(Re-)return adjustment target if adjust kind is never-to-any
This PR fixes#134162 where we ICE'd on
```rs
fn main() {
struct X;
let _ = [X] == [panic!(); 2];
}
```
In https://github.com/rust-lang/rust/pull/121208#discussion_r1494187622, there was a change
```diff
- if let Some(adjustments) = self.typeck_results.borrow().adjustments().get(expr.hir_id) {
- let reported = self.dcx().span_delayed_bug(
- expr.span,
- "expression with never type wound up being adjusted",
- );
- return if let [Adjustment { kind: Adjust::NeverToAny, target }] = &adjustments[..] {
- target.to_owned()
- } else {
- Ty::new_error(self.tcx(), reported)
- };
- }
+ if let Some(_) = self.typeck_results.borrow().adjustments().get(expr.hir_id) {
+ self.dcx()
+ .span_bug(expr.span, "expression with never type wound up being adjusted");
+ }
```
It turned out returning the adjustment target if the adjustment kind is `NeverToAny` is necessary, as otherwise we will go through a series of `delay_bug`s and eventually find that we constructed a `TyKind::Error` without having actually emitted an error.
This PR addresses that by re-returning the adjustment target if the adjustment kind is `NeverToAny`, partially reverting this change from #121208.
This PR has two commits:
1. The first commit adds a regression test for #134162, which will ICE (on stable 1.83.0, beta and nightly 2024-12-13).
2. The second commit is the partial revert, which will fix the ICE.
cc `@nnethercote` FYI as this is related to #121208 changes. The changes from #121208 exposed that we lacked test coverage for the code pattern reported in #134162.
Make some types and methods related to Polonius + Miri public
We have a tool, [Aquascope](https://github.com/cognitive-engineering-lab/aquascope/), which uses Polonius and Miri to visualize the compile-time and run-time semantics of a Rust program. Changes in the last few months to both APIs have hidden away details we depend upon. This PR re-exposes some of those details, specifically:
**Polonius:**
- `BorrowSet` and `BorrowData` are added to `rustc_borrowck::consumers`, and their fields are made `pub` instead of `pub(crate)`. We need this to interpret the `BorrowIndex`es generated by Polonius.
- `BorrowSet::build` is now `pub`. We need this because the borrowck API doesn't provide access to the `BorrowSet` constructed during checking.
- `PoloniusRegionVid` is added to `rustc_borrowck::consumers`. We need this because it's also contained in the Polonius facts.
**Miri:**
- `InterpCx::local_to_op` is now a special case of `local_at_frame_to_op`, which allows querying locals in any frame. We need this because we walk the whole stack at each step to collect the state of memory.
- `InterpCx::layout_of_local` is now `pub`. We need this because we need to know the layout of every local at each step.
If these changes go against some design goal for keeping certain types private, please let me know so we can hash out a better solution. Additionally, if there's a better way to document that it's important that certain types stay public, also let me know. For example, `BorrowSet` was previously public but was hidden in 6676cec, breaking our build.
cc ```@RalfJung``` ```@nnethercote``` ```@gavinleroy```
Update linux_musl base to dynamically link the crt by default
However, don't change the behavior of any existing targets at this time. For targets that used the old default, explicitly set `crt_static_default = true`.
This makes it easier for new targets to use the correct defaults while leaving the changing of individual targets to future PRs.
Related to https://github.com/rust-lang/compiler-team/issues/422
Add external macros specific diagnostics for check-cfg
This PR adds specific check-cfg diagnostics for unexpected cfg in external macros.
As well as hiding the some of the Cargo specific help/suggestions as they distraction for external macros and are generally not the right solution.
Follow-up to #132577
`@rustbot` label +L-unexpected_cfgs
r? compiler
Rollup of 6 pull requests
Successful merges:
- #132150 (Fix powerpc64 big-endian FreeBSD ABI)
- #133942 (Clarify how to use `black_box()`)
- #134081 (Try to evaluate constants in legacy mangling)
- #134192 (Remove `Lexer`'s dependency on `Parser`.)
