Don't pick `T: FnPtr` nested goals as the leaf goal in diagnostics for new solver
r? `@lcnr`
See `tests/ui/traits/next-solver/diagnostics/dont-pick-fnptr-bound-as-leaf.rs` for a minimized example of what code this affects the diagnostics off. The output of running nightly `-Znext-solver` on that test is the following:
```
error[E0277]: the trait bound `Foo: Trait` is not satisfied
--> src/lib.rs:14:20
|
14 | requires_trait(Foo);
| -------------- ^^^ the trait `FnPtr` is not implemented for `Foo`
| |
| required by a bound introduced by this call
|
note: required for `Foo` to implement `Trait`
--> src/lib.rs:7:16
|
7 | impl<T: FnPtr> Trait for T {}
| ----- ^^^^^ ^
| |
| unsatisfied trait bound introduced here
note: required by a bound in `requires_trait`
--> src/lib.rs:11:22
|
11 | fn requires_trait<T: Trait>(_: T) {}
| ^^^^^ required by this bound in `requires_trait`
```
Part of rust-lang/trait-system-refactor-initiative#148
Use `structurally_normalize` instead of manual `normalizes-to` goals in alias relate errors
r? `@lcnr`
I added `structurally_normalize_term` so that code that is generic over ty or const can use the structurally normalize helpers. See `tests/ui/traits/next-solver/diagnostics/alias_relate_error_uses_structurally_normalize.rs` for a description of the reason for the (now fixed) ICEs
Refactor dyn-compatibility error and suggestions
This CL makes a number of small changes to dyn compatibility errors:
- "object safety" has been renamed to "dyn-compatibility" throughout
- "Convert to enum" suggestions are no longer generated when there exists a type-generic impl of the trait or an impl for `dyn OtherTrait`
- Several error messages are reorganized for user readability
Additionally, the dyn compatibility error creation code has been split out into functions.
cc #132713
cc #133267
r? `@compiler-errors`
This CL makes a number of small changes to dyn compatibility errors:
- "object safety" has been renamed to "dyn-compatibility" throughout
- "Convert to enum" suggestions are no longer generated when there
exists a type-generic impl of the trait or an impl for `dyn OtherTrait`
- Several error messages are reorganized for user readability
Additionally, the dyn compatibility error creation code has been
split out into functions.
cc #132713
cc #133267
Properly record metavar spans for other expansions other than TT
This properly records metavar spans for nonterminals other than tokentree. This means that we operations like `span.to(other_span)` work correctly for macros. As you can see, other diagnostics involving metavars have improved as a result.
Fixes#132908
Alternative to #133270
cc `@ehuss`
cc `@petrochenkov`
Add fixme and test for issue #135289
This PR:
- adds a test minimizing issue #135289 for PR #135310
- adds a fixme about the suboptimal fix for the ICE
I've verified the test indeed ICEs with 3f2f695d68 reverted.
r? `@estebank`
remove support for the (unstable) #[start] attribute
As explained by `@Noratrieb:`
`#[start]` should be deleted. It's nothing but an accidentally leaked implementation detail that's a not very useful mix between "portable" entrypoint logic and bad abstraction.
I think the way the stable user-facing entrypoint should work (and works today on stable) is pretty simple:
- `std`-using cross-platform programs should use `fn main()`. the compiler, together with `std`, will then ensure that code ends up at `main` (by having a platform-specific entrypoint that gets directed through `lang_start` in `std` to `main` - but that's just an implementation detail)
- `no_std` platform-specific programs should use `#![no_main]` and define their own platform-specific entrypoint symbol with `#[no_mangle]`, like `main`, `_start`, `WinMain` or `my_embedded_platform_wants_to_start_here`. most of them only support a single platform anyways, and need cfg for the different platform's ways of passing arguments or other things *anyways*
`#[start]` is in a super weird position of being neither of those two. It tries to pretend that it's cross-platform, but its signature is a total lie. Those arguments are just stubbed out to zero on ~~Windows~~ wasm, for example. It also only handles the platform-specific entrypoints for a few platforms that are supported by `std`, like Windows or Unix-likes. `my_embedded_platform_wants_to_start_here` can't use it, and neither could a libc-less Linux program.
So we have an attribute that only works in some cases anyways, that has a signature that's a total lie (and a signature that, as I might want to add, has changed recently, and that I definitely would not be comfortable giving *any* stability guarantees on), and where there's a pretty easy way to get things working without it in the first place.
Note that this feature has **not** been RFCed in the first place.
*This comment was posted [in May](https://github.com/rust-lang/rust/issues/29633#issuecomment-2088596042) and so far nobody spoke up in that issue with a usecase that would require keeping the attribute.*
Closes https://github.com/rust-lang/rust/issues/29633
try-job: x86_64-gnu-nopt
try-job: x86_64-msvc-1
try-job: x86_64-msvc-2
try-job: test-various
Rework dyn trait lowering to stop being so intertwined with trait alias expansion
This PR reworks the trait object lowering code to stop handling trait aliases so funky, and removes the `TraitAliasExpander` in favor of a much simpler design. This refactoring is important for making the code that I'm writing in https://github.com/rust-lang/rust/pull/133397 understandable and easy to maintain, so the diagnostics regressions are IMO inevitable.
In the old trait object lowering code, we used to be a bit sloppy with the lists of traits in their unexpanded and expanded forms. This PR largely rewrites this logic to expand the trait aliases *once* and handle them more responsibly throughout afterwards.
Please review this with whitespace disabled.
r? lcnr
Rollup of 7 pull requests
Successful merges:
- #135542 (Add the concrete syntax for precise capturing to 1.82 release notes.)
