- only borrow the refcell once per loop
- avoid complex matches to reduce branch paths in the hot loop
- use a by-ref fast path that avoids mutations at the expense of having false negatives
Install projection from RPITIT to default trait method opaque correctly
1. For new lowering strategy `-Zlower-impl-trait-in-trait-to-assoc-ty`, install the correct default trait method projection predicates (RPITIT -> opaque). This makes default trait body tests pass!
2. Fix two WF-checking bugs -- first, we want to make sure that we're always looking for an opaque type in `check_return_position_impl_trait_in_trait_bounds`. That's because the RPITIT projections are normalized to opaques during wfcheck. Second, fix RPITIT's param-envs by not adding the projection predicates that we install on trait methods to make default RPITITs work -- I left a comment why.
3. Also, just a small drive-by for `rustc_on_unimplemented`. Not sure if it affects any tests, but can't hurt.
r? ````@spastorino,```` based off of #109140
Remove box expressions from HIR
After #108516, `#[rustc_box]` is used at HIR->THIR lowering and this is no longer emitted, so it can be removed.
This is based on top of #108471 to help with conflicts, so 43490488ccacd1a822e9c621f5ed6fca99959a0b is the only relevant commit (sorry for all the duplicated pings!)
````@rustbot```` label +S-blocked
Some cleanups in our normalization logic
Changed a match to be exhaustive and deduplicated some code.
r? ```@compiler-errors```
this pulls out the uncontroversial part of https://github.com/rust-lang/rust/pull/108860
make `define_opaque_types` fully explicit
based on the idea of #108389. Moved `define_opaque_types` into the actual operations, e.g. `eq`, instead of `infcx.at` because normalization doesn't use `define_opaque_types` and even creates it's own `At` with a different `define_opaque_types` internally.
Somewhat surprisingly, coherence actually relies on `DefineOpaqueTypes::Yes` for soundness which was revealed because I've incorrectly used `DefineOpaqueTypes::No` in `equate_impl_headers`. It feels concerning that even though this is the case, we still sometimes use `DefineOpaqueTypes::No` in coherence. I did not look into this as part of this PR as it is purely changing the structure of the code without changing behavior in any way.
r? ```@oli-obk```
Remove some direct calls to local_def_id_to_hir_id on diagnostics
Was playing with `tests/ui/impl-trait/in-trait/default-body-with-rpit.rs` and was able to remove some ICEs. Still getting ...
```
error[E0277]: `impl Future<Output = Foo::{opaque#0}>` is not a future
--> tests/ui/impl-trait/in-trait/default-body-with-rpit.rs:10:28
|
10 | async fn baz(&self) -> impl Debug {
| ^^^^^^^^^^ `impl Future<Output = Foo::{opaque#0}>` is not a future
|
= help: the trait `Future` is not implemented for `impl Future<Output = Foo::{opaque#0}>`
= note: impl Future<Output = Foo::{opaque#0}> must be a future or must implement `IntoFuture` to be awaited
note: required by a bound in `Foo::{opaque#1}`
--> tests/ui/impl-trait/in-trait/default-body-with-rpit.rs:10:28
|
10 | async fn baz(&self) -> impl Debug {
| ^^^^^^^^^^ required by this bound in `Foo::{opaque#1}`
error[E0277]: the size for values of type `impl Future<Output = Foo::{opaque#0}>` cannot be known at compilation time
--> tests/ui/impl-trait/in-trait/default-body-with-rpit.rs:10:28
|
10 | async fn baz(&self) -> impl Debug {
| ^^^^^^^^^^ doesn't have a size known at compile-time
|
= help: the trait `Sized` is not implemented for `impl Future<Output = Foo::{opaque#0}>`
note: required by a bound in `Foo::{opaque#1}`
--> tests/ui/impl-trait/in-trait/default-body-with-rpit.rs:10:28
|
10 | async fn baz(&self) -> impl Debug {
| ^^^^^^^^^^ required by this bound in `Foo::{opaque#1}`
error: internal compiler error: compiler/rustc_hir_typeck/src/closure.rs:724:18: async fn generator return type not an inference variable: Foo::{opaque#1}<'_>
--> tests/ui/impl-trait/in-trait/default-body-with-rpit.rs:10:39
|
10 | async fn baz(&self) -> impl Debug {
| _______________________________________^
11 | | ""
12 | | }
| |_____^
```
But I guess this is a little bit of progress anyway.
This one goes on top of #108700 and #108945
r? `@compiler-errors`
Remove `identity_future` indirection
This was previously needed because the indirection used to hide some unexplained lifetime errors, which it turned out were related to the `min_choice` algorithm.
Removing the indirection also solves a couple of cycle errors, large moves and makes async blocks support the `#[track_caller]`annotation.
