The implied deref to statics introduced by HIR->THIR lowering is only
used to create place expressions, it lacks unsafe semantics.
It is also confusing, as there is no visible `*ident` in the source.
For both classes of "unsafe static" (extern static and static mut)
allow this operation.
We lack a clear story around `thread_local! { static mut }`, which
is actually its own category of item that reuses the static syntax but
has its own rules. It's possible they should be similarly included, but
in the absence of a good reason one way or another, we do not bless it.
Rollup of 9 pull requests
Successful merges:
- #117932 (Correct rustdoc section where we talk about rustdoc emitting errors on invalid code)
- #125990 (Rename `deprecated_safe` lint to `deprecated_safe_2024`)
- #127506 (rustc_target: add known safe s390x target features)
- #127820 (Rewrite and rename `issue-14698`. `issue-33329` and `issue-107094` `run-make` tests to rmake or ui)
- #127923 (Use reuse tool 4.0)
- #128008 (Start using `#[diagnostic::do_not_recommend]` in the standard library)
- #128036 (add more tests)
- #128051 (rustdoc: revert spacing change in item-table)
- #128059 (Add regression test for items list size (#128023))
r? `@ghost`
`@rustbot` modify labels: rollup
Start using `#[diagnostic::do_not_recommend]` in the standard library
This commit starts using `#[diagnostic::do_not_recommend]` in the standard library to improve some error messages. In this case we just hide a certain nightly only impl as suggested in #121521
The result in not perfect yet, but at least the `Yeet` suggestion is not shown anymore. I would consider that as a minor improvement.
Rewrite and rename `issue-14698`. `issue-33329` and `issue-107094` `run-make` tests to rmake or ui
Part of #121876 and the associated [Google Summer of Code project](https://blog.rust-lang.org/2024/05/01/gsoc-2024-selected-projects.html).
try-job: armhf-gnu
try-job: test-various
try-job: aarch64-apple
try-job: x86_64-msvc
rustc_target: add known safe s390x target features
This pull request adds known safe target features for s390x (aka IBM Z systems).
Currently, these features are unstable since stabilizing the target features requires submitting proposals.
The `vector` feature was added in IBM Z13 (`arch11`), and this is a SIMD feature for the newer IBM Z systems.
The `backchain` attribute is the IBM Z way of adding frame pointers like unwinding capabilities (the "frame-pointer" switch on IBM Z and IBM POWER platforms will add _emulated_ frame pointers to the binary, which profilers can't use for unwinding the stack).
Both attributes can be applied at the LLVM module or function levels. However, the `backchain` attribute has to be enabled for all the functions in the call stack to get a successful unwind process.
Uplift most type-system related error reporting from `rustc_infer` to `rustc_trait_selection`
Completes the major part of #127492. The only cleanup that's needed afterwards is to actually use normalization in favor of the callback where needed, and deleting `can_eq_shallow`.
r? lcnr
Sorry for the large diff! Would prefer if comments can be handled in a follow-up (unless they're absolutely dealbreakers) because it seems bitrotty to let this sit.
Update wasi-sdk in CI to latest release
This commit updates the `wasi-sdk` download used by the `wasm32-wasi*` targets. The motivation for this commit is generally just "keep things up to date" and is not intended to cause any issues or differences from before, just a routine update.
This commit starts using `#[diagnostic::do_not_recommend]` in the
standard library to improve some error messages. In this case we just
hide a certain nightly only impl as suggested in #121521
Don't output incremental test artifacts into working directory
Currently tests can ICE when the test spits out `inc-fat` incremental artifacts directly into the top of the git checkout, and then the compiler version changes, and it reads nonsense incremental artifacts on a subsequent test run.
r? `@oli-obk`
cc `@Oneirical,` I think you added this -- I think the right flag to add when porting `-Cincremental` run-make tests is to use `//@ incremental` rather than manually specifying the `-Cincremental` rustflag.
