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2025-09-09Auto merge of #145717 - BoxyUwU:erase_regions_rename, r=lcnrbors-16/+23
rename erase_regions to erase_and_anonymize_regions I find it consistently confusing that `erase_regions` does more than replacing regions with `'erased`. it also makes some code look real goofy to be writing manual folders to erase regions with a comment saying "we cant use erase regions" :> or code that re-calls erase_regions on types with regions already erased just to anonymize all the bound regions. r? lcnr idk how i feel about the name being almost twice as long now
2025-09-09Driveby fixesBoxy-0/+2
2025-09-09erase_regions to erase_and_anonymize_regionsBoxy-16/+21
2025-09-09Rollup merge of #145819 - jdonszelmann:convert-limits, r=fmeaseStuart Cook-2/+2
Port limit attributes to the new attribute parsing infrastructure Doesn't pass tests, to be rebased on https://github.com/rust-lang/rust/pull/145792 which will solve that r? `@fmease`
2025-09-08fixup limit handling codeJana Dönszelmann-2/+2
2025-09-08reviewlcnr-2/+3
2025-09-08optimize `CanonicalVarValues::instantiate`lcnr-3/+2
2025-09-08pass `sub_relations` into canonical querieslcnr-2/+3
2025-09-08eagerly compute `sub_relations` againlcnr-98/+7
2025-09-06Rollup merge of #144801 - estebank:issue-144734, r=spastorinoMatthias Krüger-10/+68
Suggest bounds in more cases, accounting for type parameters referenced in predicate Use a `ty::Visitor` to see if the failed predicate references a type parameter. If it does, then we only suggest adding a bound to an (associated) item only if the referenced parameter is present in its generics. Provide adding bound suggestion in trait and impl associated functions in cases we previously weren't: ``` error[E0277]: `?` couldn't convert the error to `ApplicationError` --> $DIR/suggest-complex-bound-on-method.rs:18:16 | LL | t.run()?; | -----^ the trait `From<<T as Trait>::Error>` is not implemented for `ApplicationError` | | | this can't be annotated with `?` because it has type `Result<_, <T as Trait>::Error>` | note: `ApplicationError` needs to implement `From<<T as Trait>::Error>` --> $DIR/suggest-complex-bound-on-method.rs:12:1 | LL | enum ApplicationError { | ^^^^^^^^^^^^^^^^^^^^^ = note: the question mark operation (`?`) implicitly performs a conversion on the error value using the `From` trait help: consider introducing a `where` clause, but there might be an alternative better way to express this requirement | LL | fn thing<T: Trait>(&self, t: T) -> Result<(), ApplicationError> where ApplicationError: From<<T as Trait>::Error> { | +++++++++++++++++++++++++++++++++++++++++++++++++ ``` Fix rust-lang/rust#144734.
2025-09-05remove couple of clonesMatthias Krüger-1/+1
2025-09-02Auto merge of #145951 - lcnr:proof-tree-as-query, r=compiler-errorsbors-12/+22
cleanup and cache proof tree building There's some cruft left over from when we had deep proof trees. We never encounter overflow when evaluating proof trees. Even if the recursion limit is `0`, we still only hit the overflow limit when evaluating nested goals of the root. The root goal simply inherits the `root_depth` of the `SearchGraph`. Split `evaluate_root_goal_for_proof_tree` from the rest of the trait solver. This enables us to simplify the implementation of `evaluate_goal_raw` and the `ProofTreeBuilder` as we no longer need to manually track the state of the builder and can instead use separate types for that. It does require making a few internal methods into associated functions taking a `delegate` and a `span` instead of the `EvalCtxt` itself. I've also split `SearchGraph::evaluate_goal` and `SearchGraph::evaluate_root_goal_for_proof_tree` for the same reason. Both functions don't actually share too much code, so by splitting them each version gets significantly easier to read. Add a `query evaluate_root_goal_for_proof_tree_raw` to cache proof tree building. This requires arena allocating `inspect::Probe`. I've added a new type alias `I::ProbeRef` for this. We may need to adapt this for rust-analyzer? It would definitely be easy to remove the `Copy` bound here :thinking:
2025-09-02Revert introduction of `[workspace.dependencies]`.Nicholas Nethercote-3/+3
This was done in #145740 and #145947. It is causing problems for people using r-a on anything that uses the rustc-dev rustup package, e.g. Miri, clippy. This repository has lots of submodules and subtrees and various different projects are carved out of pieces of it. It seems like `[workspace.dependencies]` will just be more trouble than it's worth.
