Provide more context on recursive `impl` evaluation overflow by estebank · Pull Request #119389 · rust-lang/rust

estebank · 2023-12-28T19:09:16Z

When an associated type Self::Assoc is part of a where clause, we end up unable to evaluate the requirement and emit a E0275.

We now point at the associated type if specified in the impl. If so, we also suggest using that type instead of Self::Assoc. Otherwise, we explain that these are not allowed.

error[E0275]: overflow evaluating the requirement `<(T,) as Grault>::A == _`
  --> $DIR/impl-wf-cycle-1.rs:15:1
   |
LL | / impl<T: Grault> Grault for (T,)
LL | |
LL | | where
LL | |     Self::A: Baz,
LL | |     Self::B: Fiz,
   | |_________________^
LL |   {
LL |       type A = ();
   |       ------ associated type `<(T,) as Grault>::A` is specified here
   |
note: required for `(T,)` to implement `Grault`
  --> $DIR/impl-wf-cycle-1.rs:15:17
   |
LL | impl<T: Grault> Grault for (T,)
   |                 ^^^^^^     ^^^^
...
LL |     Self::A: Baz,
   |              --- unsatisfied trait bound introduced here
   = note: 1 redundant requirement hidden
   = note: required for `(T,)` to implement `Grault`
help: associated type for the current `impl` cannot be restricted in `where` clauses, remove this bound
   |
LL -     Self::A: Baz,
   |

error[E0275]: overflow evaluating the requirement `<T as B>::Type == <T as B>::Type`
  --> $DIR/impl-wf-cycle-3.rs:7:1
   |
LL | / impl<T> B for T
LL | | where
LL | |     T: A<Self::Type>,
   | |_____________________^
LL |   {
LL |       type Type = bool;
   |       --------- associated type `<T as B>::Type` is specified here
   |
note: required for `T` to implement `B`
  --> $DIR/impl-wf-cycle-3.rs:7:9
   |
LL | impl<T> B for T
   |         ^     ^
LL | where
LL |     T: A<Self::Type>,
   |        ------------- unsatisfied trait bound introduced here
help: replace the associated type with the type specified in this `impl`
   |
LL |     T: A<bool>,
   |          ~~~~

error[E0275]: overflow evaluating the requirement `<T as Filter>::ToMatch == <T as Filter>::ToMatch`
  --> $DIR/impl-wf-cycle-4.rs:5:1
   |
LL | / impl<T> Filter for T
LL | | where
LL | |     T: Fn(Self::ToMatch),
   | |_________________________^
   |
note: required for `T` to implement `Filter`
  --> $DIR/impl-wf-cycle-4.rs:5:9
   |
LL | impl<T> Filter for T
   |         ^^^^^^     ^
LL | where
LL |     T: Fn(Self::ToMatch),
   |        ----------------- unsatisfied trait bound introduced here
note: associated types for the current `impl` cannot be restricted in `where` clauses
  --> $DIR/impl-wf-cycle-4.rs:7:11
   |
LL |     T: Fn(Self::ToMatch),
   |           ^^^^^^^^^^^^^

Fix #116925

rustbot · 2023-12-28T19:09:25Z

r? @petrochenkov

(rustbot has picked a reviewer for you, use r? to override)

bors · 2023-12-28T23:49:01Z

☔ The latest upstream changes (presumably #119174) made this pull request unmergeable. Please resolve the merge conflicts.

petrochenkov · 2023-12-29T00:14:30Z

r? compiler
I'm overloaded with reviews.

bors · 2024-01-05T19:29:59Z

☔ The latest upstream changes (presumably #119621) made this pull request unmergeable. Please resolve the merge conflicts.

