Commit graph

3455 commits

Author SHA1 Message Date
Ben Kimock
4e21e9e039 Remove some unnecessary normalization 2023-07-05 19:52:28 -04:00
bors
bf0e22b298 Auto merge of #108537 - GuillaumeGomez:rustdoc-search-whitespace-as-separator, r=notriddle
rustdoc: Allow whitespace as path separator like double colon

Fixes https://github.com/rust-lang/rust/issues/108447.

I think it makes sense since it allows more common cases, however it also makes the syntax heavier. Not sure what the rest of the team thinks about it. In any case we'll need to go through FCP.

Full explanation for the changes is available [here](https://github.com/rust-lang/rust/pull/108537#issuecomment-1589480564).

r? `@notriddle`
2023-07-02 18:49:29 +00:00
bors
131a03664e Auto merge of #113040 - Kobzol:llvm-remark-streamer, r=tmiasko
Add `-Zremark-dir` unstable flag to write LLVM optimization remarks to YAML

This PR adds an option for `rustc` to emit LLVM optimization remarks to a set of YAML files, which can then be digested by existing tools, like https://github.com/OfekShilon/optview2. When `-Cremark-dir` is passed, and remarks are enabled (`-Cremark=all`), the remarks will be now written to the specified directory, **instead** of being printed to standard error output.  The files are named based on the CGU from which they are being generated.

Currently, the remarks are written using the LLVM streaming machinery, directly in the diagnostics handler. It seemed easier than going back to Rust and then form there back to C++ to use the streamer from the diagnostics handler. But there are many ways to implement this, of course, so I'm open to suggestions :)

I included some comments with questions into the code. Also, I'm not sure how to test this.

r? `@tmiasko`
2023-07-02 12:48:44 +00:00
Jakub Beránek
62728c7aaf
Add rustc option to output LLVM optimization remarks to YAML files 2023-07-02 13:41:36 +02:00
Matthias Krüger
74a272d3d7
Rollup merge of #113231 - Urgau:fix_false_positive_drop_copy, r=Nilstrieb
Fix `dropping_copy_types` lint from linting in match-arm with side-effects

This PR fixes an issue with the `dropping_copy_types` and `dropping_references` lints when not all patterns that can have side-effects were detected and ignored.

Nearly _fixes_ https://github.com/rust-lang/rust/issues/112653 (will need beta-backport to completely fix the issue)
r? ``@Nilstrieb``
2023-07-02 10:27:21 +02:00
Matthias Krüger
37c50653fe
Rollup merge of #113228 - GuillaumeGomez:migrate-gui-test-color-18, r=notriddle
Migrate GUI colors test to original CSS color format

Follow-up of https://github.com/rust-lang/rust/pull/111459.

r? ``@notriddle``
2023-07-02 10:27:20 +02:00
bors
8e2d5e3a58 Auto merge of #112910 - lqd:mcp510, r=petrochenkov
Implement most of MCP510

This implements most of what remains to be done for MCP510:
- turns `-C link-self-contained` into a `+`/`-` list of components, like `-C link-self-contained=+linker,+crto,+libc,+unwind,+sanitizers,+mingw`. The scaffolding is present for all these expected components to be implemented and stabilized in the future on their own time. This PR only handles the `-Zgcc-ld=lld` subset of these link-self-contained components as  `-Clink-self-contained=+linker`
- handles  `-C link-self-contained=y|n`  as-is today, for compatibility with `rustc_codegen_ssa:🔙🔗:self_contained`'s [explicit opt-in and opt-out](9eee230cd0/compiler/rustc_codegen_ssa/src/back/link.rs (L1671-L1676)).
- therefore supports our plan to opt out of `rust-lld` (when it's enabled by default) even for current `-Clink-self-contained` users, with e.g. `-Clink-self-contained -Clink-self-contained=-linker`
- turns `add_gcc_ld_path` into its expected final form, by using the `-C link-self-contained=+linker`  CLI flag, and whether the `LinkerFlavor`  has the expected `Cc::Yes` and `Lld::Yes` shape (this is not yet the case in practice for any CLI linker flavor)
- makes the [new clean linker flavors](https://github.com/rust-lang/rust/pull/96827#issuecomment-1208441595) selectable in the CLI in addition to the legacy ones, in order to opt-in to using `cc` and `lld` to emulate `-Zgcc-ld=lld`
- ensure the new `-C link-self-contained` components, and `-C linker-flavor`s are unstable, and require `-Z unstable-options` to be used

The up-to-date set of flags for the future stable CLI version of `-Zgcc-ld=lld` is currently: `-Clink-self-contained=+linker -Clinker-flavor=gnu-lld-cc -Zunstable-options`.