Explain why we require `_` for empty patterns
This adds a note to the "non-exhaustive patterns" diagnostic to explain why we sometimes require extra `_` patterns on empty types. This is one of the two diagnostic improvements I wanted to do before [stabilizing `min_exhaustive_patterns`](https://github.com/rust-lang/rust/pull/122792).
r? ``@compiler-errors``
Just totally fully deny late-bound consts
Kinda don't care about supporting this until we have where clauses on binders. They're super busted and should be reworked in due time, and they are approximately 100% useless until then 😸Fixes#127970Fixes#127009
r? ``@BoxyUwU``
Remove unnecessary impl sorting in queries and metadata
Removes unnecessary impl sorting because queries already return their keys in HIR definition order: https://github.com/rust-lang/rust/issues/120371#issuecomment-1926422838
r? `@cjgillot` or `@lcnr` -- unless I totally misunderstood what was being asked for here? 😆fixes#120371
Forbid borrows and unsized types from being used as the type of a const generic under `adt_const_params`
Fixes#112219Fixes#112124Fixes#112125
### Motivation
Currently the `adt_const_params` feature allows writing `Foo<const N: [u8]>` this is entirely useless as it is not possible to write an expression which evaluates to a type that is not `Sized`. In order to actually use unsized types in const generics they are typically written as `const N: &[u8]` which *is* possible to provide a value of.
Unfortunately allowing the types of const parameters to contain references is non trivial (#120961) as it introduces a number of difficult questions about how equality of references in the type system should behave. References in the types of const generics is largely only useful for using unsized types in const generics.
This PR introduces a new feature gate `unsized_const_parameters` and moves support for `const N: [u8]` and `const N: &...` from `adt_const_params` into it. The goal here hopefully is to experiment with allowing `const N: [u8]` to work without references and then eventually completely forbid references in const generics.
Splitting this out into a new feature gate means that stabilization of `adt_const_params` does not have to resolve#120961 which is the only remaining "big" blocker for the feature. Remaining issues after this are a few ICEs and naming bikeshed for `ConstParamTy`.
### Implementation
The implementation is slightly subtle here as we would like to ensure that a stabilization of `adt_const_params` is forwards compatible with any outcome of `unsized_const_parameters`. This is inherently tricky as we do not support unstable trait implementations and we determine whether a type is valid as the type of a const parameter via a trait bound.
There are a few constraints here:
- We would like to *allow for the possibility* of adding a `Sized` supertrait to `ConstParamTy` in the event that we wind up opting to not support unsized types and instead requiring people to write the 'sized version', e.g. `const N: [u8; M]` instead of `const N: [u8]`.
- Crates should be able to enable `unsized_const_parameters` and write trait implementations of `ConstParamTy` for `!Sized` types without downstream crates that only enable `adt_const_params` being able to observe this (required for std to be able to `impl<T> ConstParamTy for [T]`
Ultimately the way this is accomplished is via having two traits (sad), `ConstParamTy` and `UnsizedConstParamTy`. Depending on whether `unsized_const_parameters` is enabled or not we change which trait is used to check whether a type is allowed to be a const parameter.
Long term (when stabilizing `UnsizedConstParamTy`) it should be possible to completely merge these traits (and derive macros), only having a single `trait ConstParamTy` and `macro ConstParamTy`.
Under `adt_const_params` it is now illegal to directly refer to `ConstParamTy` it is only used as an internal impl detail by `derive(ConstParamTy)` and checking const parameters are well formed. This is necessary in order to ensure forwards compatibility with all possible future directions for `feature(unsized_const_parameters)`.
Generally the intuition here should be that `ConstParamTy` is the stable trait that everything uses, and `UnsizedConstParamTy` is that plus unstable implementations (well, I suppose `ConstParamTy` isn't stable yet :P).
reenable some windows tests
Locally passing on `x86_64-pc-windows-msvc`, fingers crossed for `*-pc-windows-gnu`.
try-job: x86_64-msvc
try-job: x86_64-mingw