- #134208 (coverage: Tidy up creation of covmap and covfun records)
- #134211 (On Neutrino QNX, reduce the need to set archiver via environment variables)
r? `@ghost`
`@rustbot` modify labels: rollup
(Re-)Implement `impl_trait_in_bindings`
This reimplements the `impl_trait_in_bindings` feature for local bindings.
"`impl Trait` in bindings" serve as a form of *trait* ascription, where the type basically functions as an infer var but additionally registering the `impl Trait`'s trait bounds for the infer type. These trait bounds can be used to enforce that predicates hold, and can guide inference (e.g. for closure signature inference):
```rust
let _: impl Fn(&u8) -> &u8 = |x| x;
```
They are implemented as an additional set of bounds that are registered when the type is lowered during typeck, and then these bounds are tied to a given `CanonicalUserTypeAscription` for borrowck. We enforce these `CanonicalUserTypeAscription` bounds during borrowck to make sure that the `impl Trait` types are sensitive to lifetimes:
```rust
trait Static: 'static {}
impl<T> Static for T where T: 'static {}
let local = 1;
let x: impl Static = &local;
//~^ ERROR `local` does not live long enough
```
r? oli-obk
cc #63065
---
Why can't we just use TAIT inference or something? Well, TAITs in bodies have the problem that they cannot reference lifetimes local to a body. For example:
```rust
type TAIT = impl Display;
let local = 0;
let x: TAIT = &local;
//~^ ERROR `local` does not live long enough
```
That's because TAITs requires us to do *opaque type inference* which is pretty strict, since we need to remap all of the lifetimes of the hidden type to universal regions. This is simply not possible here.
---
I consider this part of the "impl trait everywhere" experiment. I'm not certain if this needs yet another lang team experiment.
Without doing so, we'll run into a series of delayed bugs then find that
we have a `TyKind::Error` constructed yet fail to emit an error.
This partially reverts a change in
<https://github.com/rust-lang/rust/pull/121208> related to never type
adjustments in expr typecheck errors.
Rollup of 8 pull requests
Successful merges:
- #134252 (Fix `Path::is_absolute` on Hermit)
- #134254 (Fix building `std` for Hermit after `c_char` change)
- #134255 (Update includes in `/library/core/src/error.rs`.)
- #134261 (Document the symbol Visibility enum)
- #134262 (Arbitrary self types v2: adjust diagnostic.)
- #134265 (Rename `ty_def_id` so people will stop using it by accident)
- #134271 (Arbitrary self types v2: better feature gate test)
- #134274 (Add check-pass test for `&raw`)
r? `@ghost`
`@rustbot` modify labels: rollup
coverage: Tidy up creation of covmap and covfun records
This is a small follow-up to #134163 that mostly just inlines and renames some variables, and adds a few comments.
It also slightly defers the creation of the LLVM value that holds the filename table, to just before the value is needed.
---
try-job: x86_64-mingw-2
try-job: dist-x86_64-linux
Remove `Lexer`'s dependency on `Parser`.
Lexing precedes parsing, as you'd expect: `Lexer` creates a `TokenStream` and `Parser` then parses that `TokenStream`.
But, in a horrendous violation of layering abstractions and common sense, `Lexer` depends on `Parser`! The `Lexer::unclosed_delim_err` method does some error recovery that relies on creating a `Parser` to do some post-processing of the `TokenStream` that the `Lexer` just created.
This commit just removes `unclosed_delim_err`. This change removes `Lexer`'s dependency on `Parser`, and also means that `lex_token_tree`'s return value can have a more typical form.
The cost is slightly worse error messages in two obscure cases, as shown in these tests:
- tests/ui/parser/brace-in-let-chain.rs: there is slightly less explanation in this case involving an extra `{`.
- tests/ui/parser/diff-markers/unclosed-delims{,-in-macro}.rs: the diff marker detection is no longer supported (because that detection is implemented in the parser).