It's possible we'll also need to do something for distros that don't ship `rust-lld`, but maybe there are already no tool search paths to be added to `cc` in this situation anyways.

r? `@petrochenkov`
2023-07-02 02:25:01 +00:00
Urgau
908574b5e7 Fix dropping_copy_types lint from linting in match-arm with side-effects 2023-07-01 16:05:55 +02:00
Matthias Krüger
ca7e27a71c
Rollup merge of #113182 - compiler-errors:rpit-stricter-captures, r=oli-obk
Error when RPITITs' hidden types capture more lifetimes than their trait definitions

This implements a stricter set of captures rules for RPITITs. They now may only capture:
1. Lifetimes from the impl header (both the self type and any trait substs -- we may want to restrict just to the self type's lifetimes, but the PR makes that easy to do, too)
2. Lifetimes mentioned by the `impl Trait` in the trait method's definition.

Namely, they may not mention lifetimes from the method (early or late) that are not mentioned in the `impl Trait`.

cc #105258 which I think was trying to do this too, though I'm not super familiar with what exactly differs from that or why that one was broken.
cc #112194 (doesn't fix this issue per se, because it's still an open question, but I think this is objectively better than the status quo, and gets us closer to resolving that issue.)

Technically is a fix for the ICE in #108580, but it turns that issue into an error now. We can decide separately whether or not nested RPITITs should capture lifetimes from their parents.

r? ``@oli-obk``
2023-07-01 13:46:01 +02:00
Matthias Krüger
9082287213
Rollup merge of #113174 - chenyukang:yukang-fix-102972-loop-next, r=compiler-errors
Better messages for next on a iterator inside for loops

Fixes #102972
2023-07-01 13:46:01 +02:00
Matthias Krüger
b63bc0645f
Rollup merge of #113168 - bvanjoi:fix-85992, r=petrochenkov
fix(resolve): skip assertion judgment when NonModule is dummy

Fixes #85992

## Why #85992 panic

During `resolve_imports`, the `path_res` of the import `issue_85992_extern_2::Outcome` is pointing to `external::issue_85992_extern_2` instead of `crate::issue_85992_extern_2`. As a result `import.imported_module.set` had been executed.

Attached 1: the state of `early_resolve_ident_in_lexical_scope` during the `resolve_imports` for `use issue_85992_extern_2::Outcome` is as follows:

|iter in `visit_scopes`  | `scope` | `result.binding` |
| -    | -               | -                                                            |
| init | -               | -                                                            |
| 0    | `CrateRoot`     | Err(Determined)     |
| 1    | `ExternPrelude` | pointing to the `issue_85992_extern_2`(external) |

However, during finalization for `issue_85992_extern_2::Outcome`, the `innermost_result` was pointed to `crate::issue_85992_extern_2` and no ambiguity was generated, leading to a panic.

Attached 2: the state of `early_resolve_ident_in_lexical_scope` during the `finalize_import` for `use issue_85992_extern_2::Outcome` is as follows:

|iter in `visit_scopes`  | `scope` | `result.binding` | `innermost_result` |
| -    | -               | -                                                            | -                     |
| init | -               | -                                                            | `None`                |
| 0    | `CrateRoot`     | pointing to `use crate::issue_85992_extern_2` **(introdcued by dummy)**    | same as `result` but with a `Some` wapper|
| 1    | `ExternPrelude` | pointing to the `issue_85992_extern_2`(external) | smae as above |

## Try to solve

Skip assertion judgment when `NonModule` is dummy

r? `@petrochenkov`
2023-07-01 13:46:00 +02:00
Guillaume Gomez
c607e206be Migrate GUI colors test to original CSS color format 2023-07-01 13:18:28 +02:00
bors
e5bb341f0e Auto merge of #111992 - ferrocene:pa-panic-abort-tests-bench, r=m-ou-se
Test benchmarks with `-Z panic-abort-tests`

During test execution, when a `#[bench]` benchmark is encountered it's executed once to check whether it works. Unfortunately that was not compatible with `-Z panic-abort-tests`: the feature works by spawning a subprocess for each test, which prevents the use of dynamic tests as we cannot pass closures to child processes, and before this PR the conversion from benchmark to test was done by turning benchmarks into dynamic tests whose closures execute the benchmark once.

