Fix depth check in ProofTreeVisitor.
The hack to cutoff overflows and cycles in the new trait solver was incorrect. We want to inspect everything with depth [0..10].
This fix exposed a previously unseen bug, which caused the compiler to ICE when invoking `trait_ref` on a non-assoc type projection. I simply added the guard in the `AmbiguityCausesVisitor`, and updated the expected output for the `auto-trait-coherence` test which now includes the extra note:
```text
|
= note: upstream crates may add a new impl of trait `std::marker::Send` for type `OpaqueType` in future versions
```
r? `@lcnr`
finish `RegionKind` renaming
second step of https://github.com/rust-lang/types-team/issues/95
continues the work from #117876. While working on this and I encountered a bunch of further cleanup which I'll either open a tracking issue for or will do in a separate PR:
- rewrite the `RegionKind` docs, they still talk about `ReEmpty` and are generally out of date
- rename `DescriptionCtx` to `DescriptionCtxt`
- what is `CheckRegions::Bound`?
- `collect_late_bound_regions` et al
- `erase_late_bound_regions` -> `instantiate_bound_regions_with_erased`?
- `EraseEarlyRegions` visitor should be removed, feels duplicate
r? `@BoxyUwU`
Don't expect a rcvr in `print_disambiguation_help`
We don't necessarily have a receiver when we are both accidentally using the `.` operator *AND* we have more than one ambiguous method candidate.
Fixes#117728
Build pre-coroutine-transform coroutine body on error
I was accidentally building the post-transform coroutine body, rather than the pre-transform coroutine body. There's no pinning expected here yet, and the return type isn't yet transformed into `CoroutineState`.
Fixes#117670
Custom MIR: Support cleanup blocks
Cleanup blocks are declared with `bb (cleanup) = { ... }`.
`Call` and `Drop` terminators take an additional argument describing the unwind action, which is one of the following:
* `UnwindContinue()`
* `UnwindUnreachable()`
* `UnwindTerminate(reason)`, where reason is `ReasonAbi` or `ReasonInCleanup`
* `UnwindCleanup(block)`
Also support unwind resume and unwind terminate terminators:
* `UnwindResume()`
* `UnwindTerminate(reason)`
Cleanup blocks are declared with `bb (cleanup) = { ... }`.
`Call` and `Drop` terminators take an additional argument describing the
unwind action, which is one of the following:
* `UnwindContinue()`
* `UnwindUnreachable()`
* `UnwindTerminate(reason)`, where reason is `ReasonAbi` or `ReasonInCleanup`
* `UnwindCleanup(block)`
Also support unwind resume and unwind terminate terminators:
* `UnwindResume()`
* `UnwindTerminate(reason)`
Always point at index span on index obligation failure
Use more targetted span for index obligation failures by rewriting the obligation cause span.
CC #66023
Compute layout with spans for better cycle errors in coroutines
Split out from #117703, this PR at least gives us a nicer span to point at when we hit a cycle error in coroutine layout cycles.
`ReLateBound` -> `ReBound`
first step of https://github.com/rust-lang/types-team/issues/95
already fairly large xx
there's some future work here I intentionally did not contribute as part of this PR, from my notes:
- `DescriptionCtx` to `DescriptionCtxt`
- what is `CheckRegions::Bound`?
- `collect_late_bound_regions` et al
- `erase_late_bound_regions` -> `instantiate_bound_regions_with_erased`?
- `EraseEarlyRegions` should be removed, feels duplicate
r? `@BoxyUwU`
Deny more `~const` trait bounds
thereby fixing a family of ICEs (delayed bugs) for `feature(const_trait_impl, effects)` code.
As discussed
r? `@fee1-dead`
Add `std:#️⃣:{DefaultHasher, RandomState}` exports (needs FCP)
This implements rust-lang/libs-team#267 to move the libstd hasher types to `std::hash` where they belong, instead of `std::collections::hash_map`.
<details><summary>The below no longer applies, but is kept for clarity.</summary>
This is a small refactor for #27242, which moves the definitions of `RandomState` and `DefaultHasher` into `std::hash`, but in a way that won't be noticed in the public API.
I've opened rust-lang/libs-team#267 as a formal ACP to move these directly into the root of `std::hash`, but for now, they're at least separated out from the collections code in a way that will make moving that around easier.
I decided to simply copy the rustdoc for `std::hash` from `core::hash` since I think it would be ideal for the two to diverge longer-term, especially if the ACP is accepted. However, I would be willing to factor them out into a common markdown document if that's preferred.
