Rollup of 6 pull requests
Successful merges:
- #114178 (Account for macros when suggesting a new let binding)
- #114199 (Don't unsize coerce infer vars in select in new solver)
- #114301 (Don't check unnecessarily that impl trait is RPIT)
- #114314 (Tweaks to `adt_sized_constraint`)
- #114322 (Fix invalid slice coercion suggestion reported in turbofish)
- #114340 ([rustc_attr][nit] Replace `filter` + `is_some` with `map_or`.)
r? `@ghost`
`@rustbot` modify labels: rollup
Fix invalid slice coercion suggestion reported in turbofish
This PR fixes the invalid slice coercion suggestion reported in turbofish and inferred generics by not emitting them.
Fixes https://github.com/rust-lang/rust/issues/110063
Detect trait upcasting through struct tail unsizing in new solver select
Oops, we were able to hide trait upcasting behind a parent unsize goal that evaluated to `Certainty::Yes`. Let's do rematching for `Certainty::Yes` unsize goals with `BuiltinImplSource::Misc` sources (corresponding to all of the other unsize rules) to make sure we end up selecting any nested goals which may be satisfied via `BuiltinImplSource::TraitUpcasting` or `::TupleUnsizing`.
r? ``@lcnr``
Restore region uniquification in the new solver 🎉
All of the bugs that were "due" to uniquification have been settled via other means (e.g. bidirectional alias-relate, param-env incompleteness, etc).
Firstly, revert the functional changes in #110180. 😸
Secondly, we need to ignore regions when considering if a goal has changed (the "has_changed" boolean returned from `evaluate_goal`) -- otherwise, because we're doing region uniquification, we may perpetually consider a goal to be changed. See the UI test I committed for an explanation.
Don't treat negative trait predicates as always knowable
We don't need this. It was added in #90104 but I don't really know why. It's not sound afaict -- negative trait predicates need the same coherence-ambiguity/orphan check rules as positive ones.
r? `@lcnr`
cc `@spastorino,` do you remember why?
Double check that hidden types match the expected hidden type
Fixes https://github.com/rust-lang/rust/issues/113278 specifically, but I left a TODO for where we should also add some hardening.
It feels a bit like papering over the issue, but at least this way we don't get unsoundness, but just surprising errors. Errors will be improved and given spans before this PR lands.
r? `@compiler-errors` `@lcnr`