TaKO8Ki

I left some suggestions. Other than them, r=me

compiler/rustc_trait_selection/src/traits/error_reporting/suggestions.rs

TaKO8Ki · 2024-01-12T04:36:37Z

@rustbot author

When an associated type `Self::Assoc` is part of a `where` clause, we end up unable to evaluate the requirement and emit a E0275. We now point at the associated type if specified in the `impl`. If so, we also suggest using that type instead of `Self::Assoc`. Otherwise, we explain that these are not allowed. ``` error[E0275]: overflow evaluating the requirement `<(T,) as Grault>::A == _` --> $DIR/impl-wf-cycle-1.rs:15:1 | LL | / impl<T: Grault> Grault for (T,) LL | | LL | | where LL | | Self::A: Baz, LL | | Self::B: Fiz, | |_________________^ LL | { LL | type A = (); | ------ associated type `<(T,) as Grault>::A` is specified here | note: required for `(T,)` to implement `Grault` --> $DIR/impl-wf-cycle-1.rs:15:17 | LL | impl<T: Grault> Grault for (T,) | ^^^^^^ ^^^^ ... LL | Self::A: Baz, | --- unsatisfied trait bound introduced here = note: 1 redundant requirement hidden = note: required for `(T,)` to implement `Grault` help: associated type for the current `impl` cannot be restricted in `where` clauses, remove this bound | LL - Self::A: Baz, LL + , | ``` ``` error[E0275]: overflow evaluating the requirement `<T as B>::Type == <T as B>::Type` --> $DIR/impl-wf-cycle-3.rs:7:1 | LL | / impl<T> B for T LL | | where LL | | T: A<Self::Type>, | |_____________________^ LL | { LL | type Type = bool; | --------- associated type `<T as B>::Type` is specified here | note: required for `T` to implement `B` --> $DIR/impl-wf-cycle-3.rs:7:9 | LL | impl<T> B for T | ^ ^ LL | where LL | T: A<Self::Type>, | ------------- unsatisfied trait bound introduced here help: replace the associated type with the type specified in this `impl` | LL | T: A<bool>, | ~~~~ ``` ``` error[E0275]: overflow evaluating the requirement `<T as Filter>::ToMatch == <T as Filter>::ToMatch` --> $DIR/impl-wf-cycle-4.rs:5:1 | LL | / impl<T> Filter for T LL | | where LL | | T: Fn(Self::ToMatch), | |_________________________^ | note: required for `T` to implement `Filter` --> $DIR/impl-wf-cycle-4.rs:5:9 | LL | impl<T> Filter for T | ^^^^^^ ^ LL | where LL | T: Fn(Self::ToMatch), | ----------------- unsatisfied trait bound introduced here note: associated types for the current `impl` cannot be restricted in `where` clauses --> $DIR/impl-wf-cycle-4.rs:7:11 | LL | T: Fn(Self::ToMatch), | ^^^^^^^^^^^^^ ``` Fix rust-lang#116925

estebank · 2024-01-22T17:53:13Z

@rustbot review

TaKO8Ki · 2024-01-24T06:38:20Z

@bors r+ rollup

bors · 2024-01-24T06:38:22Z

📌 Commit 29bdf9e has been approved by TaKO8Ki

It is now in the queue for this repository.

Provide more context on recursive `impl` evaluation overflow When an associated type `Self::Assoc` is part of a `where` clause, we end up unable to evaluate the requirement and emit a E0275. We now point at the associated type if specified in the `impl`. If so, we also suggest using that type instead of `Self::Assoc`. Otherwise, we explain that these are not allowed. ``` error[E0275]: overflow evaluating the requirement `<(T,) as Grault>::A == _` --> $DIR/impl-wf-cycle-1.rs:15:1 | LL | / impl<T: Grault> Grault for (T,) LL | | LL | | where LL | | Self::A: Baz, LL | | Self::B: Fiz, | |_________________^ LL | { LL | type A = (); | ------ associated type `<(T,) as Grault>::A` is specified here | note: required for `(T,)` to implement `Grault` --> $DIR/impl-wf-cycle-1.rs:15:17 | LL | impl<T: Grault> Grault for (T,) | ^^^^^^ ^^^^ ... LL | Self::A: Baz, | --- unsatisfied trait bound introduced here = note: 1 redundant requirement hidden = note: required for `(T,)` to implement `Grault` help: associated type for the current `impl` cannot be restricted in `where` clauses, remove this bound | LL - Self::A: Baz, | ``` ``` error[E0275]: overflow evaluating the requirement `<T as B>::Type == <T as B>::Type` --> $DIR/impl-wf-cycle-3.rs:7:1 | LL | / impl<T> B for T LL | | where LL | | T: A<Self::Type>, | |_____________________^ LL | { LL | type Type = bool; | --------- associated type `<T as B>::Type` is specified here | note: required for `T` to implement `B` --> $DIR/impl-wf-cycle-3.rs:7:9 | LL | impl<T> B for T | ^ ^ LL | where LL | T: A<Self::Type>, | ------------- unsatisfied trait bound introduced here help: replace the associated type with the type specified in this `impl` | LL | T: A<bool>, | ~~~~ ``` ``` error[E0275]: overflow evaluating the requirement `<T as Filter>::ToMatch == <T as Filter>::ToMatch` --> $DIR/impl-wf-cycle-4.rs:5:1 | LL | / impl<T> Filter for T LL | | where LL | | T: Fn(Self::ToMatch), | |_________________________^ | note: required for `T` to implement `Filter` --> $DIR/impl-wf-cycle-4.rs:5:9 | LL | impl<T> Filter for T | ^^^^^^ ^ LL | where LL | T: Fn(Self::ToMatch), | ----------------- unsatisfied trait bound introduced here note: associated types for the current `impl` cannot be restricted in `where` clauses --> $DIR/impl-wf-cycle-4.rs:7:11 | LL | T: Fn(Self::ToMatch), | ^^^^^^^^^^^^^ ``` Fix rust-lang#116925