</details>
Emit #[inline] on derive(Debug)
While working on https://github.com/rust-lang/rust/pull/116583 I noticed that the `cross_crate_inlinable` query identifies a lot of derived `Debug` impls as a MIR body that's little more than a call, which suggests they may be a good candidate for `#[inline]`. So here I've implemented that change specifically.
It seems to provide a nice improvement to build times.
generator layout: ignore fake borrows
fixes#117059
We emit fake shallow borrows in case the scrutinee place uses a `Deref` and there is a match guard. This is necessary to prevent the match guard from mutating the scrutinee: fab1054e17/compiler/rustc_mir_build/src/build/matches/mod.rs (L1250-L1265)
These fake borrows end up impacting the generator witness computation in `mir_generator_witnesses`, which causes the issue in #117059. This PR now completely ignores fake borrows during this computation. This is sound as thse are always removed after analysis and the actual computation of the generator layout happens afterwards.
Only the second commit impacts behavior, and could be backported by itself.
r? types
Extend builtin/auto trait args with error when they have >1 argument
Reuse `extend_with_error` to add error args to any auto trait (or built-in trait like `Copy` that is defined incorrectly) that has additional non-`Self` args.
Fixes#117628
patterns: reject raw pointers that are not just integers
Matching against `0 as *const i32` is fine, matching against `&42 as *const i32` is not.
This extends the existing check against function pointers and wide pointers: we now uniformly reject all these pointer types during valtree construction, and then later lint because of that. See [here](https://github.com/rust-lang/rust/pull/116930#issuecomment-1784654073) for some more explanation and context.
Also fixes https://github.com/rust-lang/rust/issues/116929.
Cc `@oli-obk` `@lcnr`
Rollup of 5 pull requests
Successful merges:
- #117263 (handle the case when the change-id isn't found)
- #117282 (Recover from incorrectly ordered/duplicated function keywords)
- #117679 (tests/rustdoc-json: Avoid needless use of `no_core` and `lang_items`)
- #117702 (target: move base and target specifications)
- #117713 (Add test for reexported hidden item with `--document-hidden-items`)
r? `@ghost`
`@rustbot` modify labels: rollup
Compute polonius loan scopes over the region graph
In issue #117146 a loan flows into an SCC containing a placeholder, and whose representative is an existential region. Since we currently compute loan scopes by looking at SCCs and their representatives only, polonius would compute kill points for this loan here whereas NLLs would not of course.
There are a few ways to fix this:
- don't try to be efficient by doing the computation over SCCs, and simply look for free regions and placeholders in the successors of the issuing region.
- change how the SCC representatives are picked, biasing towards placeholders over existential regions. They *shouldn't* matter much, but some downstream code may subtly depend on the current scheme (though no tests fail if we do such a change). This is for unrelated reasons also the way #116891 changes the representative computation. So that PR would also fix issue #117146.
- try to remove placeholders from the main path, and contain them to a pre-pass + a post-pass kind of polonius leak check. If possible, it would fix this issue by turning an outlives constraints to a placeholder into a constraint to 'static. This should also fix the issue, as the representative would be the free region in the SCC. We want to prototype this change to see if it's possible to try to simplify the borrowck main path from having to deal with placeholders and higher-ranked subtyping 🤞.
I'd like to take advantage of fuzzing and a crater run sooner rather than later, so that we grow more confidence that the 2 models are indeed equivalent empirically. Therefore this PR implements option 1 to fix the issue now.
We can take care of efficiency later after validation, and once we implement option 3 (which could also impact option 2 and that associated PR, maybe the lack of placeholders could remove the need to change the representative computation) to traverse SCCs and their representative again.
(Or we maybe will have some kind of naive position-dependent outlives propagation by then and this code would have been changed)
Fixes#117146.
r? `@matthewjasper`
Only use `normalize_param_env` when normalizing predicate in `check_item_bounds`
Only use the `normalize_param_env` when normalizing the item bound predicate in `check_item_bounds`, instead of using it when processing this obligation as well. This causes <BUG> to reoccur, but hopefully with better caching in the future, we can fix this would having such bad effects on perf.
This PR also fixes#117598. It turns out that the GAT predicate that we install is actually wrong -- given code like:
```
impl<'r> HasValueRef<'r> for Any {
type Database = Any;
}
```
We currently generate a predicate that looks like `<Any as HasValueRef<'r>>::Database = Any`, where `'r` is an early-bound variable. Really this GAT assumption should be universally quantified over the impl's args, i.e. `for<'r> <Any as HasValueRef<'r>>::Database = Any`, but then we'd need the binder to also include all the WC of the impl as well, which we don't support yet, lol.
