fix emit_inference_failure_err ICE
#98610
Conversation
rustbot
added
the
T-compiler
|
Some changes occured in need_type_info.rs cc @lcnr |
|
(rust-highfive has picked a reviewer for you, use r? to override) |
rust-highfive
added
the
S-waiting-on-review
| error[E0282]: type annotations needed | ||
| --> $DIR/expr-struct-type-relative-gat.rs:17:9 | ||
| | | ||
| LL | Self::Output::Simple {}; | ||
| | ^^^^^^^^^^^^ cannot infer type for type parameter `T` declared on the associated type `Output` |
There was a problem hiding this comment.
We should point at Output as well.
There was a problem hiding this comment.
what exactly do you mean with this? This should suggest Self::Output::<T> but that's part of the FIXME i've added
There was a problem hiding this comment.
I meant something like
error[E0282]: type annotations needed
--> $DIR/expr-struct-type-relative-gat.rs:17:9
|
LL | type Output<T> = Bar<T>;
| - type parameter `T` that couldn't be infered on `Output`
LL | fn baz() {
LL | Self::Output::Simple {};
| ^^^^^^^^^^^^ cannot infer type for type parameter `T` declared on the associated type `Output`
as a stop gap solution, but ideally all of this would look like this
error[E0282]: type annotations needed
--> $DIR/expr-struct-type-relative-gat.rs:17:9
|
LL | type Output<T> = Bar<T>;
| - type parameter `T` that couldn't be infered on `Output`
LL | fn baz() {
LL | Self::Output::Simple {};
| ^^^^^^^^^^^^ cannot infer type for type parameter `T` declared on the associated type `Output`
help: specify the type parameter on associated type `Output`
|
LL | Self::Output::<T>::Simple {};
| +++++
Edit: although thinking about it for a second, maybe we should suggest other forms, like adding a param to baz and passing that through, I'm not sure about how GATs will actually be used in the wild to get a sense of what the appropriate suggestion might actually be.
| // FIXME: Ideally we would also deal with type relative | ||
| // paths here, even if that is quite rare. | ||
| // | ||
| // See the `need_type_info/expr-struct-type-relative-gat.rs` test | ||
| // for an example where that would be needed. | ||
| // | ||
| // However, the `type_dependent_def_id` for `Self::Output` in an | ||
| // impl is currently the `DefId` of `Output` in the trait definition | ||
| // which makes this somewhat difficult and prevents us from just | ||
| // using `self.path_inferred_subst_iter` here. | ||
| hir::ExprKind::Struct(&hir::QPath::Resolved(_self_ty, path), _, _) => { |
There was a problem hiding this comment.
Should we leave the ticket open so that the DefId of Self::Output corresponds to the impl assoc type and not the trait assoc type? That seems to be the correct fix, right?
| if let Some(ty) = self.opt_node_type(expr.hir_id) { | ||
| if let ty::Adt(_, substs) = ty.kind() { | ||
| return self.path_inferred_subst_iter(expr.hir_id, substs, path); | ||
| return Box::new(self.resolved_path_inferred_subst_iter(path, substs)); |
There was a problem hiding this comment.
Given the filtering above, this change isn't also needed, right?
There was a problem hiding this comment.
it isn't strictly needed, but it feels weird to call path_inferred_subst_iter if we already know that we're only dealing with resolved paths.
|
r? @estebank |
|
@bors r+ |
|
📌 Commit e043821 has been approved by |
bors
added
S-waiting-on-bors
…askrgr Rollup of 9 pull requests Successful merges: - rust-lang#98610 (fix `emit_inference_failure_err` ICE) - rust-lang#98640 (Let rust-analyzer ship on stable, non-preview) - rust-lang#98686 (add ice test for 46511) - rust-lang#98727 (rustdoc: filter '_ lifetimes from ty::PolyTraitRef) - rust-lang#98729 (clarify that ExactSizeIterator::len returns the remaining length) - rust-lang#98733 (Request to be notified of MIR changes) - rust-lang#98734 (Update RELEASES.md) - rust-lang#98745 (Add a `--build-dir` flag to rustbuild) - rust-lang#98749 (Add macro_rules! rustdoc change to 1.62 relnotes) Failed merges: r? `@ghost` `@rustbot` modify labels: rollup
fixes #98598
this fix doesn't make me too happy, but 🤷