don't suggest unsized indirection in where-clauses #85979
Merged
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Skip where-clauses when suggesting using indirection in combination with `?Sized` bounds on type parameters.
|
r? @davidtwco (rust-highfive has picked a reviewer for you, use r? to override) |
rust-highfive
added
the
S-waiting-on-review
|
📌 Commit e848be0 has been approved by |
bors
added
S-waiting-on-bors
bors
added a commit
to rust-lang-ci/rust
that referenced
this pull request
Jun 4, 2021
Rollup of 10 pull requests Successful merges: - rust-lang#83653 (Remove unused code from `rustc_data_structures::sync`) - rust-lang#84466 (rustdoc: Remove `PrimitiveType::{to_url_str, as_str}`) - rust-lang#84880 (Make match in `register_res` easier to read) - rust-lang#84942 (rustdoc: link to stable/beta docs consistently in documentation) - rust-lang#85853 (Warn against boxed DST in `improper_ctypes_definitions` lint) - rust-lang#85939 (Fix suggestion for removing &mut from &mut macro!().) - rust-lang#85966 (wasm: Make simd types passed via indirection again) - rust-lang#85979 (don't suggest unsized indirection in where-clauses) - rust-lang#85983 (Update to semver 1.0.3) - rust-lang#85988 (Note that `ninja = false` goes under `[llvm]`) Failed merges: r? `@ghost` `@rustbot` modify labels: rollup
JohnTitor
added a commit
to JohnTitor/rust
that referenced
this pull request
Oct 15, 2021
…stebank move implicit `Sized` predicate to end of list In `Bounds::predicates()`, move the implicit `Sized` predicate to the end of the generated list. This means that if there is an explicit `Sized` bound, it will be checked first, and any resulting diagnostics will have a more useful span. Fixes rust-lang#85998, at least partially. ~~Based on rust-lang#85979, but only the last 2 commits are new for this pull request.~~ (edit: rebased) A full fix would need to deal with where-clauses, and that seems difficult. Basically, predicates are being collected in multiple stages, and there are two places where implicit `Sized` predicates can be inserted: once for generic parameters, and once for where-clauses. I think this insertion is happening too early, and we should actually do it only at points where we collect all of the relevant trait bounds for a type parameter. I could use some help interpreting the changes to the stderr output. It looks like reordering the predicates changed some diagnostics that don't obviously have anything to do with `Sized` bounds. Possibly some error reporting code is making assumptions about ordering of predicates? The diagnostics for src/test/ui/derives/derives-span-Hash-*.rs seem to have improved, no longer pointing at the type parameter identifier, but src/test/ui/type-alias-impl-trait/generic_duplicate_param_use9.rs became less verbose for some reason. I also ran into an instance of rust-lang#84970 while working on this, but I kind of expected that could happen, because I'm reordering predicates. I can open a separate issue on that if it would be helpful. `@estebank` this seems likely to conflict (slightly?) with your work on rust-lang#85947; how would you like to resolve that?
matthiaskrgr
added a commit
to matthiaskrgr/rust
that referenced
this pull request
Oct 15, 2021
…stebank move implicit `Sized` predicate to end of list In `Bounds::predicates()`, move the implicit `Sized` predicate to the end of the generated list. This means that if there is an explicit `Sized` bound, it will be checked first, and any resulting diagnostics will have a more useful span. Fixes rust-lang#85998, at least partially. ~~Based on rust-lang#85979, but only the last 2 commits are new for this pull request.~~ (edit: rebased) A full fix would need to deal with where-clauses, and that seems difficult. Basically, predicates are being collected in multiple stages, and there are two places where implicit `Sized` predicates can be inserted: once for generic parameters, and once for where-clauses. I think this insertion is happening too early, and we should actually do it only at points where we collect all of the relevant trait bounds for a type parameter. I could use some help interpreting the changes to the stderr output. It looks like reordering the predicates changed some diagnostics that don't obviously have anything to do with `Sized` bounds. Possibly some error reporting code is making assumptions about ordering of predicates? The diagnostics for src/test/ui/derives/derives-span-Hash-*.rs seem to have improved, no longer pointing at the type parameter identifier, but src/test/ui/type-alias-impl-trait/generic_duplicate_param_use9.rs became less verbose for some reason. I also ran into an instance of rust-lang#84970 while working on this, but I kind of expected that could happen, because I'm reordering predicates. I can open a separate issue on that if it would be helpful. ``@estebank`` this seems likely to conflict (slightly?) with your work on rust-lang#85947; how would you like to resolve that?
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Skip where-clauses when suggesting using indirection in combination with
?Sizedbounds on type parameters.Fixes #85943.
@estebank I think this doesn't conflict with your work in #85947; please let me know if you'd like me to cherry pick it to a new branch based on yours instead.