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2023-11-04fallback for `construct_generic_bound_failure`bohan-8/+12
2023-11-03Auto merge of #117507 - nnethercote:rustc_span, r=Nilstriebbors-2/+2
`rustc_span` cleanups Just some things I found while looking over this crate. r? `@oli-obk`
2023-11-02Don't check for alias bounds in liveness when aliases have escaping bound varsMichael Goulet-1/+9
2023-11-02Minimize `pub` usage in `source_map.rs`.Nicholas Nethercote-2/+2
Most notably, this commit changes the `pub use crate::*;` in that file to `use crate::*;`. This requires a lot of `use` items in other crates to be adjusted, because everything defined within `rustc_span::*` was also available via `rustc_span::source_map::*`, which is bizarre. The commit also removes `SourceMap::span_to_relative_line_string`, which is unused.
2023-10-29On object safety error, mention new enum as alternativeEsteban Küber-1/+63
When we encounter a `dyn Trait` that isn't object safe, look for its implementors. If there's one, mention using it directly If there are less than 9, mention the possibility of creating a new enum and using that instead. Account for object unsafe `impl Trait on dyn Trait {}`. Make a distinction between public and sealed traits. Fix #80194.
2023-10-29Auto merge of #116733 - compiler-errors:alias-liveness-but-this-time-sound, ↵bors-0/+124
r=aliemjay Consider alias bounds when computing liveness in NLL (but this time sound hopefully) This is a revival of #116040, except removing the changes to opaque lifetime captures check to make sure that we're not triggering any unsoundness due to the lack of general existential regions and the currently-existing `ReErased` hack we use instead. r? `@aliemjay` -- I appreciate you pointing out the unsoundenss in the previous iteration of this PR, and I'd like to hear that you're happy with this iteration of this PR before this goes back into FCP :> Fixes #116794 as well --- (mostly copied from #116040 and reworked slightly) # Background Right now, liveness analysis in NLL is a bit simplistic. It simply walks through all of the regions of a type and marks them as being live at points. This is problematic in the case of aliases, since it requires that we mark **all** of the regions in their args[^1] as live, leading to bugs like #42940. In reality, we may be able to deduce that fewer regions are allowed to be present in the projected type (or "hidden type" for opaques) via item bounds or where clauses, and therefore ideally, we should be able to soundly require fewer regions to be live in the alias. For example: ```rust trait Captures<'a> {} impl<T> Captures<'_> for T {} fn capture<'o>(_: &'o mut ()) -> impl Sized + Captures<'o> + 'static {} fn test_two_mut(mut x: ()) { let _f1 = capture(&mut x); let _f2 = capture(&mut x); //~^ ERROR cannot borrow `x` as mutable more than once at a time } ``` In the example above, we should be able to deduce from the `'static` bound on `capture`'s opaque that even though `'o` is a captured region, it *can never* show up in the opaque's hidden type, and can soundly be ignored for liveness purposes. # The Fix We apply a simple version of RFC 1214's `OutlivesProjectionEnv` and `OutlivesProjectionTraitDef` rules to NLL's `make_all_regions_live` computation. Specifically, when we encounter an alias type, we: 1. Look for a unique outlives bound in the param-env or item bounds for that alias. If there is more than one unique region, bail, unless any of the outlives bound's regions is `'static`, and in that case, prefer `'static`. If we find such a unique region, we can mark that outlives region as live and skip walking through the args of the opaque. 2. Otherwise, walk through the alias's args recursively, as we do today. ## Limitation: Multiple choices This approach has some limitations. Firstly, since liveness doesn't use the same type-test logic as outlives bounds do, we can't really try several options when we're faced with a choice. If we encounter two unique outlives regions in the param-env or bounds, we simply fall back to walking the opaque via its args. I expect this to be mostly mitigated by the special treatment of `'static`, and can be fixed in a forwards-compatible by a more sophisticated analysis in the future. ## Limitation: Opaque hidden types Secondly, we do not employ any of these rules when considering whether the regions captured by a hidden type are valid. That causes this code (cc #42940) to fail: ```rust trait Captures<'a> {} impl<T> Captures<'_> for T {} fn a() -> impl Sized + 'static { b(&vec![]) } fn b<'o>(_: &'o Vec<i32>) -> impl Sized + Captures<'o> + 'static {} ``` We need to have existential regions to avoid [unsoundness](https://github.com/rust-lang/rust/pull/116040#issuecomment-1751628189) when an opaque captures a region which is not represented in its own substs but which outlives a region that does. ## Read more Context: https://github.com/rust-lang/rust/pull/115822#issuecomment-1731153952 (for the liveness case) More context: https://github.com/rust-lang/rust/issues/42940#issuecomment-455198309 (for the opaque capture case, which this does not fix) [^1]: except for bivariant region args in opaques, which will become less relevant when we move onto edition 2024 capture semantics for opaques.