In my opinion this cost is outweighed by the magnitude of the code cleanup.
r? ```````@chenyukang```````
Try to evaluate constants in legacy mangling
Best reviewed commit by commit.
It seems kind of odd to treat literals differently from unevaluated free constants. So let's evaluate those constants and only fall back to `_` rendering if that fails to result in an integral constant
Rename `ty_def_id` so people will stop using it by accident
This function is just for cycle detection, but people keep using it because they think it's the right way of getting the def id from a `Ty` (and I can't blame them necessarily).
Arbitrary self types v2: adjust diagnostic.
The recently landed PR #132961 to adjust arbitrary self types was a bit overenthusiastic, advising folks to use the new Receiver trait even before it's been stabilized. Revert to the older wording of the lint in such cases.
Tracking issue #44874
r? ``@wesleywiser``
A bunch of cleanups (part 2)
Just like https://github.com/rust-lang/rust/pull/133567 these were all found while looking at the respective code, but are not blocking any other changes I want to make in the short term.
rustc_borrowck: Stop suggesting the invalid syntax `&mut raw const`
A legitimate suggestion would be to change from
&raw const val
to
&raw mut val
But until we have figured out how to make that happen we should at least
stop suggesting invalid syntax.
I recommend review commit-by-commit.
Part of #127562
Tweak multispan rendering to reduce output length
Consider comments and bare delimiters the same as an "empty line" for purposes of hiding rendered code output of long multispans. This results in more aggressive shortening of rendered output without losing too much context, specially in `*.stderr` tests that have "hidden" comments. We do that check not only on the first 4 lines of the multispan, but now also on the previous to last line as well.
Rollup of 7 pull requests
Successful merges:
- #133900 (Advent of `tests/ui` (misc cleanups and improvements) [1/N])
- #133937 (Keep track of parse errors in `mod`s and don't emit resolve errors for paths involving them)
- #133938 (`rustc_mir_dataflow` cleanups, including some renamings)
- #134058 (interpret: reduce usage of TypingEnv::fully_monomorphized)
- #134130 (Stop using driver queries in the public API)
- #134140 (Add AST support for unsafe binders)
- #134229 (Fix typos in docs on provenance)
r? `@ghost`
`@rustbot` modify labels: rollup
When we recover from a pattern parse error, or a pattern uses `..`, we keep track of that and affect resolution error for missing bindings that could have been provided by that pattern. We differentiate between `..` and parse recovery. We silence resolution errors likely caused by the pattern parse error.
```
error[E0425]: cannot find value `title` in this scope
--> $DIR/struct-pattern-with-missing-fields-resolve-error.rs:19:30
|
LL | println!("[{}]({})", title, url);
| ^^^^^ not found in this scope
|
note: `Website` has a field `title` which could have been included in this pattern, but it wasn't
--> $DIR/struct-pattern-with-missing-fields-resolve-error.rs:17:12
|
LL | / struct Website {
LL | | url: String,
LL | | title: Option<String> ,
| | ----- defined here
LL | | }
| |_-
...
LL | if let Website { url, .. } = website {
| ^^^^^^^^^^^^^^^^^^^ this pattern doesn't include `title`, which is available in `Website`
```
Fix#74863.
forbid toggling x87 and fpregs on hard-float targets
Part of https://github.com/rust-lang/rust/issues/116344, follow-up to https://github.com/rust-lang/rust/pull/129884:
The `x87` target feature on x86 and the `fpregs` target feature on ARM must not be disabled on a hardfloat target, as that would change the float ABI. However, *enabling* `fpregs` on ARM is [explicitly requested](https://github.com/rust-lang/rust/issues/130988) as it seems to be useful. Therefore, we need to refine the distinction of "forbidden" target features and "allowed" target features: all (un)stable target features can determine on a per-target basis whether they should be allowed to be toggled or not. `fpregs` then checks whether the current target has the `soft-float` feature, and if yes, `fpregs` is permitted -- otherwise, it is not. (Same for `x87` on x86).
