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Merged
merged 1 commit into from
Sep 28, 2022
Merged

Deny associated type bindings within associated type bindings #102338

merged 1 commit into from
Sep 28, 2022

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compiler-errors
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Fixes #102335

This was made worse by #100865, which unified the way we generate substs for GATs and non-generic associated types. However, the issue was not caused by #100865, evidenced by the test I added for GATs:

trait T {
    type A: S<C<(), i32 = ()> = ()>;
    //~^ ERROR associated type bindings are not allowed here
}

trait Q {}

trait S {
    type C<T>: Q;
}

fn main() {}

^ which passes on beta (where GATs are stable) and presumably ever since GATs support was added to create_substs_for_associated_item in astconv.

@rustbot rustbot added the T-compiler Relevant to the compiler team, which will review and decide on the PR/issue. label Sep 27, 2022
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r? @jackh726

(rust-highfive has picked a reviewer for you, use r? to override)

@rust-highfive rust-highfive added the S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. label Sep 27, 2022
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r? @cjgillot since you reviewed #100865, feel free to re-roll though

@rust-highfive rust-highfive assigned cjgillot and unassigned jackh726 Sep 27, 2022
@fmease
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fmease commented Sep 27, 2022

which passes on beta (where GATs are stable)

Does this mean we should backport this PR to beta?

@compiler-errors
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Probably.

@compiler-errors compiler-errors added the beta-nominated Nominated for backporting to the compiler in the beta channel. label Sep 27, 2022
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bors commented Sep 27, 2022

☔ The latest upstream changes (presumably #102306) made this pull request unmergeable. Please resolve the merge conflicts.

@compiler-errors compiler-errors force-pushed the assoc-ty-binding-in-assoc-ty-binding branch from 5ee0422 to ca2e0bb Compare September 27, 2022 17:41
cjgillot
cjgillot reviewed Sep 27, 2022
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compiler/rustc_hir_analysis/src/astconv/mod.rs
);

let assoc_bindings = self.create_assoc_bindings_for_generic_args(item_segment.args());
if let Some(b) = assoc_bindings.first() {
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I seems wasteful to convert all bindings, just to err on the first one later. This could as well be implemented as
if let Some(b) = item_segment.args().bindings.first()
Probably better as a follow-up, as there are several instances of this pattern in the file.

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@bors r+

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bors commented Sep 27, 2022

📌 Commit ca2e0bb has been approved by cjgillot

It is now in the queue for this repository.

@bors bors added S-waiting-on-bors Status: Waiting on bors to run and complete tests. Bors will change the label on completion. and removed S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. labels Sep 27, 2022
@JohnTitor JohnTitor mentioned this pull request Sep 28, 2022
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bors added a commit to rust-lang-ci/rust that referenced this pull request Sep 28, 2022
@bors
Auto merge of rust-lang#102388 - JohnTitor:rollup-mbyw6fl, r=JohnTitor
837bf37 
Rollup of 8 pull requests

Successful merges:

 - rust-lang#100747 (Add long description and test for E0311)
 - rust-lang#102232 (Stabilize bench_black_box)
 - rust-lang#102288 (Suggest unwrapping `???<T>` if a method cannot be found on it but is present on `T`.)
 - rust-lang#102338 (Deny associated type bindings within associated type bindings)
 - rust-lang#102347 (Unescaping cleanups)
 - rust-lang#102348 (Tweak `FulfillProcessor`.)
 - rust-lang#102378 (Use already resolved `self_ty` in `confirm_fn_pointer_candidate`)
 - rust-lang#102380 (rustdoc: remove redundant mobile `.source > .sidebar` CSS)

Failed merges:

r? `@ghost`
`@rustbot` modify labels: rollup
@bors bors merged commit b263b7e into rust-lang:master Sep 28, 2022
@rustbot rustbot added this to the 1.66.0 milestone Sep 28, 2022
@matthiaskrgr
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The test crashes in rustdoc apparently 😅 #102467

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Beta backport accepted as per compiler team on Zulip