The approach this PR took was to add two new kinds of `TestFn`s: `StaticBenchAsTestFn` and `DynBenchAsTestFn` (⚠️ **this is a breaking change** ⚠️). With that change, a `StaticBenchFn` can be converted into a `StaticBenchAsTestFn` without creating dynamic tests, and making it possible to test `#[bench]` functions with `-Z panic-abort-tests`. The subprocess test runner also had to be updated to perform the conversion from benchmark to test when appropriate.

Along with the bug fix, in the first commit I refactored how tests are executed: rather than executing the test function in multiple places across `libtest`, there is now a private `TestFn::into_runnable()` method, which returns either a `RunnableTest` or `RunnableBench`, on which you can call the `run()` method. This simplified the rest of the changes in the PR.

This PR is best reviewed commit-by-commit.
Fixes https://github.com/rust-lang/rust/issues/73509
2023-07-01 07:07:50 +00:00
bohan
549f48d0ed fix(resolve): skip assertion judgment when NonModule is dummy 2023-07-01 11:53:31 +08:00
Rémy Rakic
38f5a9964b comment, and bless, unstable linker flavor test 2023-06-30 21:13:24 +00:00
Rémy Rakic
6594f365fe add end-to-end test 2023-06-30 21:13:24 +00:00
Rémy Rakic
4ff780be2f bless test with new linker flavors 2023-06-30 21:13:24 +00:00
Guillaume Gomez
60c657f73a Improve search-result-display.goml test 2023-06-30 11:45:42 +02:00
yukang
44a8a8d0ca Better messages for next in a iterator inside for loops 2023-06-30 14:02:02 +08:00
Matthias Krüger
207b24413c
Rollup merge of #113177 - estebank:hrlt-sugg, r=compiler-errors
Use structured suggestion when telling user about `for<'a>`

```
error[E0637]: `&` without an explicit lifetime name cannot be used here
  --> $DIR/E0637.rs:13:13
   |
LL |     T: Into<&u32>,
   |             ^ explicit lifetime name needed here
   |
help: consider introducing a higher-ranked lifetime here
   |
LL |     T: for<'a> Into<&'a u32>,
   |        +++++++       ++
```
2023-06-30 08:01:14 +02:00
Matthias Krüger
38e6bba9c1
Rollup merge of #113171 - spastorino:new-rpitit-25, r=compiler-errors
Properly implement variances_of for RPITIT GAT

This fixes some of the issues found by crater run in https://github.com/rust-lang/rust/pull/112988#issuecomment-1610019572

r? ``@compiler-errors``
2023-06-30 08:01:14 +02:00
Matthias Krüger
c8f50ee111
Rollup merge of #113165 - compiler-errors:rpitits-foreign-bounds, r=spastorino
Encode item bounds for `DefKind::ImplTraitPlaceholder`

This was lost in a refactoring -- `hir::ItemKind::OpaqueTy` doesn't always map to `DefKind::Opaque`, specifically for RPITITs, so the check was migrated subtly wrong, and unfortunately I never had a test for this 🙃

Fixes #113155

r? ``@cjgillot``
2023-06-30 08:01:13 +02:00
Matthias Krüger
0b96b25bdf
Rollup merge of #113071 - compiler-errors:no-parent-non-lifetime-args-in-apit, r=eholk
Account for late-bound vars from parent arg-position impl trait

We should be reporting an error like we do for late-bound args coming from a parent APIT.

