
When `-Cstrip` was changed to use the bundled rust-objcopy instead of
/usr/bin/strip on OSX, strip-like arguments were preserved.
But strip and objcopy are, while being the same binary, different, they
have different defaults depending on which binary they are.
Notably, strip strips everything by default, and objcopy doesn't strip
anything by default.
Additionally, `-S` actually means `--strip-all`, so debuginfo stripped
everything and symbols didn't strip anything.
We now correctly pass `--strip-debug` and `--strip-all`.
Range metadata was disabled for amdgpu due to a backend bug. I did not
encounter any problems when removing the workaround to enable range
metadata (tried compiling `core` and `alloc`), so I assume this has
been fixed in LLVM in the last years.
Remove the workaround to re-enable range metadata.
Autodiff Upstreaming - rustc_codegen_llvm changes
Now that the autodiff/Enzyme backend is merged, this is an upstream PR for the `rustc_codegen_llvm` changes.
It also includes small changes to three files under `compiler/rustc_ast`, which overlap with my frontend PR (https://github.com/rust-lang/rust/pull/129458).
Here I only include minimal definitions of structs and enums to be able to build this backend code.
The same goes for minimal changes to `compiler/rustc_codegen_ssa`, the majority of changes there will be in another PR, once either this or the frontend gets merged.
We currently have 68 files left to merge, 19 in the frontend PR, 21 (+3 from the frontend) in this PR, and then ~30 in the middle-end.
This PR is large because it includes two of my three large files (~800 loc each). I could also first only upstream enzyme_ffi.rs, but I think people might want to see some use of these bindings in the same PR?
To already highlight the things which reviewers might want to discuss:
1) `enzyme_ffi.rs`: I do have a fallback module to make sure that we don't link rustc against Enzyme when we build rustc without autodiff support.
2) `add_panic_msg_to_global` was a pain to write and I currently can't even use it. Enzyme writes gradients into shadow memory. Pass in one float scalar? We'll allocate and return an extra float telling you how this float affected the output. Pass in a slice of floats? We'll let you allocate the vector and pass in a mutable reference to a float slice, we'll then write the gradient into that slice. It should be at least as large as your original slice, so we check that and panic if not. Currently we panic silently, but I already generate a nicer panic message with this function. I just don't know how to print it to the user. yet. I discussed this with a few rustc devs and the best we could come up with (for now), was to look for mangled panic calls in the IR and pick one, which works surprisingly reliably. If someone knows a good way to clean this up and print the panic message I'm all in, otherwise I can remove the code that writes the nicer panic message and keep the silent panic, since it's enough for soundness. Especially since this PR is already a bit larger.
3) `SanitizeHWAddress`: When differentiating C++, Enzyme can use TBAA to "understand" enums/unions, but for Rust we don't have this information. LLVM might to speculative loads which (without TBAA) confuse Enzyme, so we disable those with this attribute. This attribute is only set during the first opt run before Enzyme differentiates code. We then remove it again once we are done with autodiff and run the opt pipeline a second time. Since enums are everywhere in Rust, support for them is crucial, but if this looks too cursed I can remove these ~100 lines and keep them in my fork for now, we can then discuss them separately to make this PR simpler?
4) Duplicated llvm-opt runs: Differentiating already optimized code (and being able to do additional optimizations on the fly, e.g. for GPU code) is _the_ reason why Enzyme is so fast, so the compile time is acceptable for autodiff users: https://enzyme.mit.edu/talks/Publications/ (There are also algorithmic issues in Enzyme core which are more serious than running opt twice).
5) I assume that if we merge these minimal cg_ssa changes here already, I also need to fix the other backends (GCC and cliff) to have dummy implementations, correct?
6) *I'm happy to split this PR up further if reviewers have recommendations on how to.*
For the full implementation, see: https://github.com/rust-lang/rust/pull/129175
Tracking:
- https://github.com/rust-lang/rust/issues/124509
Provide structured suggestion for `impl Default` of type where all fields have defaults
```
error: `Default` impl doesn't use the declared default field values
--> $DIR/manual-default-impl-could-be-derived.rs:28:1
|
LL | / impl Default for B {
LL | | fn default() -> Self {
LL | | B {
LL | | x: s(),
| | --- this field has a default value
LL | | y: 0,
| | - this field has a default value
... |
LL | | }
| |_^
|
help: to avoid divergence in behavior between `Struct { .. }` and `<Struct as Default>::default()`, derive the `Default`
|
LL ~ #[derive(Default)] struct B {
|
```
Note that above the structured suggestion also includes completely removing the manual `impl`, but the rendering doesn't.
