Implement `~const Destruct` effect goal in the new solver
This also fixed a subtle bug/limitation of the `NeedsConstDrop` check. Specifically, the "`Qualif`" API basically treats const drops as totally structural, even though dropping something that has an explicit `Drop` implementation cannot be structurally decomposed. For example:
```rust
#![feature(const_trait_impl)]
#[const_trait] trait Foo {
fn foo();
}
struct Conditional<T: Foo>(T);
impl Foo for () {
fn foo() {
println!("uh oh");
}
}
impl<T> const Drop for Conditional<T> where T: ~const Foo {
fn drop(&mut self) {
T::foo();
}
}
const FOO: () = {
let _ = Conditional(());
//~^ This should error.
};
fn main() {}
```
In this example, when checking if the `Conditional(())` rvalue is const-drop, since `Conditional` has a const destructor, we would previously recurse into the `()` value and determine it has nothing to drop, which means that it is considered to *not* need a const drop -- even though dropping `Conditional(())` would mean evaluating the destructor which relies on that `T: const Foo` bound to hold!
This could be fixed alternatively by banning any const conditions on `const Drop` impls, but that really sucks -- that means that basically no *interesting* const drop impls could be written. We have the capability to totally and intuitively support the right behavior, which I've implemented here.
Stabilize the 2024 edition
This stabilizes the 2024 edition for Rust 1.85, scheduled to be released on February 20, 2025. 🎉
cc tracking issue: https://github.com/rust-lang/rust/issues/117258
There is a fair amount of follow-up work after this that I am working on (various docs, cargo, rustfmt, etc.), and this is will unblock those other changes.
Rollup of 8 pull requests
Successful merges:
- #133238 (re-export `is_loongarch_feature_detected`)
- #133288 (Support `each_ref` and `each_mut` in `[T; N]` in constant expressions.)
- #133311 (Miri subtree update)
- #133313 (Use arc4random of libc for RTEMS target)
- #133319 (Simplify `fulfill_implication`)
- #133323 (Bail in effects in old solver if self ty is ty var)
- #133330 (library: update comment around close())
- #133337 (Fix typo in `std:🧵:Scope::spawn` documentation.)
r? `@ghost`
`@rustbot` modify labels: rollup
Bail in effects in old solver if self ty is ty var
Otherwise when we try to check something like `?t: ~const Trait` we'll immediately stick it to the first param-env candidate, lol.
r? lcnr
Support `each_ref` and `each_mut` in `[T; N]` in constant expressions.
Tracking issue: #133289
The methods `<[T; N]>::each_ref` and `<[T; N]>::each_mut` can easily be reimplemented to allow marking them with the `const` specifier.
This specific implementation takes a different approach than the original as to avoid using iterators (which are illegal in constant expressions).
Stabilize `Ipv6Addr::is_unique_local` and `Ipv6Addr::is_unicast_link_local`
Make `Ipv6Addr::is_unique_local` and `Ipv6Addr::is_unicast_link_local` stable (+const).
Newly stable API:
```rust
impl Ipv6Addr {
// Newly stable under `ipv6_is_unique_local`
const fn is_unique_local(&self) -> bool;
// Newly stable under `ipv6_is_unique_local`
const fn is_unicast_link_local(&self) -> bool;
}
```
These stabilise a subset of the following tracking issue:
- #27709
I have looked and could not find any issues with `is_unique_local` and `is_unicast_link_local`. There is a well received comment calling for stabilisation of the latter function.
