Add the `#[derive_const]` attribute
Closes#102371. This is a minimal patchset for the attribute to work. There are no restrictions on what traits this attribute applies to.
r? `````@oli-obk`````
Enable varargs support for calling conventions other than C or cdecl
This patch makes it possible to use varargs for calling conventions,
which are either based on C (efiapi) or C is based on them (sysv64 and win64).
Also pinging ``@phlopsi,`` because he noticed first this oversight when writing a library for UEFI.
Allow `impl Fn() -> impl Trait` in return position
_This was originally proposed as part of #93082 which was [closed](https://github.com/rust-lang/rust/pull/93082#issuecomment-1027225715) due to allowing `impl Fn() -> impl Trait` in argument position._
This allows writing the following function signatures:
```rust
fn f0() -> impl Fn() -> impl Trait;
fn f3() -> &'static dyn Fn() -> impl Trait;
```
These signatures were already allowed for common traits and associated types, there is no reason why `Fn*` traits should be special in this regard.
`impl Trait` in both `f0` and `f3` means "new existential type", just like with `-> impl Iterator<Item = impl Trait>` and such.
Arrow in `impl Fn() ->` is right-associative and binds from right to left, it's tested by [this test](a819fecb8d/src/test/ui/impl-trait/impl_fn_associativity.rs).
There even is a test that `f0` compiles:
2f004d2d40/src/test/ui/impl-trait/nested_impl_trait.rs (L25-L28)
But it was changed in [PR 48084 (lines)](https://github.com/rust-lang/rust/pull/48084/files#diff-ccecca938872d65ffe8cd1c3ef1956e309fac83bcda547d8b16b89257e53a437R37) to test the opposite, probably unintentionally given [PR 48084 (lines)](https://github.com/rust-lang/rust/pull/48084/files#diff-5a02f1ed43debed1fd24f7aad72490064f795b9420f15d847bac822aa4621a1cR476-R477).
r? `@nikomatsakis`
----
This limitation is especially annoying with async code, since it forces one to write this:
```rust
trait AsyncFn3<A, B, C>: Fn(A, B, C) -> <Self as AsyncFn3<A, B, C>>::Future {
type Future: Future<Output = Self::Out>;
type Out;
}
impl<A, B, C, Fut, F> AsyncFn3<A, B, C> for F
where
F: Fn(A, B, C) -> Fut,
Fut: Future,
{
type Future = Fut;
type Out = Fut::Output;
}
fn async_closure() -> impl AsyncFn3<i32, i32, i32, Out = u32> {
|a, b, c| async move { (a + b + c) as u32 }
}
```
Instead of:
```rust
fn async_closure() -> impl Fn(i32, i32, i32) -> impl Future<Output = u32> {
|a, b, c| async move { (a + b + c) as u32 }
}
```
This patch makes it possible to use varargs for calling conventions,
which are either based on C (like efiapi) or C is based
on them (for example sysv64 and win64).
Add `#[rustc_safe_intrinsic]`
This PR adds the `#[rustc_safe_intrinsic]` attribute as mentionned on Zulip. The goal of this attribute is to avoid keeping a list of symbols as the source for stable intrinsics, and instead rely on an attribute. This is similar to `#[rustc_const_stable]` and `#[rustc_const_unstable]`, which among other things, are used to mark the constness of intrinsic functions.
Rollup of 8 pull requests
Successful merges:
- #100747 (Add long description and test for E0311)
- #102232 (Stabilize bench_black_box)
- #102288 (Suggest unwrapping `???<T>` if a method cannot be found on it but is present on `T`.)
- #102338 (Deny associated type bindings within associated type bindings)
- #102347 (Unescaping cleanups)
- #102348 (Tweak `FulfillProcessor`.)
- #102378 (Use already resolved `self_ty` in `confirm_fn_pointer_candidate`)
- #102380 (rustdoc: remove redundant mobile `.source > .sidebar` CSS)
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
PR #101224 added support for async fn in trait desuraging behind the
return_position_impl_trait_in_trait feature.
Split this out so that it's behind its own feature gate, since async fn
in trait doesn't need to follow the same stabilization schedule.