2023-10-27Account for type param from other item in `note_and_explain`Esteban Küber-43/+61
Fix #89868.
2023-10-26Restrict param constraint suggestionEsteban Küber-4/+7
When encountering an associated item with a type param that could be constrained, do not look at the parent item if the type param comes from the associated item. Fix #117209.
2023-10-25Refactor away the need for some `descr` methods.Oli Scherer-10/+11
Instead we use `Display` impls and their `alternate` render scheme to decide whether we want backticks or not.
2023-10-24Get rid of 'tcx on ConstVid, EffectVidMichael Goulet-66/+78
2023-10-24Rollup merge of #117091 - compiler-errors:debug, r=lcnrMatthias Krüger-1/+3
`OptWithInfcx` naming nits, trait bound simplifications * Use an associated type `Interner` on `InferCtxtLike` to remove a redundant interner parameter (`I: Interner, Infcx: InferCtxtLike<I>` -> `Infcx: InferCtxtLike`). * Remove double-`Option` between `infcx: Option<Infcx>` and `fn universe_of_ty(&self, ty: ty::InferTy) -> Option<ty::UniverseIndex>`. We don't need the infcx to be optional if we can provide a "noop" (`NoInfcx`) implementation that just always returns `None` for universe index. * Also removes the `core::convert::Infallible` implementation which I found a bit weird... * Some naming nits with params. * I found `InferCtxt` + `InfCtx` and `Infcx` to be a lot of different ways to spell "inference context", so I got rid of the `InfCtx` type parameter name in favor of `Infcx` which is a more standard name. * I found `OptWithInfcx` to be a bit redundant -> `WithInfcx`. I'm making these changes because I intend to reuse the `InferCtxtLike` trait for uplifting the canonicalizer into a new trait -- conveniently, the information I need for uplifting the canonicalizer also is just the universe information of a type var, so it's super convenient 😸 r? `@BoxyUwU` or `@lcnr`
2023-10-23Auto merge of #117103 - matthiaskrgr:rollup-96zuuom, r=matthiaskrgrbors-41/+51
Rollup of 6 pull requests Successful merges: - #107159 (rand use getrandom for freebsd (available since 12.x)) - #116859 (Make `ty::print::Printer` take `&mut self` instead of `self`) - #117046 (return unfixed len if pat has reported error) - #117070 (rustdoc: wrap Type with Box instead of Generics) - #117074 (Remove smir from triage and add me to stablemir) - #117086 (Update .mailmap to promote my livename) r? `@ghost` `@rustbot` modify labels: rollup
2023-10-23Rollup merge of #116859 - Nilstrieb:more-more-funny-pretty-printers, r=oli-obkMatthias Krüger-41/+51
Make `ty::print::Printer` take `&mut self` instead of `self` based on #116815 This simplifies the code by removing all the `self` assignments and makes the flow of data clearer - always into the printer. Especially in v0 mangling, which already used `&mut self` in some places, it gets a lot more uniform.
2023-10-23Remove redundant type parameterMichael Goulet-1/+3
2023-10-22use visibility to check unused imports and delete some stmtsbohan-1/+0
2023-10-21Rollup merge of #106601 - estebank:match-semi, r=cjgillotMatthias Krüger-0/+13
Suggest `;` after bare `match` expression E0308 Fix #72634.
2023-10-21Make `ty::print::Printer` take `&mut self` instead of `self`Nilstrieb-41/+51
This simplifies the code by removing all the `self` assignments and makes the flow of data clearer - always into the printer. Especially in v0 mangling, which already used `&mut self` in some places, it gets a lot more uniform.
2023-10-20s/generator/coroutine/Oli Scherer-11/+11
2023-10-20s/Generator/Coroutine/Oli Scherer-11/+11
2023-10-19Auto merge of #116874 - compiler-errors:elaborator-nits, r=wesleywiserbors-34/+29
Some small elaborator nits Didn't want to fold these into a totally unrelated pr.