Some small nits to the borrowck suggestions for mutating a map through index
1. Suggesting users to either use `.insert` or `.get_mut` (which do totally different things) can be a bit of a footgun, so let's make that a bit more nuanced.
2. I find the suggestion of `.get_mut(|val| { *val = whatever; })` to be a bit awkward. I changed this to be an if-let instead.
3. Fix a bug which was suppressing the structured suggestion for some mutations via the index operator on `HashMap`/`BTreeMap`.
r? estebank or reassign
E0277: suggest dereferencing function arguments in more cases
This unifies and generalizes some of the logic in `TypeErrCtxt::suggest_dereferences` so that it will suggest dereferencing arguments to function/method calls in order to satisfy trait bounds in more cases.
Previously it would only fire on reference types, and it had two separate cases (one specifically to get through custom `Deref` impls when passing by-reference, and one specifically to catch #87437). I've based the new checks loosely on what's done for `E0308` in `FnCtxt::suggest_deref_or_ref`: it will suggest dereferences to satisfy trait bounds whenever the referent is `Copy`, is boxed (& so can be moved out of the boxes), or is being passed by reference.
This doesn't make the suggestion fire in contexts other than function arguments or binary operators (which are in a separate case that this doesn't touch), and doesn't make it suggest a combination of `&`-removal and dereferences. Those would require a bit more restructuring, so I figured just doing this would be a decent first step.
Closes#90997
borrowck diagnostics: make `add_move_error_suggestions` use the HIR rather than `SourceMap`
This PR aims to fix#132806 by rewriting `add_move_error_suggestions`[^1]. Previously, it manually scanned the source text to find a leading `&`, which isn't always going to produce a correct result (see: that issue). Admittedly, the HIR visitor in this PR introduces a lot of boilerplate, but hopefully the logic at its core isn't too complicated (I go over it in the comments). I also tried a simpler version that didn't use a HIR visitor and suggested adding `ref` always, but the `&ref x` suggestions really didn't look good. As a bonus for the added complexity though, it's now able to produce nice `&`-removing suggestions in more cases.
I tried to do this such that it avoids edition-dependent checks and its suggestions can be applied together with those from the match ergonomics 2024 migration lint. I haven't added tests for that since the details of match ergonomics 2024 are still being sorted out, but I can try if desired once that's finalized.
[^1]: In brief, it fires on patterns where users try to bind by-value in such a way that moves out of a reference to a non-Copy type (including slice references with non-copy elements). The suggestions are to change the binding's mode to be by-reference, either by removing[^2] an enclosing `&`/`&mut` or adding `ref` to the binding.
[^2]: Incidentally, I find the terminology of "consider removing the borrow" a bit confusing for a suggestion to remove a `&` pattern in order to make bindings borrow rather than move. I'm not sure what a good, concise way to explain that would be though, and that should go in a separate PR anyway.
```
error: `Default` impl doesn't use the declared default field values
--> $DIR/manual-default-impl-could-be-derived.rs:28:1
|
LL | / impl Default for B {
LL | | fn default() -> Self {
LL | | B {
LL | | x: s(),
| | --- this field has a default value
LL | | y: 0,
| | - this field has a default value
... |
LL | | }
| |_^
|
help: to avoid divergence in behavior between `Struct { .. }` and `<Struct as Default>::default()`, derive the `Default`
|
LL ~ #[derive(Default)] struct B {
|
```
Note that above the structured suggestion also includes completely removing the manual `impl`, but the rendering doesn't.
Account for C string literals and `format_args` in `HiddenUnicodeCodepoints` lint
This is stacked on #134955, and either that can land first or both of them can land together here. I split this out because this is a bit more involved of an impl.
Fixes#94945