Rollup of 8 pull requests Successful merges: - rust-lang#119305 (Add `AsyncFn` family of traits) - rust-lang#119389 (Provide more context on recursive `impl` evaluation overflow) - rust-lang#120062 (llvm: change data layout bug to an error and make it trigger more) - rust-lang#120099 (linker: Refactor library linking methods in `trait Linker`) - rust-lang#120201 (Bump some deps with syn 1.0 dependencies) - rust-lang#120230 (Assert that a single scope is passed to `for_scope`) - rust-lang#120278 (Remove --fatal-warnings on wasm targets) - rust-lang#120292 (coverage: Dismantle `Instrumentor` and flatten span refinement) r? `@ghost` `@rustbot` modify labels: rollup

…iaskrgr Rollup of 10 pull requests Successful merges: - rust-lang#119305 (Add `AsyncFn` family of traits) - rust-lang#119389 (Provide more context on recursive `impl` evaluation overflow) - rust-lang#119895 (Remove `track_errors` entirely) - rust-lang#120230 (Assert that a single scope is passed to `for_scope`) - rust-lang#120278 (Remove --fatal-warnings on wasm targets) - rust-lang#120292 (coverage: Dismantle `Instrumentor` and flatten span refinement) - rust-lang#120315 (On E0308 involving `dyn Trait`, mention trait objects) - rust-lang#120317 (pattern_analysis: Let `ctor_sub_tys` return any Iterator they want) - rust-lang#120318 (pattern_analysis: Reuse most of the `DeconstructedPat` `Debug` impl) - rust-lang#120325 (rustc_data_structures: use either instead of itertools) r? `@ghost` `@rustbot` modify labels: rollup

Rollup merge of rust-lang#119389 - estebank:issue-116925, r=TaKO8Ki Provide more context on recursive `impl` evaluation overflow When an associated type `Self::Assoc` is part of a `where` clause, we end up unable to evaluate the requirement and emit a E0275. We now point at the associated type if specified in the `impl`. If so, we also suggest using that type instead of `Self::Assoc`. Otherwise, we explain that these are not allowed. ``` error[E0275]: overflow evaluating the requirement `<(T,) as Grault>::A == _` --> $DIR/impl-wf-cycle-1.rs:15:1 | LL | / impl<T: Grault> Grault for (T,) LL | | LL | | where LL | | Self::A: Baz, LL | | Self::B: Fiz, | |_________________^ LL | { LL | type A = (); | ------ associated type `<(T,) as Grault>::A` is specified here | note: required for `(T,)` to implement `Grault` --> $DIR/impl-wf-cycle-1.rs:15:17 | LL | impl<T: Grault> Grault for (T,) | ^^^^^^ ^^^^ ... LL | Self::A: Baz, | --- unsatisfied trait bound introduced here = note: 1 redundant requirement hidden = note: required for `(T,)` to implement `Grault` help: associated type for the current `impl` cannot be restricted in `where` clauses, remove this bound | LL - Self::A: Baz, | ``` ``` error[E0275]: overflow evaluating the requirement `<T as B>::Type == <T as B>::Type` --> $DIR/impl-wf-cycle-3.rs:7:1 | LL | / impl<T> B for T LL | | where LL | | T: A<Self::Type>, | |_____________________^ LL | { LL | type Type = bool; | --------- associated type `<T as B>::Type` is specified here | note: required for `T` to implement `B` --> $DIR/impl-wf-cycle-3.rs:7:9 | LL | impl<T> B for T | ^ ^ LL | where LL | T: A<Self::Type>, | ------------- unsatisfied trait bound introduced here help: replace the associated type with the type specified in this `impl` | LL | T: A<bool>, | ~~~~ ``` ``` error[E0275]: overflow evaluating the requirement `<T as Filter>::ToMatch == <T as Filter>::ToMatch` --> $DIR/impl-wf-cycle-4.rs:5:1 | LL | / impl<T> Filter for T LL | | where LL | | T: Fn(Self::ToMatch), | |_________________________^ | note: required for `T` to implement `Filter` --> $DIR/impl-wf-cycle-4.rs:5:9 | LL | impl<T> Filter for T | ^^^^^^ ^ LL | where LL | T: Fn(Self::ToMatch), | ----------------- unsatisfied trait bound introduced here note: associated types for the current `impl` cannot be restricted in `where` clauses --> $DIR/impl-wf-cycle-4.rs:7:11 | LL | T: Fn(Self::ToMatch), | ^^^^^^^^^^^^^ ``` Fix rust-lang#116925

