This commit does the following.
- Renames `collect_tokens_trailing_token` as `collect_tokens`, because
(a) it's annoying long, and (b) the `_trailing_token` bit is less
accurate now that its types have changed.
- In `collect_tokens`, adds a `Option<CollectPos>` argument and a
`UsePreAttrPos` in the return type of `f`. These are used in
`parse_expr_force_collect` (for vanilla expressions) and in
`parse_stmt_without_recovery` (for two different cases of expression
statements). Together these ensure are enough to fix all the problems
with token collection and assoc expressions. The changes to the
`stringify.rs` test demonstrate some of these.
- Adds a new test. The code in this test was causing an assertion
failure prior to this commit, due to an invalid `NodeRange`.
The extra complexity is annoying, but necessary to fix the existing
problems.
Fix projections when parent capture is by-ref but child capture is by-value in the `ByMoveBody` pass
This fixes a somewhat strange bug where we build the incorrect MIR in #129074. This one is weird, but I don't expect it to actually matter in practice since it almost certainly results in a move error in borrowck. However, let's not ICE.
Given the code:
```
#![feature(async_closure)]
// NOT copy.
struct Ty;
fn hello(x: &Ty) {
let c = async || {
*x;
//~^ ERROR cannot move out of `*x` which is behind a shared reference
};
}
fn main() {}
```
The parent coroutine-closure captures `x: &Ty` by-ref, resulting in an upvar of `&&Ty`. The child coroutine captures `x` by-value, resulting in an upvar of `&Ty`. When constructing the by-move body for the coroutine-closure, we weren't applying an additional deref projection to convert the parent capture into the child capture, resulting in an type error in assignment, which is a validation ICE.
As I said above, this only occurs (AFAICT) in code that eventually results in an error, because it is only triggered by HIR that attempts to move a non-copy value out of a ref. This doesn't occur if `Ty` is `Copy`, since we'd instead capture `x` by-ref in the child coroutine.
Fixes#129074
Infer async closure args from `Fn` bound even if there is no corresponding `Future` bound on return
In #127482, I implemented the functionality to infer an async closure signature when passed into a function that has `Fn` + `Future` where clauses that look like:
```
fn whatever(callback: F)
where
F: Fn(Arg) -> Fut,
Fut: Future<Output = Out>,
```
However, #127781 demonstrates that this is still incomplete to address the cases users care about. So let's not bail when we fail to find a `Future` bound, and try our best to just use the args from the `Fn` bound if we find it. This is *fine* since most users of closures only really care about the *argument* types for inference guidance, since we require the receiver of a `.` method call to be known in order to probe methods.
When I experimented with programmatically rewriting `|| async {}` to `async || {}` in #127827, this also seems to have fixed ~5000 regressions (probably all coming from usages `TryFuture`/`TryStream` from futures-rs): the [before](https://github.com/rust-lang/rust/pull/127827#issuecomment-2254061733) and [after](https://github.com/rust-lang/rust/pull/127827#issuecomment-2255470176) crater runs.
Fixes#127781.
Unconditionally allow shadow call-stack sanitizer for AArch64
It is possible to do so whenever `-Z fixed-x18` is applied.
cc ``@Darksonn`` for context
The reasoning is that, as soon as reservation on `x18` is forced through the flag `fixed-x18`, on AArch64 the option to instrument with [Shadow Call Stack sanitizer](https://clang.llvm.org/docs/ShadowCallStack.html) is then applicable regardless of the target configuration.
At the every least, we would like to relax the restriction on specifically `aarch64-unknonw-none`. For this option, we can include a documentation change saying that users of compiled objects need to ensure that they are linked to runtime with Shadow Call Stack instrumentation support.
Related: #121972
derive(SmartPointer): register helper attributes
Fix#128888
This PR enables built-in macros to register helper attributes, if any, to support correct name resolution in the correct lexical scope under the macros.