FIX - ambiguous Diagnostic link in docs
UPDATE - rename diagnostic_items to IntoDiagnostic and AddToDiagnostic
[Gardening] FIX - formatting via `x fmt`
FIX - rebase conflicts. NOTE: Confirm wheather or not we want to handle TargetDataLayoutErrorsWrapper this way
DELETE - unneeded allow attributes in Handler method
FIX - broken test
FIX - Rebase conflict
UPDATE - rename residual _SessionDiagnostic and fix LintDiag link
change AccessLevels representation
Part of RFC (https://github.com/rust-lang/rust/issues/48054). This patch implements effective visibility table with basic methods and change AccessLevels table representation according to it.
r? ``@petrochenkov``
Implement simd_as for pointers
Expands `simd_as` (and `simd_cast`) to handle pointer-to-pointer, pointer-to-integer, and integer-to-pointer conversions.
cc ``@programmerjake`` ``@thomcc``
Initial implementation of dyn*
This PR adds extremely basic and incomplete support for [dyn*](https://smallcultfollowing.com/babysteps//blog/2022/03/29/dyn-can-we-make-dyn-sized/). The goal is to get something in tree behind a flag to make collaboration easier, and also to make sure the implementation so far is not unreasonable. This PR does quite a few things:
* Introduce `dyn_star` feature flag
* Adds parsing for `dyn* Trait` types
* Defines `dyn* Trait` as a sized type
* Adds support for explicit casts, like `42usize as dyn* Debug`
* Including const evaluation of such casts
* Adds codegen for drop glue so things are cleaned up properly when a `dyn* Trait` object goes out of scope
* Adds codegen for method calls, at least for methods that take `&self`
Quite a bit is still missing, but this gives us a starting point. Note that this is never intended to become stable surface syntax for Rust, but rather `dyn*` is planned to be used as an implementation detail for async functions in dyn traits.
Joint work with `@nikomatsakis` and `@compiler-errors.`
r? `@bjorn3`
Use `DisplayBuffer` for socket addresses.
Continuation of https://github.com/rust-lang/rust/pull/100625 for socket addresses.
Renames `net::addr` to `net::addr::socket`, `net::ip` to `net::addr::ip` and `net::ip::display_buffer::IpDisplayBuffer` to `net::addr::display_buffer::DisplayBuffer`.
ssa: implement `#[collapse_debuginfo]`
cc #39153rust-lang/compiler-team#386
Debuginfo line information for macro invocations are collapsed by default - line information are replaced by the line of the outermost expansion site. Using `-Zdebug-macros` disables this behaviour.
When the `collapse_debuginfo` feature is enabled, the default behaviour is reversed so that debuginfo is not collapsed by default. In addition, the `#[collapse_debuginfo]` attribute is available and can be applied to macro definitions which will then have their line information collapsed.
r? rust-lang/wg-debugging
The primary purpose of this commit is to introduce the
dyn_star flag so we can begin experimenting with implementation.
In order to have something to do in the feature gate test, we also add
parser support for `dyn* Trait` objects. These are currently treated
just like `dyn Trait` objects, but this will change in the future.
Note that for now `dyn* Trait` is experimental syntax to enable
implementing some of the machinery needed for async fn in dyn traits
without fully supporting the feature.
The `<*const T>::guaranteed_*` methods now return an option for the unknown case
cc https://github.com/rust-lang/rust/issues/53020#issuecomment-1236932443
I chose `0` for "not equal" and `1` for "equal" and left `2` for the unknown case so backends can just forward to raw pointer equality and it works ✨
r? `@fee1-dead` or `@lcnr`
cc `@rust-lang/wg-const-eval`
Debuginfo line information for macro invocations are collapsed by
default - line information are replaced by the line of the outermost
expansion site. Using `-Zdebug-macros` disables this behaviour.
When the `collapse_debuginfo` feature is enabled, the default behaviour
is reversed so that debuginfo is not collapsed by default. In addition,
the `#[collapse_debuginfo]` attribute is available and can be applied to
macro definitions which will then have their line information collapsed.
Signed-off-by: David Wood <david.wood@huawei.com>
Make `const_eval_select` a real intrinsic
This fixes issues where `track_caller` functions do not have nice panic
messages anymore when there is a call to the function, and uses the
MIR system to replace the call instead of dispatching via lang items.
Fixes#100696.
safe transmute: use `Assume` struct to provide analysis options
This task was left as a TODO in #92268; resolving it brings [`BikeshedIntrinsicFrom`](https://doc.rust-lang.org/nightly/core/mem/trait.BikeshedIntrinsicFrom.html) more in line with the API defined in [MCP411](https://github.com/rust-lang/compiler-team/issues/411).
**Before:**
```rust
pub unsafe trait BikeshedIntrinsicFrom<
Src,
Context,
const ASSUME_ALIGNMENT: bool,
const ASSUME_LIFETIMES: bool,
const ASSUME_VALIDITY: bool,
const ASSUME_VISIBILITY: bool,
> where
Src: ?Sized,
{}
```
**After:**
```rust
pub unsafe trait BikeshedIntrinsicFrom<Src, Context, const ASSUME: Assume = { Assume::NOTHING }>
where
Src: ?Sized,
{}
```
`Assume::visibility` has also been renamed to `Assume::safety`, as library safety invariants are what's actually being assumed; visibility is just the mechanism by which it is currently checked (and that may change).
r? `@oli-obk`
---
Related:
- https://github.com/rust-lang/compiler-team/issues/411
- https://github.com/rust-lang/rust/issues/99571