2023-10-19Rollup merge of #116908 - estebank:issue-78206, r=compiler-errorsLeón Orell Valerian Liehr-4/+19
Tweak wording of type errors involving type params Fix #78206.
2023-10-18Tweak wording of type errors involving type paramsEsteban Küber-4/+19
Fix #78206.
2023-10-18Don't ICE when encountering unresolved regions in fully_resolveMichael Goulet-7/+20
2023-10-18Auto merge of #116885 - aliemjay:rollup-plbeppt, r=aliemjaybors-63/+59
Rollup of 5 pull requests Successful merges: - #116812 (Disable missing_copy_implementations lint on non_exhaustive types) - #116856 (Disable effects in libcore again) - #116865 (Suggest constraining assoc types in more cases) - #116870 (Don't compare host param by name) - #116879 (revert #114586) r? `@ghost` `@rustbot` modify labels: rollup
2023-10-18Rollup merge of #116879 - aliemjay:revert-opaque-bubble, r=oli-obkAli MJ Al-Nasrawy-19/+1
revert #114586 Reverts #114586. cc #116877 (not closing until this gets a beta backport) fixes #116684 fixes https://github.com/rust-lang/rust/pull/114586#issuecomment-1751967321 r? `@oli-obk` or `@lcnr`
2023-10-18revert rust-lang/rust#114586Ali MJ Al-Nasrawy-19/+1
2023-10-18Make sure that non-pretty-printing usages are using the correct elaboratorMichael Goulet-2/+2
2023-10-18Simplify transitive_bounds_that_define_assoc_itemMichael Goulet-33/+28
2023-10-17Suggest constraining assoc types in more casesEsteban Küber-44/+58
Fix #46969.
2023-10-17Remove `Print::Error`Nilstrieb-2/+2
All printing goes through `fmt::Error` now.
2023-10-17Remove `Printer::Error`Nilstrieb-24/+20
It's always a `fmt::Error` except in some cases where it was `!`, but we're not really winning anything in that case.
2023-10-17Remove `Print::Output`Nilstrieb-2/+2
Now that `Printer` doesn't have subprinters anymore, the output of a printing operation is always the same.
2023-10-17Remove "subprinter" types from `Printer`Nilstrieb-25/+24
These are `Self` in almost all printers except one, which can just store the state as a field instead. This simplifies the printer and allows for further simplifications, for example using `&mut self` instead of passing around the printer.
2023-10-17Use a visitor that could be reused by opaque type capture check laterMichael Goulet-0/+124
2023-10-13Format all the let chains in compilerMichael Goulet-168/+252
2023-10-11Suggest `;` after bare `match` expression E0308Esteban Küber-0/+13
Fix #72634.
2023-10-11Rollup merge of #116219 - compiler-errors:relate-alias-ty-with-variance, r=lcnrMatthias Krüger-2/+2
Relate alias ty with variance In the new solver, turns out that the subst-relate branch of the alias-relate predicate was relating args invariantly even for opaques, which have variance :skull:. This change is a bit more invasive, but I'd rather not special-case it [here](https://github.com/rust-lang/rust/blob/aeaa5c30e5c9041264a2e8314b68ad84c2dc3169/compiler/rustc_trait_selection/src/solve/alias_relate.rs#L171-L190) and then have it break elsewhere. I'm doing a perf run to see if the extra call to `def_kind` is that expensive, if it is, I'll reconsider. r? ``@lcnr``
2023-10-11Auto merge of #115948 - notriddle:notriddle/logo-lockup, r=fmeasebors-0/+3
rustdoc: show crate name beside smaller logo *Blocked on https://github.com/rust-lang/cargo/pull/12800* ## Summary In this PR, the crate name and version are always shown in the sidebar, even in subpages, and the lateral navigation is always shown in the sidebar, even in modules. Clicking the crate name does the same thing clicking the logo always did: take you to the crate root (the crate's home page, at least within Rustdoc). The Rust logo is also no longer shown by default for non-Rust docs. ### Screenshots <details><summary>Before</summary> | | Macro | Module | |--|-------|--------| | In crate | ![image](https://github.com/rust-lang/rust/assets/1593513/d5db0a46-2bb6-44a2-a3aa-2d915ecb8595) |![image](https://github.com/rust-lang/rust/assets/1593513/61f8c1ee-c298-4e2c-b791-18ecb79ab83b) | In