Both functions are well defined and consistent with implementations in other languages:
- [Go](https://cs.opensource.google/go/go/+/refs/tags/go1.23.0:src/net/netip/netip.go;l=518)
- [Python](e9d1bf353c/Lib/ipaddress.py (L2319-L2321))
- [Ruby (unique local)](https://ruby-doc.org/stdlib-2.5.1/libdoc/ipaddr/rdoc/IPAddr.html#private-3F-source)
- [Ruby (unicast link local)](https://ruby-doc.org/stdlib-2.5.1/libdoc/ipaddr/rdoc/IPAddr.html#link_local-3F-source)
cc implementor `@little-dude`
(I can't find the original PR for `is_unqiue_local`)
r? libs-api
`@rustbot` label +T-libs-api +needs-fcp
[AIX] change system dynamic library format
Historically on AIX, almost all dynamic libraries are distributed in `.a` Big Archive Format which can consists of both static and shared objects in the same archive (e.g. `libc++abi.a(libc++abi.so.1)`). During the initial porting process, the dynamic libraries are kept as `.a` to simplify the migration, but semantically having an XCOFF object under the archive extension is wrong. For crate type `cdylib` we want to be able to distribute the libraries as archives as well.
We are migrating to archives with the following format:
```
$ ar -t lib<name>.a
lib<name>.so
```
where each archive contains a single member that is a shared XCOFF object that can be loaded.
Don't exclude relnotes from `needs-triage` label
So initially we *didn't* exclude `needs-triage` label, then we did exclude them in #132825 as sometimes the `needs-triage` is redundant. However, I think they are probably worth double-checking because often some of the labels are only accurate/relevant for the *implementation* PR, but not for the purposes of the relnotes tracking issue. Furthermore, sometimes relevant team labels can be removed. So to make it less likely for relnotes to slip through, I think we should still label relnotes-tracking-issues with `needs-triage`.
cc https://rust-lang.zulipchat.com/#narrow/channel/241545-t-release/topic/Please.20CC.20lang
r? release
Fix closure arg extraction in `extract_callable_info`, generalize it to async closures
* Fix argument extraction in `extract_callable_info`
* FIx `extract_callable_info` to work for async closures
* Remove redundant `is_fn_ty` which is just a less general `extract_callable_info`
* More precisely name what is being called (i.e. call it a "closure" not a "function")
Review this without whitespace -- I ended up reformatting `extract_callable_info` because some pesky `//` comments were keeping the let-chains from being formatted.
Add visits to nodes that already have flat_maps in ast::MutVisitor
This PR aims to add `visit_` methods for every node that has a `flat_map_` in MutVisitor, giving implementers free choice over overriding `flat_map` for 1-to-n conversions or `visit` for a 1-to-1.
There is one major problem: `flat_map_stmt`.
While all other default implementations of `flat_map`s are 1-to-1 conversion, as they either only call visits or a internal 1-to-many conversions are natural, `flat_map_stmt` doesn't follow this pattern.
`flat_map_stmt`'s default implementation is a 1-to-n conversion that panics if n > 1 (effectively being a 1-to-[0;1]). This means that it cannot be used as is for a default `visit_stmt`, which would be required to be a 1-to-1.
Implementing `visit_stmt` without runtime checks would require it to reach over a potential `flat_map_item` or `filter_map_expr` overrides and call for their `visit` counterparts directly.
Other than that, if we want to keep the behavior of `flat_map_stmt` it cannot call `visit_stmt` internally.
To me, it seems reasonable to make all default implementations 1-to-1 conversions and let implementers handle `visit_stmt` if they need it, but I don't know if calling `visit` directly when a 1-to-1 is required is ok or not.
related to #128974 & #127615
r? ``@petrochenkov``
Store resolution for self and crate root module segments
Let's make sure to record the segment resolution for `self::`, `crate::` and `$crate::`.
I'm actually somewhat surprised that the only diagnostic that uses this is the one that errors on invalid generics on a module segment... but seems strictly more correct regardless, and there may be other diagnostics using these segments resolutions that just haven't been tested for `self`. Also includes a drive-by on `report_prohibit_generics_error`.
Emscripten: link with -sWASM_BIGINT
When linking an executable without dynamic linking, this is a pure improvement. It significantly reduces code size and avoids a lot of buggy behaviors. It is supported in all browsers for many years and in all maintained versions of Node.
It does change the ABI, so people who are dynamically linking with a library or executable that uses the old ABI may need to turn it off. It can be disabled if needed by passing `-Clink-arg -sWASM_BIGINT=0` to `rustc`. But few people will want to turn it off.
Note this includes a libc bump to 0.2.162!