Fixes #113016
2023-06-30 08:01:13 +02:00
Matthias Krüger
6c22e0419f
Rollup merge of #111403 - y21:suggest-slice-swap, r=compiler-errors
suggest `slice::swap` for `mem::swap(&mut x[0], &mut x[1])` borrowck error

Recently saw someone ask why this code (example slightly modified):
```rs
fn main() {
  let mut foo = [1, 2];
  std::mem::swap(&mut foo[0], &mut foo[1]);
}
```
triggers this error and how to fix it:
```
error[E0499]: cannot borrow `foo[_]` as mutable more than once at a time
 --> src/main.rs:4:33
  |
4 |     std::mem::swap(&mut foo[0], &mut foo[1]);
  |     -------------- -----------  ^^^^^^^^^^^ second mutable borrow occurs here
  |     |              |
  |     |              first mutable borrow occurs here
  |     first borrow later used by call
  |
  = help: consider using `.split_at_mut(position)` or similar method to obtain two mutable non-overlapping sub-slices
```
The current help message is nice and goes in the right direction, but I think we can do better for this specific instance and suggest `slice::swap`, which makes this compile
2023-06-30 08:01:12 +02:00
bors
97279e91d8 Auto merge of #113162 - matthiaskrgr:rollup-fct3wj7, r=matthiaskrgr
Rollup of 7 pull requests

Successful merges:

 - #111322 (Support for native WASM exceptions)
 - #112086 (resolve: Remove artificial import ambiguity errors)
 - #112234 (refactor `tool_doc!`)
 - #112300 (Convert `run-make/coverage-reports` tests to use a custom compiletest mode)
 - #112795 (Migrate some rustc_builtin_macros to SessionDiagnostic)
 - #113144 (Make the `Elaboratable` trait take clauses)
 - #113161 (Fix type privacy lints error message)

r? `@ghost`
`@rustbot` modify labels: rollup
2023-06-30 03:27:42 +00:00
Michael Goulet
8ad5ea7b01 Adapt tests from #105258 2023-06-30 02:39:07 +00:00
Michael Goulet
473c88dfb6 Flip the order of binder instantiation for better diagnostics 2023-06-30 02:17:07 +00:00
Michael Goulet
d567e4f8b6 Error for RPITIT hidden tys that capture more than their trait defn 2023-06-30 02:17:07 +00:00
Santiago Pastorino
a10406318e
Properly implement variances_of for RPITIT GAT 2023-06-29 23:08:32 -03:00
Esteban Küber
7d33094d3a Use structured suggestion when telling user about for<'a>
```
error[E0637]: `&` without an explicit lifetime name cannot be used here
  --> $DIR/E0637.rs:13:13
   |
LL |     T: Into<&u32>,
   |             ^ explicit lifetime name needed here
   |
help: consider introducing a higher-ranked lifetime here
   |
LL |     T: for<'a> Into<&'a u32>,
   |        +++++++       ++
```
2023-06-30 00:34:14 +00:00
bors
330727467b Auto merge of #112682 - spastorino:new-rpitit-21, r=compiler-errors
Add bidirectional where clauses on RPITIT synthesized GATs

Given the following:

```rust
struct MyStruct<'a, T>(&'a T);

trait MyTrait<'a, T> {
    fn my_fn<'b, 'c, 'd, V>(item: &'c String) -> impl Sized + 'a + 'b + 'c where V: 'b, V: 'd;
}

impl<'a, T> MyTrait<'a, T> for MyStruct<'a, T> {
    fn my_fn<'b, 'c, 'd, V>(_: &'c String) -> impl Sized + 'a + 'b + 'c
    where
        V: 'b,
        V: 'd,
    {
        unimplemented!();
    }
}
```

We need the desugaring to be:

```rust
trait MyTrait<'a, T> {
    type MyFn<'bf, 'df, Vf, 'a2, 'b2, 'c2>: Sized + 'a2 + 'b2 + 'c2 where Vf: 'b2, 'a2: 'a, 'a: 'a2, 'b2: 'bf, 'bf: 'b2;

    fn my_fn<'b, 'c, 'd, V>(item: &'c String) -> MyStruct<'a>::MyFn<'b, 'd, V, 'a, 'b, 'c> where V: 'b, V: 'd {
        type opaque<'a3, 'b3, 'c3>;
    };
}

impl<'a, T> MyIter<'a, T> for MyStruct<'a, T> {
    type MyFn<'bf, 'df, Vf, 'a2, 'b2, 'c2> = impl Sized + 'a2 + 'b2 + 'c2 where Vf: b2, 'a2: 'a, 'a: 'a2, 'b2: 'bf, 'bf: 'b2;

    fn my_fn<'b, 'c, 'd, V>(_: &'c String) -> MyStruct<'a>::MyFn<'a, 'b, 'c, V> where V: 'b, V: 'd {
        type opaque<'a3, 'b3, 'c3>;
        unimplemented!();
    }
}
```

This PR adds the where clauses for the `MyFn` generated GATs.