Also, `#[pointee]` is moved into the scope under `derive(SmartPointer)`.
cc `@Darksonn` `@davidtwco`
CommandExt::before_exec: deprecate safety in edition 2024
Similar to `set_var`, we had to find out after 1.0 was released that `before_exec` should have been unsafe. We partially rectified this by deprecating that function a long time ago, but since https://github.com/rust-lang/rust/pull/124636 we have the ability to also deprecate the safety of the old function and make it a *hard error* to call the old function outside `unsafe` in the next edition. So just in case anyone still uses the old function, let's ensure this can't be ignored when moving code to the new edition.
Cc `@rust-lang/libs-api`
Tracking:
- https://github.com/rust-lang/rust/issues/124866
Record the correct target type when coercing fn items/closures to pointers
Self-explanatory. We were previously not recording the *target* type of a coercion as the output of an adjustment. This should remedy that.
We must also modify the function pointer casts in MIR typeck to use subtyping, since those broke since #118247.
r? lcnr
Explicitly specify type parameter on FromResidual for Option and ControlFlow.
~~Remove type parameter default `R = <Self as Try>::Residual` from `FromResidual`~~ _Specify default type parameter on `FromResidual` impls in the stdlib_ to work around https://github.com/rust-lang/rust/issues/99940 / https://github.com/rust-lang/rust/issues/87350 ~~as mentioned in https://github.com/rust-lang/rust/issues/84277#issuecomment-1773259264~~.
This does not completely fix the issue, but works around it for `Option` and `ControlFlow` specifically (`Result` does not have the issue since it already did not use the default parameter of `FromResidual`).
~~(Does this need an ACP or similar?)~~ ~~This probably needs at least an FCP since it changes the API described in [the RFC](https://github.com/rust-lang/rfcs/pull/3058). Not sure if T-lang, T-libs-api, T-libs, or some combination (The tracking issue is tagged T-lang, T-libs-api).~~ This probably doesn't need T-lang input, since it is not changing the API of `FromResidual` from the RFC? Maybe needs T-libs-api FCP?
Rollup of 7 pull requests
Successful merges:
- #122884 (Optimize integer `pow` by removing the exit branch)
- #127857 (Allow to customize `// TODO:` comment for deprecated safe autofix)
- #129034 (Add `#[must_use]` attribute to `Coroutine` trait)
- #129049 (compiletest: Don't panic on unknown JSON-like output lines)
- #129050 (Emit a warning instead of an error if `--generate-link-to-definition` is used with other output formats than HTML)
- #129056 (Fix one usage of target triple in bootstrap)
- #129058 (Add mw back to review rotation)
r? `@ghost`
`@rustbot` modify labels: rollup
Remove a no-longer-true assert
Fixes https://github.com/rust-lang/rust/issues/129009
The assert was simply no longer true. I thought my test suite was thorough but I had not noticed these `let`-specific diagnostics codepaths.
r? `@compiler-errors`
Add `#[must_use]` attribute to `Coroutine` trait
[Coroutines tracking issue](https://github.com/rust-lang/rust/issues/43122)
Like closures (`FnOnce`, `AsyncFn`, etc.), coroutines are lazy and do nothing unless called (resumed). Closure traits like `FnOnce` have `#[must_use = "closures are lazy and do nothing unless called"]` to catch likely bugs for users of APIs that produce them. This PR adds such a `#[must_use]` attribute to `trait Coroutine`.
Allow to customize `// TODO:` comment for deprecated safe autofix
Relevant for the deprecation of `CommandExt::before_exit` in #125970.
Tracking:
- #124866
CFI: Move CFI ui tests to cfi directory
Move the CFI ui tests to the cfi directory and removes the cfi prefix from tests file names similarly to how the cfi codegen tests are organized.
miri: make vtable addresses not globally unique
Miri currently gives vtables a unique global address. That's not actually matching reality though. So this PR enables Miri to generate different addresses for the same type-trait pair.