Also fixes https://github.com/rust-lang/rust/issues/132351. Since `fpregs` and `x87` can be enabled on some builds and disabled on others, it would make sense that one can query it via `cfg`. Therefore, I made them behave in `cfg` like any other unstable target feature.
The first commit prepares the infrastructure, but does not change behavior. The second commit then wires up `fpregs` and `x87` with that new infrastructure.
r? `@workingjubilee`
Add AST support for unsafe binders
I'm splitting up #130514 into pieces. It's impossible for me to keep up with a huge PR like that. I'll land type system support for this next, probably w/o MIR lowering, which will come later.
r? `@oli-obk`
cc `@BoxyUwU` and `@lcnr` who also may want to look at this, though this PR doesn't do too much yet
Stop using driver queries in the public API
Follow up to https://github.com/rust-lang/rust/pull/132410 and https://github.com/rust-lang/rust/pull/133567
The next PR will completely get rid of driver queries. That PR will also contains some non-trivial refactorings enabled by no longer needing to support entering TyCtxt multiple times after it is constructed. The changes in the current PR have been split out to make it easier to review the api changes and to reduce the size of the next PR to review.
## Custom driver breaking change
The `after_crate_root_parsing` and `after_expansion` callbacks now accept `ast::Crate` and `TyCtxt` respectively rather than `Queries`. The only safe query in `Queries` to call inside these callbacks are `parse()` and `global_ctxt()` respectively which allows you to access the `ast::Crate` and `TyCtxt` either way. To fix your custom driver, replace the `queries: &'tcx Queries<'tcx>` argument with `crate_: ast::Crate` and `tcx: TyCtxt<'tcx>` respectively and for `after_expansion` remove your `queries.global_ctxt().unwrap().enter(|tcx| { ... })` call and only keep the contents of the closure.
Keep track of parse errors in `mod`s and don't emit resolve errors for paths involving them
When we expand a `mod foo;` and parse `foo.rs`, we now track whether that file had an unrecovered parse error that reached the end of the file. If so, we keep that information around in the HIR and mark its `DefId` in the `Resolver`. When resolving a path like `foo::bar`, we do not emit any errors for "`bar` not found in `foo`", as we know that the parse error might have caused `bar` to not be parsed and accounted for.
When this happens in an existing project, every path referencing `foo` would be an irrelevant compile error. Instead, we now skip emitting anything until `foo.rs` is fixed. Tellingly enough, we didn't have any test for errors caused by expansion of `mod`s with parse errors.
Fix https://github.com/rust-lang/rust/issues/97734.
Move impl constness into impl trait header
This PR is kind of the opposite of the rejected https://github.com/rust-lang/rust/pull/134114
Instead of moving more things into the `constness` query, we want to keep them where their corresponding hir nodes are lowered. So I gave this a spin for impls, which have an obvious place to be (the impl trait header). And surprisingly it's also a perf improvement (likely just slightly better query & cache usage).
The issue was that removing anything from the `constness` query makes it just return `NotConst`, which is wrong. So I had to change it to `bug!` out if used wrongly, and only then remove the impl blocks from the `constness` query. I think this change is good in general, because it makes using `constness` more robust (as can be seen by how few sites that had to be changed, so it was almost solely used specifically for the purpose of asking for functions' constness). The main thing where this change was not great was in clippy, which was using the `constness` query as a general DefId -> constness map. I added a `DefKind` filter in front of that. If it becomes a more common pattern we can always move that helper into rustc.
The recently landed PR to adjust arbitrary self types was a bit
overenthusiastic, advising folks to use the new Receiver trait even
before it's been stabilized. Revert to the older wording of the lint in
such cases.
A legitimate suggestion would be to change from
&raw const val
to
&raw mut val
But until we have figured out how to make that happen we should at least
stop suggesting invalid syntax.
This is the only trait specializable outside of the standard library.
Before stabilizing specialization we will probably want to remove
support for this. It was originally made specializable to allow a more
efficient ToString in libproc_macro back when this way the only way to
get any data out of a TokenStream. We now support getting individual
tokens, so proc macros no longer need to call it as often.