2025-08-31Split `ObligationCauseCode::BinOp` for unops to `UnOp`Esteban Küber-19/+12
2025-08-30Detect negative literal inferred to unsigned integerEsteban Küber-1/+40
``` error[E0277]: the trait bound `usize: Neg` is not satisfied --> $DIR/negative-literal-infered-to-unsigned.rs:2:14 | LL | for x in -5..5 { | ^^ the trait `Neg` is not implemented for `usize` | help: consider specifying an integer type that can be negative | LL | for x in -5isize..5 { | +++++ ```
2025-08-29cleanup proof tree implementation and add cachelcnr-12/+22
2025-08-28Auto merge of #145807 - zachs18:only-consider-auto-traits-empty, ↵bors-1/+6
r=compiler-errors When determining if a trait has no entries for the purposes of omitting vptrs from subtrait vtables, consider its transitive supertraits' entries, instead of just its own entries. When determining if a non-first supertrait vptr can be omitted from a subtrait vtable, check if the supertrait or any of its (transitive) supertraits have methods, instead of only checking if the supertrait itself has methods. This fixes the soundness issue where a vptr would be omitted for a supertrait with no methods but that itself had a supertrait with methods, while still optimizing the case where the supertrait is "truly" empty (it has no own vtable entries, and none of its (transitive) supertraits have any own vtable entries). Fixes <https://github.com/rust-lang/rust/issues/145752> ----- Old description: ~~Treat all non-auto traits as non-empty (possibly having methods) for purposes of determining if we need to emit a vptr for a non-direct supertrait (and for new "sibling" entries after a direct or non-direct supertrait).~~ This fixes (I believe) the soundness issue, ~~but regresses vtable sizes and possibly upcasting perf in some cases when using trait hierarchies with empty non-auto traits (see `tests/ui/traits/vtable/multiple-markers.stderr`) since we use vptrs in some cases where we could re-use the vtable.~~ Fixes <https://github.com/rust-lang/rust/issues/145752> Re-opens (not anymore) <https://github.com/rust-lang/rust/issues/114942> Should not affect <https://github.com/rust-lang/rust/issues/131813> (i.e. the soundness issue is still fixed, ~~though the relevant vtables in the `trait Evil` example will be larger now~~) cc implementation history <https://github.com/rust-lang/rust/pull/131864> <https://github.com/rust-lang/rust/pull/113856> ----- ~~It should be possible to check if a trait has any methods from itself *or* supertraits (instead of just from itself), but to fix the immediate soundness issue, just assume any non-auto trait could have methods. A more optimistic check can be implemented later (or if someone does it soon it could just supercede this PR :smile:).~~ Done in latest push `@rustbot` label A-dyn-trait F-trait_upcasting
2025-08-27Add `itertools` to `[workspace.dependencies]`.Nicholas Nethercote-1/+1
2025-08-27Add `tracing` to `[workspace.dependencies]`.Nicholas Nethercote-1/+1
2025-08-27Add `thin-vec` to newly added `[workspace.dependencies]`.Nicholas Nethercote-1/+1