module[^1] | ![image](https://github.com/rust-lang/rust/assets/1593513/73abca59-0b69-4650-a1e2-7278ca34795c) | ![image](https://github.com/rust-lang/rust/assets/1593513/0baf02c2-2ec7-4674-80e5-a6a74a973376) [^1]: This PR also includes a bug fix for derive macros not showing up in the lateral navigation part of the sidebar </details> #### Whole sidebar screenshots | | Macro | Module | |--|-------|--------| | In crate | ![image](https://github.com/rust-lang/rust/assets/1593513/75d1bd07-41f7-4f11-ba24-fd5476e0586a) | ![image](https://github.com/rust-lang/rust/assets/1593513/52960259-2b65-4131-b380-01826f0a0eb7) | In module | ![image](https://github.com/rust-lang/rust/assets/1593513/06e57928-8cb0-41bd-b152-be16cc53e5ec) | ![image](https://github.com/rust-lang/rust/assets/1593513/37291c69-2a07-4467-a382-d9b029084a47) #### Different logo configurations | | Short crate name | Long crate name | |---------|------------------|-----------------| | Root | ![short-root] | ![long-root] | Subpage | ![short-subpage] | ![long-subpage] [short-root]: https://github.com/rust-lang/rust/assets/1593513/9e2b4fa8-f581-4106-b562-1e0372c13f79 [short-subpage]: https://github.com/rust-lang/rust/assets/1593513/8331cdb8-fa13-4671-a1e2-dcc1cdca7451 [long-root]: https://github.com/rust-lang/rust/assets/1593513/7d377fec-0f1d-4343-9f82-0e35a8f58056 [long-subpage]: https://github.com/rust-lang/rust/assets/1593513/3b3094a4-63c9-477c-8c15-b6075837df30 ##### Without a logo ![image](https://github.com/rust-lang/rust/assets/1593513/66672b79-6c59-4be8-a527-25ef6f0b04ab) ### Preview pages https://notriddle.com/rustdoc-html-demo-5/sidebar-layout-rocket/rocket/index.html https://notriddle.com/rustdoc-html-demo-5/sidebar-layout-rocket/rocket_sync_db_pools/index.html https://notriddle.com/rustdoc-html-demo-5/sidebar-layout-rust-compiler/index.html https://notriddle.com/rustdoc-html-demo-5/sidebar-layout-rust/std/index.html https://notriddle.com/rustdoc-html-demo-5/sidebar-layout-rocket/tokio/index.html ## Motivation This improves visual information density (the construct with the logo and crate name is *shorter* than the logo on its own, because it's not square) and navigation clarity (we can now see what clicking the Rust logo does, specifically). Compare this with the layout at [Phoenix's Hexdocs] (which is what this proposal is closely based on), the old proposal on [Internals Discourse] (which always says "Rust standard library" in the sidebar, but doesn't do the side-by-side layout). [Phoenix's Hexdocs]: https://hexdocs.pm/phoenix/1.7.7/overview.html [Internals Discourse]: https://internals.rust-lang.org/t/poc-of-a-new-design-for-the-generated-rustdoc/11018 ## Guide-level explanation This PR cleans up some of the sidebar navigation. It makes the logo in the desktop sidebar a bit smaller, and puts the crate name and version next to it (either beside it, or below it, depending on if there's space), making it clearer what clicking on it does: click the crate name to open the crate's home page. It also removes the Rust logo from non-official-Rust crates, again to make the navigation and supply chain clearer (since the crate name has been added, the logo is no longer necessary for navigation). It adds a bit more clarifying information for lateral navigation. On items that don't add their own sidebar items, it just shows its siblings directly below the crate name and logo, but for other items, it shows "In crate alloc" instead of just "In alloc". It also shows the lateral navigation tools on module pages, making modules consistent with every other item. ## Drawbacks While this actually takes up less screen real estate than the old layout on desktop, it takes up more HTML. It's also a bit more visually complex. ## Rationale and alternatives I could do what the Internals POC did and keep the vertically stacked layout all the time, instead of doing a horizontal stack where possible. It would take up more screen real estate, though. ## Prior art This design is lifted almost verbatim from Hexdocs. It seems to work for them. [`opentelemetry_process_propagator`], for example, has a long application