@rustbot label +beta-accepted

@rustbot rustbot added the beta-accepted Accepted for backporting to the compiler in the beta channel. label Sep 29, 2022
@compiler-errors compiler-errors mentioned this pull request Sep 29, 2022
Merged
matthiaskrgr added a commit to matthiaskrgr/rust that referenced this pull request Sep 30, 2022
@matthiaskrgr
Rollup merge of rust-lang#102492 - compiler-errors:simplify-deny-asso…
842a7d3 
…c-bindings, r=cjgillot

Don't lower assoc bindings just to deny them

Some clean-up: rust-lang#102338 (comment)
@cuviper cuviper mentioned this pull request Oct 4, 2022
Merged
@cuviper cuviper removed this from the 1.66.0 milestone Oct 4, 2022
@cuviper cuviper added this to the 1.65.0 milestone Oct 4, 2022
@cuviper cuviper removed the beta-nominated Nominated for backporting to the compiler in the beta channel. label Oct 4, 2022
bors added a commit to rust-lang-ci/rust that referenced this pull request Oct 10, 2022
@bors
Auto merge of rust-lang#102676 - cuviper:beta-next, r=cuviper
da7ffa2 
[beta] backports

* Avoid duplicating StorageLive in let-else rust-lang#101894
* Re-add HRTB implied static bug note rust-lang#101924
* Revert "Copy stage0 binaries into stage0-sysroot" rust-lang#101942
* implied_bounds: deal with inference vars rust-lang#102016
* fix ConstProp handling of written_only_inside_own_block_locals rust-lang#102045
* Fix wrongly refactored Lift impl rust-lang#102088
* Fix a typo “pararmeter” in error message rust-lang#102119
* Deny associated type bindings within associated type bindings rust-lang#102338
* Continue migration of CSS themes rust-lang#101934
* Fix search result colors rust-lang#102369
* Fix unwind drop glue for if-then scopes rust-lang#102394
* Revert "Use getentropy when possible on all Apple platforms" rust-lang#102693
* Fix associated type bindings with anon const in GAT position rust-lang#102336
* Revert perf-regression 101620 rust-lang#102064
* `EscapeAscii` is not an `ExactSizeIterator` rust-lang#99880
@compiler-errors compiler-errors deleted the assoc-ty-binding-in-assoc-ty-binding branch November 2, 2022 02:56
Aaron1011 pushed a commit to Aaron1011/rust that referenced this pull request Jan 6, 2023
@JohnTitor
Rollup merge of rust-lang#102338 - compiler-errors:assoc-ty-binding-i…
b9c8fb0 
…n-assoc-ty-binding, r=cjgillot

Deny associated type bindings within associated type bindings

Fixes rust-lang#102335

This was made worse by rust-lang#100865, which unified the way we generate substs for GATs and non-generic associated types. However, the issue was not _caused_ by rust-lang#100865, evidenced by the test I added for GATs:

```rust
trait T {
    type A: S<C<(), i32 = ()> = ()>;
    //~^ ERROR associated type bindings are not allowed here
}

trait Q {}

trait S {
    type C<T>: Q;
}

fn main() {}
```

^ which passes on beta (where GATs are stable) and presumably ever since GATs support was added to `create_substs_for_associated_item` in astconv.
Aaron1011 pushed a commit to Aaron1011/rust that referenced this pull request Jan 6, 2023
@bors
Auto merge of rust-lang#102388 - JohnTitor:rollup-mbyw6fl, r=JohnTitor
cf62e8a 
Rollup of 8 pull requests

Successful merges:

 - rust-lang#100747 (Add long description and test for E0311)
 - rust-lang#102232 (Stabilize bench_black_box)
 - rust-lang#102288 (Suggest unwrapping `???<T>` if a method cannot be found on it but is present on `T`.)
 - rust-lang#102338 (Deny associated type bindings within associated type bindings)
 - rust-lang#102347 (Unescaping cleanups)
 - rust-lang#102348 (Tweak `FulfillProcessor`.)
 - rust-lang#102378 (Use already resolved `self_ty` in `confirm_fn_pointer_candidate`)
 - rust-lang#102380 (rustdoc: remove redundant mobile `.source > .sidebar` CSS)

Failed merges:

r? `@ghost`
`@rustbot` modify labels: rollup
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Compiler accepts const equality bound involving nonsensical nested equality constraint on associated const
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