2025-08-26Rollup merge of #145481 - mu001999-contrib:fix/closure-sugg, r=SparrowLiiGuillaume Gomez-6/+10
Add parentheses for closure when suggesting calling closure Fixes rust-lang/rust#145404
2025-08-25Only consider auto traits empty for the purposes of omitting vptrs from ↵Zachary S-1/+6
subtrait vtables
2025-08-25change non-defining use error messagelcnr-2/+26
2025-08-25support non-defining uses in HIR typecklcnr-12/+14
2025-08-23Auto merge of #145706 - lcnr:uniquification, r=BoxyUwUbors-11/+18
change HIR typeck region uniquification handling approach rust-lang/rust#144405 causes structural lookup of opaque types to not work during HIR typeck, so instead avoid uniquifying goals and instead only reprove them if MIR borrowck actually encounters an error. This doesn't perfectly maintain the property that HIR typeck succeeding implies that MIR typeck succeeds, instead weakening this check to only guarantee that HIR typeck implies that MIR typeck succeeds modulo region uniquification. This means we still get the actually desirable ICEs if we MIR building is broken or we forget to check some property in HIR typeck, without having to deal with the fallout of uniquification in HIR typeck itself. We report errors using the original obligation sources of HIR typeck so diagnostics aren't that negatively impacted either. Here's the history of region uniquification while working on the new trait solver: - rust-lang/rust#107981 - rust-lang/rust#110180 - rust-lang/rust#114117 - rust-lang/rust#130821 - rust-lang/rust#144405 - rust-lang/rust#145706 <- we're here :tada: r? `@BoxyUwU`
2025-08-22Rollup merge of #145641 - estebank:point-at-type-in-e0277, r=davidtwcoJacob Pratt-55/+88
On E0277, point at type that doesn't implement bound When encountering an unmet trait bound, point at local type that doesn't implement the trait: ``` error[E0277]: the trait bound `Bar<T>: Foo` is not satisfied --> $DIR/issue-64855.rs:9:19 | LL | pub struct Bar<T>(<Self as Foo>::Type) where Self: ; | ^^^^^^^^^^^^^^^^^^^ unsatisfied trait bound | help: the trait `Foo` is not implemented for `Bar<T>` --> $DIR/issue-64855.rs:9:1 | LL | pub struct Bar<T>(<Self as Foo>::Type) where Self: ; | ^^^^^^^^^^^^^^^^^ ```
2025-08-22On E0277, point at type that doesn't implement boundEsteban Küber-55/+88
When encountering an unmet trait bound, point at local type that doesn't implement the trait: ``` error[E0277]: the trait bound `Bar<T>: Foo` is not satisfied --> $DIR/issue-64855.rs:9:19 | LL | pub struct Bar<T>(<Self as Foo>::Type) where Self: ; | ^^^^^^^^^^^^^^^^^^^ unsatisfied trait bound | help: the trait `Foo` is not implemented for `Bar<T>` --> $DIR/issue-64855.rs:9:1 | LL | pub struct Bar<T>(<Self as Foo>::Type) where Self: ; | ^^^^^^^^^^^^^^^^^ ```
2025-08-22change HIR typeck unification handling approachlcnr-11/+18
2025-08-22Add an experimental unsafe(force_target_feature) attribute.Luca Versari-1/+1
This uses the feature gate for https://github.com/rust-lang/rust/issues/143352, but is described in https://github.com/rust-lang/rfcs/pull/3820 which is strongly tied to the experiment.