- #135700 (Emit single privacy error for struct literal with multiple private fields and add test for `default_field_values` privacy)
- #135722 (make it possible to use ci-rustc on tarball sources)
- #135729 (Add debug assertions to compiler profile)
- #135736 (rustdoc: Fix flaky doctest test)
- #135738 (Replace usages of `map_or(bool, ...)` with `is_{some_and|none_or|ok_and}`)
- #135747 (Rename FileName::QuoteExpansion to CfgSpec)
r? `@ghost`
`@rustbot` modify labels: rollup
Match Ergonomics 2024: document and reorganize the currently-implemented feature gates
The hope here is to make it easier to adjust, understand, and test the experimental pattern typing rules implemented in the compiler. This PR doesn't (or at isn't intended to) change any behavior or add any new tests; I'll be handling that later. I've also included some reasoning/commentary on the more involved changes in the commit messages.
Relevant tracking issue: #123076
r? `@Nadrieril`
fully de-stabilize all custom inner attributes
`#![test]` and `#![rustfmt::skip]` were accidentally accepted in more places than they should. These have been marked as soft-unstable since forever (https://github.com/rust-lang/rust/pull/82399) and shown in future-compat reports since Rust 1.77 (https://github.com/rust-lang/rust/pull/116274).
Cc `@rust-lang/lang` `@petrochenkov`
Emit single privacy error for struct literal with multiple private fields and add test for `default_field_values` privacy
Add test ensuring that struct with default field values is not constructable if the fields are not accessible.
Collect all unreachable fields in a single struct literal struct and emit a single error, instead of one error per private field.
```
error[E0451]: fields `beta` and `gamma` of struct `Alpha` are private
--> $DIR/visibility.rs:18:13
|
LL | let _x = Alpha {
| ----- in this type
LL | beta: 0,
| ^^^^^^^ private field
LL | ..
| ^^ field `gamma` is private
```
Disallow `A { .. }` if `A` has no fields
```
error: `A` has no fields, `..` needs at least one default field in the struct definition
--> $DIR/empty-struct.rs:16:17
|
LL | let _ = A { .. };
| - ^^
| |
| this type has no fields
```
Fix ICE in resolving associated items as non-bindings
Fixes#135614 so that imported associated functions of traits can be shadowed by local bindings and associated constants of traits can be used in patterns.
```
error[E0797]: base expression required after `..`
--> $DIR/feature-gate-default-field-values.rs:62:21
|
LL | let x = Foo { .. };
| ^
|
help: add `#![feature(default_field_values)]` to the crate attributes to enable default values on `struct` fields
|
LL + #![feature(default_field_values)]
|
help: add a base expression here
|
LL | let x = Foo { ../* expr */ };
| ++++++++++
```
```
error: `size_of_val` is not yet stable as a const intrinsic
--> $DIR/const-unstable-intrinsic.rs:17:9
|
LL | unstable_intrinsic::size_of_val(&x);
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
= help: add `#![feature(unstable)]` to the crate attributes to enable
help: add `#![feature(unstable)]` to the crate attributes to enable
|
LL + #![feature("unstable")]
|
```
When encountering a call corresponding to an item marked as unstable behind a feature flag, provide a structured suggestion pointing at where in the crate the `#![feature(..)]` needs to be written.
```
error: `foobar` is not yet stable as a const fn
--> $DIR/const-stability-attribute-implies-no-feature.rs:12:5
|
LL | foobar();
| ^^^^^^^^
|
help: add `#![feature(const_foobar)]` to the crate attributes to enable
|
LL + #![feature(const_foobar)]
|
```
Fix#81370.
```
error: `A` has no fields, `..` needs at least one default field in the struct definition
--> $DIR/empty-struct.rs:16:17
|
LL | let _ = A { .. };
| - ^^
| |
| this type has no fields
```
Collect all unreachable fields in a single struct literal struct and emit a single error, instead of one error per private field.
```
error[E0451]: fields `beta` and `gamma` of struct `Alpha` are private
--> $DIR/visibility.rs:18:13
|
LL | let _x = Alpha {
| ----- in this type
LL | beta: 0,
| ^^^^^^^ private field
LL | ..
| ^^ field `gamma` is private
```
Rollup of 7 pull requests
Successful merges:
- #133700 (const-eval: detect more pointers as definitely not-null)
- #135290 (Encode constraints that hold at all points as logical edges in location-sensitive polonius)
- #135478 (Run clippy for rustc_codegen_gcc on CI)
- #135583 (Move `std::pipe::*` into `std::io`)
- #135612 (Include x scripts in tarballs)
- #135624 (ci: mirror buildkit image to ghcr)
- #135661 (Stabilize `float_next_up_down`)
r? `@ghost`
`@rustbot` modify labels: rollup
const-eval: detect more pointers as definitely not-null
This fixes https://github.com/rust-lang/rust/issues/133523 by making the `scalar_may_be_null` check smarter: for instance, an odd offset in any 2-aligned allocation can never be null, even if it is out-of-bounds.
More generally, if an allocation with unknown base address B is aligned to alignment N, and a pointer is at offset X inside that allocation, then we know that `(B + X) mod N = B mod N + X mod N = X mod N`. Since `0 mod N` is definitely 0, if we learn that `X mod N` is *not* 0 we can deduce that `B + X` is not 0.
This is immediately visible on stable, via `ptr.is_null()` (and, more subtly, by not raising a UB error when such a pointer is used somewhere that a non-null pointer is required). Therefore nominating for `@rust-lang/lang.`
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
```
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
```
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.
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