rustbot assigned petrochenkov Dec 28, 2023

rustbot added S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. T-compiler Relevant to the compiler team, which will review and decide on the PR/issue. labels Dec 28, 2023

estebank force-pushed the issue-116925 branch from bcc56ac to e1381ba Compare December 28, 2023 19:10

rustbot assigned TaKO8Ki and unassigned petrochenkov Dec 29, 2023

estebank force-pushed the issue-116925 branch from 1b953a7 to 48bcad6 Compare January 4, 2024 00:21

estebank force-pushed the issue-116925 branch from be7148f to 18caf3b Compare January 8, 2024 23:08

TaKO8Ki reviewed Jan 9, 2024

View reviewed changes

compiler/rustc_trait_selection/src/traits/error_reporting/suggestions.rs Outdated Show resolved Hide resolved

compiler/rustc_trait_selection/src/traits/error_reporting/suggestions.rs Outdated Show resolved Hide resolved

rustbot added S-waiting-on-author Status: This is awaiting some action (such as code changes or more information) from the author. and removed S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. labels Jan 12, 2024

estebank added 3 commits January 19, 2024 23:55

Account for trailing comma in removal suggestion

c85bb27

Account for single where bound being removed

29bdf9e

estebank force-pushed the issue-116925 branch from 18caf3b to 29bdf9e Compare January 22, 2024 17:52

rustbot added S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. and removed S-waiting-on-author Status: This is awaiting some action (such as code changes or more information) from the author. labels Jan 22, 2024

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 Jan 24, 2024

fmease mentioned this pull request Jan 24, 2024

Rollup of 8 pull requests #120304

Closed

matthiaskrgr mentioned this pull request Jan 25, 2024

Rollup of 10 pull requests #120335

Merged

bors merged commit fd92d88 into rust-lang:master Jan 25, 2024

rustbot added this to the 1.77.0 milestone Jan 25, 2024

Provide feedback

Saved searches

Use saved searches to filter your results more quickly

Uh oh!

Provide more context on recursive `impl` evaluation overflow#119389

Provide more context on recursive `impl` evaluation overflow#119389
bors merged 3 commits intorust-lang:masterfrom
estebank:issue-116925

estebank commented Dec 28, 2023 •

edited

Loading

Uh oh!

rustbot commented Dec 28, 2023

Uh oh!

bors commented Dec 28, 2023

Uh oh!

petrochenkov commented Dec 29, 2023

Uh oh!

bors commented Jan 5, 2024

Uh oh!

TaKO8Ki left a comment

Uh oh!

Uh oh!

Uh oh!

TaKO8Ki commented Jan 12, 2024

Uh oh!

estebank commented Jan 22, 2024

Uh oh!

TaKO8Ki commented Jan 24, 2024

Uh oh!

bors commented Jan 24, 2024

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

5 participants

Uh oh!

Conversation

estebank commented Dec 28, 2023 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Uh oh!

rustbot commented Dec 28, 2023

Uh oh!

bors commented Dec 28, 2023

Uh oh!

petrochenkov commented Dec 29, 2023

Uh oh!

bors commented Jan 5, 2024

Uh oh!

TaKO8Ki left a comment

Choose a reason for hiding this comment

Uh oh!

Uh oh!

Uh oh!

TaKO8Ki commented Jan 12, 2024

Uh oh!

estebank commented Jan 22, 2024

Uh oh!

TaKO8Ki commented Jan 24, 2024

Uh oh!

bors commented Jan 24, 2024

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

5 participants

estebank commented Dec 28, 2023 •

edited

Loading