2025-08-21Auto merge of #145701 - jhpratt:rollup-a0kg33p, r=jhprattbors-5/+24
Rollup of 19 pull requests Successful merges: - rust-lang/rust#143383 (stabilize `const_array_each_ref`) - rust-lang/rust#144758 ([Doc] Add links to the various collections) - rust-lang/rust#144915 (Defer tail call ret ty equality to check_tail_calls) - rust-lang/rust#145256 (Add new `--test-codegen-backend` bootstrap option) - rust-lang/rust#145297 (fix(debuginfo): handle false positives in overflow check) - rust-lang/rust#145390 (Shorten some dependency chains in the compiler) - rust-lang/rust#145415 (std_detect: RISC-V: implement implication to "C") - rust-lang/rust#145525 (stdlib: Replace typedef -> type alias in doc comment) - rust-lang/rust#145590 (Prevent impossible combinations in `ast::ModKind`.) - rust-lang/rust#145593 (UnsafePinned::raw_get: sync signature with get) - rust-lang/rust#145621 (Fix some doc typos) - rust-lang/rust#145627 (Unconditionally-const supertraits are considered not dyn compatible) - rust-lang/rust#145642 (Do not use effective_visibilities query for Adt types of a local trait while proving a where-clause) - rust-lang/rust#145650 (Fix JS search scripts path) - rust-lang/rust#145654 (Download CI GCC into the correct directory) - rust-lang/rust#145662 (Enforce correct number of arguments for `"x86-interrupt"` functions) - rust-lang/rust#145673 (Add flock support for cygwin) - rust-lang/rust#145674 (Enable triagebot `[review-changes-since]` feature) - rust-lang/rust#145678 (Fix typo in docstring) r? `@ghost` `@rustbot` modify labels: rollup
2025-08-21Rollup merge of #145642 - xizheyin:145611, r=lcnrJacob Pratt-1/+1
Do not use effective_visibilities query for Adt types of a local trait while proving a where-clause Partially fix rust-lang/rust#145611, but we should do something make cycle in this situation ICE. Instead of using a query, call `&tcx.resolutions(()).effective_visibilities`. r? `````@lcnr````` cc `````@compiler-errors`````
2025-08-21Rollup merge of #145627 - compiler-errors:const-supertrait-dyn-compat, ↵Jacob Pratt-4/+23
r=fee1-dead Unconditionally-const supertraits are considered not dyn compatible Let's save some space in the design of const traits by making `dyn Trait` where `trait Trait: const Super` not dyn compatible. Such a trait cannot satisfy `dyn Trait: Trait`; we could in the future make this dyn compatible but *NOT* implement `Trait`, but that's a bit weird and seems like it needs to be independently justified moving forward. Fixes https://github.com/rust-lang/rust/issues/145198 r? fee1-dead
2025-08-20Unconditionally-const supertraits are considered not dyn compatibleMichael Goulet-4/+23
2025-08-20Do not use effective_visibilities query for Adt types of a local trait while ↵xizheyin-1/+1
proving a where-clause Signed-off-by: xizheyin <xizheyin@smail.nju.edu.cn>
2025-08-20handle opaque types before region inferencelcnr-0/+1
2025-08-19Rollup merge of #145537 - zachs18:metasized-negative-bound-fix, r=davidtwco许杰友 Jieyou Xu (Joe)-3/+5
Do not consider a `T: !Sized` candidate to satisfy a `T: !MetaSized` obligation. This example should fail to compile (and does under this PR, with the old and new solvers), but currently compiles successfully ([playground](https://play.rust-lang.org/?version=nightly&mode=debug&edition=2024&gist=6e0e5d0ae0cdf0571dea97938fb4a86d)), because (IIUC) the old solver's `lazily_elaborate_sizedness_candidate`/callers and the new solver's `TraitPredicate::fast_reject_assumption`/`match_assumption` consider a `T: _ Sized` candidate to satisfy a `T: _ MetaSized` obligation, for either polarity `_`, when that should only hold for positive polarity. ```rs #![feature(negative_bounds)] #![feature(sized_hierarchy)] use std::marker::MetaSized; fn foo<T: !MetaSized>() {} fn bar<T: !Sized + MetaSized>() { foo::<T>(); //~^ ERROR the trait bound `T: !MetaSized` is not satisfied // error under this PR } ``` Only observable with the internal-only `feature(negative_bounds)`, so might just be "wontfix". This example is added as a test in this PR (as well as testing that `foo<()>` and `foo<str>` are disallowed for `fn foo<T: !MetaSized`). cc `@davidtwco` for `feature(sized_hierarchy)` Maybe similar to 91c53c9 from <https://github.com/rust-lang/rust/pull/143307>