Fixes https://github.com/rust-lang/rust/issues/104826.
Add suggestion to diagnostic when user has array but trait wants slice. (rebased)
Rebase of #91314, except for change to multipart suggestion
Resolves#90528
r? ``@compiler-errors`` since you requested the multipart suggestion
tidy: enforce comment blocks to have an even number of backticks
After PR #108694, most unmatched backticks in `compiler/` comments have been eliminated. This PR adds a tidy lint to ensure no new unmatched backticks are added, and either addresses the lint in the remaining instances it found, or allows it.
Very often, backtick containing sections wrap around lines, for example:
```Rust
// This function takes a tuple `(Vec<String>,
// Box<[u8]>)` and transforms it into `Vec<u8>`.
```
The lint is implemented to work on top of blocks, counting each line with a `//` into a block, and counting if there are an odd or even number of backticks in the entire block, instead of looking at just a single line.
This makes it easier to open the messages file while developing on features.
The commit was the result of automatted changes:
for p in compiler/rustc_*; do mv $p/locales/en-US.ftl $p/messages.ftl; rmdir $p/locales; done
for p in compiler/rustc_*; do sed -i "s#\.\./locales/en-US.ftl#../messages.ftl#" $p/src/lib.rs; done
Implement goal caching with the new solver
Maybe it's wrong, idk. Opening mostly for first impressions before I go to sleep.
r? ``@lcnr,`` cc ``@cjgillot``
Don't even try to combine consts with incompatible types
~I left a more detailed explanation for why this fixes this issue in the UI test, but in general, we should not try to unify const infer vars and rigid consts if they have incompatible types. That's because we don't want something like a `ConstArgHasType` predicate to suddenly go from passing to failing, or vice versa, due to a shallow resolve.~
1. Use the `type_of` for a parameter in `try_eval_lit_or_param`, instead of the "expected" type from a `WithOptConstParam` def id.
2. Don't combine consts that have incompatible types.
Fixes#108781
Do not ICE when we have fn pointer `Fn` obligations with bound vars in the self type
We never supported solving `for<'a> fn(&'a ()): Fn(&'a ())` -- I tried to add that support in #104929, but iirc `@lcnr` wanted to support this more generally by eagerly instantiating trait predicate binders with placeholders. That never happened due to blockers in the old solver, but we probably shouldn't ICE in any case.
On the bright side, this passes on the new solver :^)
Emit alias-eq when equating numeric var and projection
This doesn't fix everything having to do with projections and infer vars, but it does fix a common case I saw in HIR typeck.
r? `@lcnr`
Remove `body_def_id` from `Inherited`
We can just use the body id from the obligation cause.
Follow-up to #108945, only my commit is relevant.
r? `@cjgillot` cc `@spastorino`
Rollup of 8 pull requests
Successful merges:
- #108754 (Retry `pred_known_to_hold_modulo_regions` with fulfillment if ambiguous)
- #108759 (1.41.1 supported 32-bit Apple targets)
- #108839 (Canonicalize root var when making response from new solver)
- #108856 (Remove DropAndReplace terminator)
- #108882 (Tweak E0740)
- #108898 (Set `LIBC_CHECK_CFG=1` when building Rust code in bootstrap)
- #108911 (Improve rustdoc-gui/tester.js code a bit)
- #108916 (Remove an unused return value in `rustc_hir_typeck`)
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
Canonicalize root var when making response from new solver
During trait solving, if we equate two inference variables `?0` and `?1` but don't equate them with any rigid types, then `InferCtxt::probe_ty_var` will return `Err` for both of these. The canonicalizer code will then canonicalize the variables independently(!), and the response will not reflect the fact that these two variables have been made equal.
This hinders inference and I also don't think it's sound? I haven't thought too much about it past that, so let's talk about it.
r? ``@lcnr``
Retry `pred_known_to_hold_modulo_regions` with fulfillment if ambiguous
Fixes#108721
The problem here is that when we're checking `is_sized_raw` during codegen on some type that has a lot of opaques in it, something emits several nested obligations that are individually ambiguous, but when processed together in a loop then apply modulo regions. Since the `evaluate_predicates_recursively` inner loop doesn't process predicates until they stop changing, we return `EvaluatedToAmbig`, which makes the sized check return false incorrectly. See:
f15f0ea739/compiler/rustc_trait_selection/src/traits/select/mod.rs (L596-L606)
... Compared to the analogous loop in the new solver:
f15f0ea739/compiler/rustc_trait_selection/src/solve/mod.rs (L481-L512)
To fix this, if we get ambiguous during `pred_known_to_hold_modulo_regions`, just retry the obligation in a fulfillment context.
--
Unfortunately... I don't have a test for this. I've only tested this locally. Pending minimization :/
r? types