name. [`opentelemetry_process_propagator`]: https://hexdocs.pm/opentelemetry_process_propagator/OpentelemetryProcessPropagator.html ## Unresolved questions Maybe we should encourage crate authors to include their own logo more often? It certainly helps give people a better sense of "place." This seems to be blocked on coming up with an API to do it without requiring them to host the file somewhere. ## Future possibilities Beyond this, plenty of other changes could be made to improve the layout, like * Fix things so that clicking an item in the sidebar doesn't cause it to scroll back to the top. * The [Internals demo](https://utherii.github.io/new.html) does this right: clicking an item in the sidebar changes the content area, but the sidebar itself does not change. This is nice, because clicking is cheap and I can skim the opening few paragraphs while browsing. * The layout of the docs sidebar causes trouble to implement this, because it's different on different pages, but at least fix this on the file browser. * Come up with a less cluttered way to do disclosure. There's a lot of `[-]` on the page. * We don't lack ideas to fix this one. We have *too many*. * Do a better job of separating local navigation (vec::Vec links to vec::IntoIter) and the table of contents (vec::Vec links to vec::Vec::new). * A possibility: add a Back arrow next to the "In [module]" header? ![image](https://github.com/rust-lang/rust/assets/1593513/e969faf7-7722-457a-b8c6-8d962e9e1e23) * Give readers more control of how much rustdoc shows them, and giving doc authors more control of how much it generates. Basically, https://github.com/rust-lang/rust/pull/115660 is great, let's do it too. But those are mostly orthogonal, not future possibilities unlocked by this change.
2023-10-08rustdoc: remove rust logo from non-Rust cratesMichael Howell-0/+3
2023-10-08remove trailing dotsAli MJ Al-Nasrawy-1/+1
2023-10-08always show and explain sub regionAli MJ Al-Nasrawy-37/+23
2023-10-08improve the suggestion of generic_bound_failureAli MJ Al-Nasrawy-299/+201
2023-10-06Auto merge of #114811 - estebank:impl-ambiguity, r=wesleywiserbors-1/+1
Show more information when multiple `impl`s apply - When there are `impl`s without type params, show only those (to avoid showing overly generic `impl`s). ``` error[E0283]: type annotations needed --> $DIR/multiple-impl-apply.rs:34:9 | LL | let y = x.into(); | ^ ---- type must be known at this point | note: multiple `impl`s satisfying `_: From<Baz>` found --> $DIR/multiple-impl-apply.rs:14:1 | LL | impl From<Baz> for Bar { | ^^^^^^^^^^^^^^^^^^^^^^ ... LL | impl From<Baz> for Foo { | ^^^^^^^^^^^^^^^^^^^^^^ = note: required for `Baz` to implement `Into<_>` help: consider giving `y` an explicit type | LL | let y: /* Type */ = x.into(); | ++++++++++++ ``` - Lower the importance of `T: Sized`, `T: WellFormed` and coercion errors, to prioritize more relevant errors. The pre-existing deduplication logic deals with hiding redundant errors better that way, and we show errors with more metadata that is useful to the user. - Show `<SelfTy as Trait>::assoc_fn` suggestion in more cases. ``` error[E0790]: cannot call associated function on trait without specifying the corresponding `impl` type --> $DIR/cross-return-site-inference.rs:38:16 | LL | return Err(From::from("foo")); | ^^^^^^^^^^ cannot call associated function of trait | help: use a fully-qualified path to a specific available implementation | LL | return Err(</* self type */ as From>::from("foo")); | +++++++++++++++++++ + ``` Fix #88284.
2023-10-04Point to where missing return type should goMichael Goulet-5/+5
2023-10-04Make it clear that args default to being related invariantlyMichael Goulet-2/+2
2023-10-04Show suggestion for `<SelfTy as Trait>::assoc_fn` in more cases and fmt codeEsteban Küber-1/+1
2023-10-02Rename both of the Match relationsMichael Goulet-8/+16
2023-09-27fix clippy::{redundant_guards, useless_format}Matthias Krüger-1/+1
2023-09-26Don't store lazyness in DefKindMichael Goulet-2/+2
2023-09-24Remove span from BrAnon.Camille GILLOT-21/+9