2025-08-19Rollup merge of #145338 - lcnr:coroutine-witness-yikes, r=compiler-errors许杰友 Jieyou Xu (Joe)-43/+18
actually provide the correct args to coroutine witnesses rust-lang/rust#145194 accidentally provided all arguments of the closure to the witness, but the witness only takes the generic parameters of the defining scope: https://github.com/rust-lang/rust/blob/216cdb7b22b637cef75b7225c642cb7587192643/compiler/rustc_hir_typeck/src/closure.rs#L164 Fixes rust-lang/rust#145288
2025-08-17Do not consider a `T: !Sized` candidate to satisfy a `T: !MetaSized` obligation.Zachary S-3/+5
2025-08-17Auto merge of #145284 - nnethercote:type_name-print-regions, r=lcnrbors-4/+4
Print regions in `type_name`. Currently they are skipped, which is a bit weird, and it sometimes causes malformed output like `Foo<>` and `dyn Bar<, A = u32>`. Most regions are erased by the time `type_name` does its work. So all regions are now printed as `'_` in non-optional places. Not perfect, but better than the status quo. `c_name` is updated to trim lifetimes from MIR pass names, so that the `PASS_NAMES` sanity check still works. It is also renamed as `simplify_pass_type_name` and made non-const, because it doesn't need to be const and the non-const implementation is much shorter. The commit also renames `should_print_region` as `should_print_optional_region`, which makes it clearer that it only applies to some regions. Fixes rust-lang/rust#145168. r? `@lcnr`
2025-08-16Add parentheses for closure when suggesting calling closureMu001999-6/+10
2025-08-15Rollup merge of #145235 - compiler-errors:comment, r=BoxyUwUStuart Cook-27/+1
Minor `[const]` tweaks Self explanatory
2025-08-15Rollup merge of #122661 - estebank:assert-macro-span, r=petrochenkovStuart Cook-4/+36
Change the desugaring of `assert!` for better error output In the desugaring of `assert!`, we now expand to a `match` expression instead of `if !cond {..}`. The span of incorrect conditions will point only at the expression, and not the whole `assert!` invocation. ``` error[E0308]: mismatched types --> $DIR/issue-14091.rs:2:13 | LL | assert!(1,1); | ^ expected `bool`, found integer ``` We no longer mention the expression needing to implement the `Not` trait. ``` error[E0308]: mismatched types --> $DIR/issue-14091-2.rs:15:13 | LL | assert!(x, x); | ^ expected `bool`, found `BytePos` ``` Now `assert!(val)` desugars to: ```rust match val { true => {}, _ => $crate::panic::panic_2021!(), } ``` Fix #122159.
2025-08-14Print regions in `type_name`.Nicholas Nethercote-4/+4
Currently they are skipped, which is a bit weird, and it sometimes causes malformed output like `Foo<>` and `dyn Bar<, A = u32>`. Most regions are erased by the time `type_name` does its work. So all regions are now printed as `'_` in non-optional places. Not perfect, but better than the status quo. `c_name` is updated to trim lifetimes from MIR pass names, so that the `PASS_NAMES` sanity check still works. It is also renamed as `simplify_pass_type_name` and made non-const, because it doesn't need to be const and the non-const implementation is much shorter. The commit also renames `should_print_region` as `should_print_optional_region`, which makes it clearer that it only applies to some regions. Fixes #145168.