This is a draft with a very ugly solution so we can make comments over concrete code.

r? `@compiler-errors`
2023-06-29 21:24:51 +00:00
Santiago Pastorino
4925b57782
Add bidirectional where clauses on RPITIT synthesized GATs 2023-06-29 14:26:26 -03:00
y21
679c5be405 add slice::swap suggestion 2023-06-29 19:19:59 +02:00
Michael Goulet
0506250f8c Encode item bounds for DefKind::ImplTraitPlaceholder 2023-06-29 16:37:13 +00:00
bors
a20a04e5d6 Auto merge of #113108 - compiler-errors:normalize-opaques-with-late-bound-vars-again, r=jackh726
Normalize opaques with late-bound vars again

We have a hack in the compiler where if an opaque has escaping late-bound vars, we skip revealing it even though we *could* reveal it from a technical perspective. First of all, this is weird, since we really should be revealing all opaques in `Reveal::All` mode. Second of all, it causes subtle bugs (linked below).

I attempted to fix this in #100980, which was unfortunately reverted due to perf regressions on codebases that used really deeply nested futures in some interesting ways. The worst of which was #103423, which caused the project to hang on build. Another one was #104842, which was just a slow-down, but not a hang. I took some time afterwards to investigate how to rework `normalize_erasing_regions` to take advantage of better caching, but that effort kinda fizzled out (#104133).

However, recently, I was made aware of more bugs whose root cause is not revealing opaques during codegen. That made me want to fix this again -- in the process, interestingly, I took the the minimized example from https://github.com/rust-lang/rust/issues/103423#issuecomment-1292947043, and it doesn't seem to hang any more...

Thinking about this harder, there have been some changes to the way we lower and typecheck async futures that may have reduced the pathologically large number of outlives obligations (see description of #103423) that we were encountering when normalizing opaques with bound vars the last time around:
* #104321 (lower `async { .. }` directly as a generator that implements `Future`, removing the `from_generator` shim)
* #104833 (removing an `identity_future` fn that was wrapping desugared future generators)

... so given that I can see:
* No significant regression on rust perf bot (https://github.com/rust-lang/rust/pull/107620#issuecomment-1600070317)
* No timeouts in crater run I did (https://github.com/rust-lang/rust/pull/107620#issuecomment-1605428952, rechecked failing crates in https://github.com/rust-lang/rust/pull/107620#issuecomment-1605973434)

... and given that this PR:
* Fixes #104601
* Fixes #107557
* Fixes #109464
* Allows us to remove a `DefiningAnchor::Bubble` from codegen (75a8f68183)

I'm inclined to give this another shot at landing this. Best case, it just works -- worst case, we get more examples to study how we need to improve the compiler to make this work.

r? types
2023-06-29 15:37:11 +00:00
Matthias Krüger
4338683b94
Rollup merge of #113161 - Bryanskiy:err_msg, r=petrochenkov
Fix type privacy lints error message

Type privacy lints diagnostic messages are not related to spans.

r? `@petrochenkov`
2023-06-29 16:36:33 +02:00
Matthias Krüger
f00db43e97
Rollup merge of #112300 - Zalathar:run-coverage, r=wesleywiser
Convert `run-make/coverage-reports` tests to use a custom compiletest mode

I was frustrated by the fact that most of the coverage tests are glued together with makefiles and shell scripts, so I tried my hand at converting most of them over to a newly-implemented `run-coverage` mode/suite in compiletest.

This ~~*mostly*~~ resolves #85009, ~~though I've left a small number of the existing tests as-is because they would require more work to fix/support~~.

---

I had time to go back and add support for the more troublesome tests that I had initially skipped over, so this PR now manages to completely get rid of `run-make/coverage-reports`.