To avoid generating an unbounded number of `AllocId` (and consuming unbounded amounts of memory), we use the "salt" technique that we also already use for giving constants non-unique addresses: the cache is keyed on a "salt" value n top of the actually relevant key, and Miri picks a random salt (currently in the range `0..16`) each time it needs to choose an `AllocId` for one of these globals -- that means we'll get up to 16 different addresses for each vtable. The salt scheme is integrated into the global allocation deduplication logic in `tcx`, and also used for functions and string literals. (So this also fixes the problem that casting the same function to a fn ptr over and over will consume unbounded memory.)
r? `@saethlin`
Fixes https://github.com/rust-lang/miri/issues/3737
Store `do_not_recommend`-ness in impl header
Alternative to #128674
It's less flexible, but also less invasive. Hopefully it's also performant. I'd recommend we think separately about the design for how to gate arbitrary diagnostic attributes moving forward.
Normalize struct tail properly for `dyn` ptr-to-ptr casting in new solver
Realized that the new solver didn't handle ptr-to-ptr casting correctly.
r? lcnr
Built on #128694
Fix bug in `Parser::look_ahead`.
The special case was failing to handle invisible delimiters on one path.
Fixes (but doesn't close until beta backported) #128895.
r? `@davidtwco`
Fix `ElaborateBoxDerefs` on debug varinfo
Slightly simplifies the `ElaborateBoxDerefs` pass to fix cases where it was applying the wrong projections to debug var infos containing places that deref boxes.
From what I can tell[^1], we don't actually have any tests (or code anywhere, really) that exercise `debug x => *(...: Box<T>)`, and it's very difficult to trigger this in surface Rust, so I wrote a custom MIR test.
What happens is that the pass was turning `*(SOME_PLACE: Box<T>)` into `*(*((((SOME_PLACE).0: Unique<T>).0: NonNull<T>).0: *const T))` in debug var infos. In particular, notice the *double deref*, which was wrong.
This is the root cause of #128554, so this PR fixes#128554 as well. The reason that async closures was affected is because of the way that we compute the [`ByMove` body](https://github.com/rust-lang/rust/blob/master/compiler/rustc_mir_transform/src/coroutine/by_move_body.rs), which resulted in `*(...: Box<T>)` in debug var info. But this really has nothing to do with async closures.
[^1]: Validated by literally replacing the `if elem == PlaceElem::Deref && base_ty.is_box() { ... }` innards with a `panic!()`, which compiled all of stage2 without panicking.
Differentiate between methods and associated functions in diagnostics
Accurately refer to assoc fn without receiver as assoc fn instead of methods. Add `AssocItem::descr` method to centralize where we call methods and associated functions.
WF-check struct field types at construction site
Fixes#126272.
Fixes#127299.
Rustc of course already WF-checked the field types at the definition
site, but for error tainting of consts to work properly, there needs to
be an error emitted at the use site. Previously, with no use-site error,
we proceeded with CTFE and ran into ICEs since we are running code with
type errors.
Emitting use-site errors also brings struct-like constructors more in
line with fn-like constructors since they already emit use-site errors
for WF issues.
r? `@BoxyUwU`
Accurately refer to assoc fn without receiver as assoc fn instead of methods.
Add `AssocItem::descr` method to centralize where we call methods and associated functions.
Ensure let stmt compound assignment removal suggestion respect codepoint boundaries
Previously we would try to issue a suggestion for `let x <op>= 1`, i.e.
a compound assignment within a `let` binding, to remove the `<op>`. The
suggestion code unfortunately incorrectly assumed that the `<op>` is an
exactly-1-byte ASCII character, but this assumption is incorrect because
we also recover Unicode-confusables like `➖=` as `-=`. In this example,
the suggestion code used a `+ BytePos(1)` to calculate the span of the
`<op>` codepoint that looks like `-` but the mult-byte Unicode
look-alike would cause the suggested removal span to be inside a
multi-byte codepoint boundary, triggering a codepoint boundary
assertion.
The fix is to use `SourceMap::start_point(token_span)` which properly accounts for codepoint boundaries.
Fixes#128845.
cc #128790
r? ````@fmease````