2025-08-14Rollup merge of #145266 - camsteffen:reduce-queries, r=petrochenkovGuillaume Gomez-1/+1
Reduce some queries around associated items
2025-08-13Rollup merge of #144949 - nnethercote:more-Printer-cleanups, r=davidtwcoGuillaume Gomez-23/+22
More `Printer` cleanups A sequel to rust-lang/rust#144776. r? ```@davidtwco```
2025-08-13Cleanup assoc parent utilsCameron Steffen-1/+1
2025-08-13`fn new_coroutine_witness_for_coroutine` woopslcnr-43/+18
2025-08-12Change the desugaring of `assert!` for better error outputEsteban Küber-4/+36
In the desugaring of `assert!`, we now expand to a `match` expression instead of `if !cond {..}`. The span of incorrect conditions will point only at the expression, and not the whole `assert!` invocation. ``` error[E0308]: mismatched types --> $DIR/issue-14091.rs:2:13 | LL | assert!(1,1); | ^ expected `bool`, found integer ``` We no longer mention the expression needing to implement the `Not` trait. ``` error[E0308]: mismatched types --> $DIR/issue-14091-2.rs:15:13 | LL | assert!(x, x); | ^ expected `bool`, found `BytePos` ``` `assert!(val)` now desugars to: ```rust match val { true => {}, _ => $crate::panic::panic_2021!(), } ``` Fix #122159. We make some minor changes to some diagnostics to avoid span overlap on type mismatch or inverted "expected"/"found" on type errors. We remove some unnecessary parens from core, alloc and miri. address review comments
2025-08-11Propagate TraitImplHeader to hirCameron Steffen-4/+4
2025-08-11Rollup merge of #145194 - compiler-errors:coro-witness-re, r=lcnrStuart Cook-2/+15
Ignore coroutine witness type region args in auto trait confirmation ## The problem Consider code like: ``` async fn process<'a>() { Box::pin(process()).await; } fn require_send(_: impl Send) {} fn main() { require_send(process()); } ``` When proving that the coroutine `{coroutine@process}::<'?0>: Send`, we end up instantiating a nested goal `{witness@process}::<'?0>: Send` by synthesizing a witness type from the coroutine's args: Proving a coroutine witness type implements an auto trait requires looking up the coroutine's witness types. The witness types are a binder that look like `for<'r> { Pin<Box<{coroutine@process}::<'r>>> }`. We instantiate this binder with placeholders and prove `Send` on the witness types. This ends up eventually needing to prove something like `{coroutine@process}::<'!1>: Send`. Repeat this process, and we end up in an overflow during fulfillment, since fulfillment does not use freshening. This can be visualized with a trait stack that ends up looking like: * `{coroutine@process}::<'?0>: Send` * `{witness@process}::<'?0>: Send` * `Pin<Box<{coroutine@process}::<'!1>>>: Send` * `{coroutine@process}::<'!1>: Send` * ... * `{coroutine@process}::<'!2>: Send` * `{witness@process}::<'!2>: Send` * ... * overflow! The problem here specifically comes from the first step: synthesizing a witness type from the coroutine's args. ## Why wasn't this an issue before? Specifically, before 63f6845e570305a92eaf855897768617366164d6, this wasn't an issue because we were instead extracting the witness from the coroutine type itself. It turns out that given some `{coroutine@process}::<'?0>`, the witness type was actually something like `{witness@process}::<'erased>`! So why do we end up with a witness type with `'erased` in its args? This is due to the fact that opaque type inference erases all regions from the witness. This is actually explicitly part of opaque type inference -- changing this to actually visit the witness types actually replicates this overflow even with 63f6845e570305a92eaf855897768617366164d6 reverted: https://github.com/rust-lang/rust/blob/ca77504943887037504c7fc0b9bf06dab3910373/compiler/rustc_borrowck/src/type_check/opaque_types.rs#L303-L313 To better understand this difference and how it avoids a cycle, if you look at the trait stack before 63f6845e570305a92eaf855897768617366164d6, we end up with something like: * `{coroutine@process}::<'?0>: Send` * `{witness@process}::<'erased>: Send` **<-- THIS CHANGED** * `Pin<Box<{coroutine@process}::<'!1>>>: Send` * `{coroutine@process}::<'!1>: Send` * ... * `{coroutine@process}::<'erased>: Send` **<-- THIS CHANGED** * `{witness@process}::<'erased>: Send` **<-- THIS CHANGED** * coinductive cycle! :tada: ## So what's the fix? This hack replicates the behavior in opaque type inference to erase regions from the witness type, but instead erasing the regions during auto trait confirmation. This is kinda a hack, but is sound. It does not need to be replicated in the new trait solver, of course. --- I hope this explanation makes sense. We could beta backport this instead of the revert https://github.com/rust-lang/rust/pull/145193, but then I'd like to un-revert that on master in this PR along with landing this this hack. Thoughts? r? lcnr