---

The patches are arranged as follows:

- Declare the new mode/suite in bootstrap
- Small changes to compiletest that will be used by the new mode
- Implement the new mode in compiletest
- Migrate most of the tests over
- Add more code to bootstrap and compiletest to support the remaining tests
- Migrate the remaining tests (with some temporary hacks to avoid re-blessing them)
- Remove the temporary hacks and re-bless the migrated tests
- Remove the unused remnants of `run-make/coverage-reports`
2023-06-29 16:36:31 +02:00
Bryanskiy
35c6a1d0f3 Fix type privacy lints error message 2023-06-29 16:24:07 +03:00
Vadim Petrochenkov
4dcce38cda resolve: Remove artificial import ambiguity errors 2023-06-29 13:42:58 +03:00
bors
de22388873 Auto merge of #113134 - TaKO8Ki:rollup-4hvqzf6, r=TaKO8Ki
Rollup of 5 pull requests

Successful merges:

 - #112946 (Improve cgu naming and ordering)
 - #113048 (Fix build on Solaris where fd-lock cannot be used.)
 - #113100 (Fix display of long items in search results)
 - #113107 (add check for ConstKind::Value(_) to in_operand())
 - #113119 (rustdoc: Reduce internal function visibility.)

r? `@ghost`
`@rustbot` modify labels: rollup
2023-06-29 07:07:37 +00:00
Matthias Krüger
7e1869f9b4
Rollup merge of #113137 - lukas-code:no-moving-references, r=compiler-errors
don't suggest `move` for borrows that aren't closures

fixes https://github.com/rust-lang/rust/issues/113087
2023-06-29 05:48:40 +02:00
Matthias Krüger
1963688f93
Rollup merge of #112929 - oli-obk:what_if_an_impl_item_just_doesnt_wanna_be_impld, r=compiler-errors
Test that we require implementing trait items whose bounds don't hold in the current impl

I initially tried to make most of these pass, but that's a big can of worms, so I'm just adding them as tests, considering we have no tests for these things.
2023-06-29 05:48:39 +02:00
Matthias Krüger
42a495da7e
Rollup merge of #112670 - petrochenkov:typriv, r=eholk
privacy: Type privacy lints fixes and cleanups

See individual commits.
Follow up to https://github.com/rust-lang/rust/pull/111801.
2023-06-29 05:48:39 +02:00
bors
75726cae37 Auto merge of #112629 - compiler-errors:atb-imply, r=jackh726
Make associated type bounds in supertrait position implied

`trait A: B<Assoc: C> {}` should be able to imply both `Self: B` and `<Self as B>::Assoc: C`. Adjust the way that we collect implied predicates to do so.

Fixes #112573
Fixes #112568
2023-06-28 23:58:28 +00:00
Lukas Markeffsky
5e83ddd279 don't suggest move for borrows that aren't closures 2023-06-28 23:56:58 +02:00
Takayuki Maeda
74d6958297
Rollup merge of #113107 - mj10021:issue-113012-fix, r=oli-obk
add check for ConstKind::Value(_) to in_operand()

Added check for valtree value to close #113012 which fixes the issue, although I am not sure if adding the check there is sound or not cc `@oli-obk`
2023-06-29 03:29:33 +09:00
Takayuki Maeda
5871bc8486
Rollup merge of #113100 - GuillaumeGomez:search-result-long-name, r=notriddle
Fix display of long items in search results

Fixes https://github.com/rust-lang/rust/issues/113060.

You can test the result [here](https://rustdoc.crud.net/imperio/search-result-long-name/lib2/index.html).

To make it a bit better, I also reduced a bit the size of the short documentation from half to 2 fifth of the width.

r? `@notriddle`
2023-06-29 03:29:33 +09:00
Dylan DPC
a70842c7d1
Rollup merge of #113094 - GuillaumeGomez:fix-invalid-div-tag-in-head, r=notriddle,fmease
Fix invalid HTML DIV tag used in HEAD

Fixes https://github.com/rust-lang/rust/issues/113067.

The issue also nicely explains the whole problem.

r? ``@notriddle``
2023-06-28 18:28:48 +05:30
Dylan DPC
e4e1a995dc
Rollup merge of #113019 - ericmarkmartin:warning-for-guard-non-exhaustion, r=fee1-dead
add note for non-exhaustive matches with guards

Associated issue: #92197

When a match statement includes guards on every match arm (and is therefore necessarily non-exhaustive), add a note to the error E0004 diagnostic noting this.
2023-06-28 18:28:47 +05:30
Dylan DPC
fc2c587cd0
Rollup merge of #112867 - compiler-errors:more-impl-source-nits, r=lcnr
More `ImplSource` nits

Even more clean-ups, I'll put this up in parallel with the `select_in_new_trait_solver` PR.

r? ``@lcnr``
2023-06-28 18:28:47 +05:30