new solver: prefer trivial builtin impls
As discussed [on zulip](https://rust-lang.zulipchat.com/#narrow/channel/364551-t-types.2Ftrait-system-refactor/topic/needs_help.3A.20trivial.20builtin.20impls), this PR:
- adds a new `BuiltinImplSource::Trivial` source, and marks the `Sized` builtin impls as trivial
- prefers these trivial builtin impls in `merge_trait_candidates`
The comments can likely be wordsmithed a bit better, and I ~stole~ was inspired by the old solver ones. Let me know how you want them improved.
When enabling the new solver for tests, 3 UI tests now pass:
- `regions/issue-26448-1.rs` and its sibling `regions/issue-26448-2.rs` were rejected by the new solver but accepted by the old one
- and `issues/issue-42796.rs` where the old solver emitted some overflow errors in addition to the expected error
(For some reason one of these tests is run-pass, but I can take care of that another day)
r? lcnr
Make tidy warn on unrecognized directives
This PR makes it so tidy warns on unrecognized directives, as recommended on [the discussion of #130984](https://github.com/rust-lang/rust/issues/130984#issuecomment-2589284620). This is edited from the previous version of this PR, which only warned on "tidy-ignore" and no other tidy directive typos.
Fixes#130984.
``@rustbot`` label A-tidy C-enhancement
This advances Fuchsia to a checkout from 2025-01-13, which corresponds
to a recent Rust roll, and hopefully avoids #135667, where a repository
used by the older version of Rust was accidentally archived and broke
checking out the prior version.
try-job: x86_64-fuchsia
```
error[E0451]: field `x` of struct `S` is private
--> $DIR/visibility.rs:24:9
|
LL | let a = baz::S {
| ------ in this type
LL | ..
| ^^ field `x` is private
```
```
error[E0451]: field `beta` of struct `Alpha` is private
--> $DIR/visibility.rs:11:37
|
LL | let x = crate::foo::Alpha { .. };
| ^^ field `beta` is private
```
Stable Hash: Ignore all HirIds that just identify the node itself
This should provide better incremental caching, but it seems there is more to it.
These IDs also serve no purpose being in the stable hash of the item they refer to, only when referring to *another* item is it important that we hash the `HirId`. So we can at least avoid the cost during stable hashing, even if we don't benefit from it by avoiding some queries' caches from being invalidated
Unsure how to make sure we do this right by construction. Would be nice to do something type based
Instead of materializing `Locations::All` constraints as physical edges
at all the points in the CFG, we record them as logical edges and only
materialize them during traversal as successors for a given node.
This fixes the slowness/hang in the `saturating-float-casts.rs` test.
Rollup of 6 pull requests
Successful merges:
- #131806 (Treat other items as functions for the purpose of type-based search)
- #134980 (Location-sensitive polonius prototype: endgame)
- #135558 (Detect if-else chains with a missing final else in type errors)
- #135594 (fix error for when results in a rustdoc-js test are in the wrong order)
- #135601 (Fix suggestion to convert dereference of raw pointer to ref)
- #135604 (Expand docs for `E0207` with additional example)
r? `@ghost`
`@rustbot` modify labels: rollup
Expand docs for `E0207` with additional example
Add an example to E0207 docs showing how to tie the lifetime of the self type to an associated type in an impl when the trait *doesn't* have a lifetime to begin with.
CC #135589.
Detect if-else chains with a missing final else in type errors
```
error[E0308]: `if` and `else` have incompatible types
--> $DIR/if-else-chain-missing-else.rs:12:12
|
LL | let x = if let Ok(x) = res {
| ______________-
LL | | x
| | - expected because of this
LL | | } else if let Err(e) = res {
| | ____________^
LL | || return Err(e);
LL | || };
| || ^
| ||_____|
| |_____`if` and `else` have incompatible types
| expected `i32`, found `()`
|
= note: `if` expressions without `else` evaluate to `()`
= note: consider adding an `else` block that evaluates to the expected type
```
We probably want a longer explanation and fewer spans on this case.
Partially address #133316.
Location-sensitive polonius prototype: endgame
This PR sets up the naive location-sensitive analysis end-to-end, and replaces the location-insensitive analysis. It's roughly all the in-progress work I wanted to land for the prototype, modulo cleanups I still want to do after the holidays, or the polonius debugger, and so on.
Here, we traverse the localized constraint graph, have to deal with kills and time-traveling (👌), and record that as loan liveness for the existing scope and active loans computations.
Then the near future looks like this, especially if the 2025h1 project goal is accepted:
- gradually bringing it up to completion
- analyzing and fixing the few remaining test failures
- going over the *numerous* fixmes in this prototype (one of which is similar to a hang on one test's millions and millions of constraints)
- trying to see how to lower the impact of the lack of NLL liveness optimization on diagnostics, and their categorization of local variables and temporaries (the vast majority of blessed expectations differences), as well as the couple ICEs trying to find an NLL constraint to blame for errors.
- dealing with the theoretical weakness around kills, conflating reachability for the two TCS, etc that is described ad nauseam in the code.
- switching the compare mode to the in-tree implementation, and blessing the diagnostics
- apart from the hang, it's not catastrophically slower on our test suite, so then we can try to enable it on CI
- checking crater, maybe trying to make it faster :3, etc.
I've tried to gradually introduce this PR's work over 4 commits, because it's kind of subtle/annoying, and Niko/I are not completely convinced yet. That one comment explaining the situation is maybe 30% of the PR 😓. Who knew that spacetime reachability and time-traveling could be mind bending.
I kinda found this late and the impact on this part of the computation was a bit unexpected to us. A bit more care/thought will be needed here. I've described my plan in the comments though. In any case, I believe we have the current implementation is a conservative approximation that shouldn't result in unsoundness but false positives at worst. So it feels fine for now.
r? ``@jackh726``
---
Fixes#127628 -- which was a assertion triggered for a difference in loan computation between NLLs and the location-insensitive analysis. That doesn't exist anymore so I've removed this crash test.
Treat other items as functions for the purpose of type-based search
specifically, constants and statics are nullary functions, and struct fields are unary functions.
fixes#130204
r? ``@notriddle``
Add gpu-kernel calling convention
The amdgpu-kernel calling convention was reverted in commit f6b21e90d1 (#120495 and https://github.com/rust-lang/rust-analyzer/pull/16463) due to inactivity in the amdgpu target.
Introduce a `gpu-kernel` calling convention that translates to `ptx_kernel` or `amdgpu_kernel`, depending on the target that rust compiles for.
Tracking issue: #135467
amdgpu target tracking issue: #135024
bootstrap: still require `COMPILETEST_FORCE_STAGE0` for `./x test rustdoc-js --stage 0`
This PR reverts #135375, because through some more testing I found out `./x test rustdoc-js --stage 0` does not in fact build rustdoc, and all the tests fail. This can't be intended behavior, so at least require `COMPILETEST_FORCE_STAGE0` to make it less likely to run `rustdoc-js --stage 0` by accident.
The problem that `--stage 0` is not working at all for this rustdoc-js test suite is tracked over at #135603.
cc `@lolbinarycat`
r? bootstrap
