Explicitly handle all nodes in `generics_of` when computing parent
If we, for example, forget to feed `generics_of` then it'll silently fall back to empty generics. Make this a bit more explicit.
Make the enum check work for negative discriminants
The discriminant check was not working correctly for negative numbers. This change fixes that by masking out the relevant bits correctly.
Fixesrust-lang/rust#143218.
Rollup of 11 pull requests
Successful merges:
- rust-lang/rust#131923 (Derive `Copy` and `Hash` for `IntErrorKind`)
- rust-lang/rust#138340 (Remove some unsized tuple impls now that we don't support unsizing tuples anymore)
- rust-lang/rust#141219 (Change `{Box,Arc,Rc,Weak}::into_raw` to only work with `A = Global`)
- rust-lang/rust#142212 (bootstrap: validate `rust.codegen-backends` & `target.<triple>.codegen-backends`)
- rust-lang/rust#142237 (Detect more cases of unused_parens around types)
- rust-lang/rust#142964 (Attribute rework: a parser for single attributes without arguments)
- rust-lang/rust#143070 (Rewrite `macro_rules!` parser to not use the MBE engine itself)
- rust-lang/rust#143235 (Assemble const bounds via normal item bounds in old solver too)
- rust-lang/rust#143261 (Feed `explicit_predicates_of` instead of `predicates_of`)
- rust-lang/rust#143276 (loop match: handle opaque patterns)
- rust-lang/rust#143306 (Add `track_caller` attributes to trace origin of Clippy lints)
r? `@ghost`
`@rustbot` modify labels: rollup
try-job: aarch64-apple
try-job: x86_64-msvc-1
try-job: x86_64-gnu
try-job: dist-i586-gnu-i586-i686-musl
try-job: test-various
Rollup of 9 pull requests
Successful merges:
- rust-lang/rust#141847 (Explain `TOCTOU` on the top of `std::fs`, and reference it in functions)
- rust-lang/rust#142138 (Add `Vec::into_chunks`)
- rust-lang/rust#142321 (Expose elf abi on ppc64 targets)
- rust-lang/rust#142886 (ci: aarch64-gnu: Stop skipping `panic_abort_doc_tests`)
- rust-lang/rust#143194 (fix bitcast of single-element SIMD vectors)
- rust-lang/rust#143231 (Suggest use another lifetime specifier instead of underscore lifetime)
- rust-lang/rust#143232 ([COMPILETEST-UNTANGLE 3/N] Use "directives" consistently within compiletest)
- rust-lang/rust#143258 (Don't recompute `DisambiguatorState` for every RPITIT in trait definition)
- rust-lang/rust#143274 (ci: support optional jobs)
r? `@ghost`
`@rustbot` modify labels: rollup
Add `track_caller` attributes to trace origin of Clippy lints
This allows the use of `-Z track-diagnostics` to see the origin of Clippy lints emission, as is already the case for lints coming from rustc.
Feed `explicit_predicates_of` instead of `predicates_of`
Tiny nitpick, just avoiding needing to mark the `predicates_of` query as feedable since it's derived from `explicit_predicates_of`.
Rewrite `macro_rules!` parser to not use the MBE engine itself
The `macro_rules!` parser was written to match the series of rules using the macros-by-example (MBE) engine and a hand-written equivalent of the left-hand side of a MBE macro. This was complex to read, difficult to extend, and produced confusing error messages. Because it was using the MBE engine, any parse failure would be reported as if some macro was being applied to the `macro_rules!` invocation itself; for instance, errors would talk about "macro invocation", "macro arguments", and "macro call", when they were actually about the macro *definition*.
And in practice, the `macro_rules!` parser only used the MBE engine to extract the left-hand side and right-hand side of each rule as a token tree, and then parsed the rest using a separate parser.
Rewrite it to parse the series of rules using a simple loop, instead. This makes it more extensible in the future, and improves error messages. For instance, omitting a semicolon between rules will result in "expected `;`" and "unexpected token", rather than the confusing "no rules expected this token in macro call".
This work was greatly aided by pair programming with Vincenzo Palazzo (`@vincenzopalazzo)` and Eric Holk (`@eholk).`
For review, I recommend reading the two commits separately.
Attribute rework: a parser for single attributes without arguments
Part of rust-lang/rust#131229
r? `@jdonszelmann`
I think code (with comments) speaks for itself.
The only subtlety: now `#[cold]`, `#[no_mangle]`, & `#[track_caller]` do not get thrown away when malformed (i.e. have arguments). This doesn't matter too much (I think), because an error gets emitted either way, so the compilation will not finish.
Don't recompute `DisambiguatorState` for every RPITIT in trait definition
The `associated_type_for_impl_trait_in_trait` currently needs to rerun the `RPITVisitor` for every RPITIT to compute its disambiguator.
Instead of synthesizing all of the RPITITs def ids one at a time in different queries, just synthesize them inside of the `associated_types_for_impl_traits_in_associated_fn` query. There we can just share the same `DisambiguatorState` for all the RPITITs in one function signature.
r? ``````@Zoxc`````` or ``````@oli-obk`````` cc rust-lang/rust#140453
fix bitcast of single-element SIMD vectors
in effect this reverts https://github.com/rust-lang/rust/pull/142768 and adds additional tests. That PR relaxed the conditions on an early return in an incorrect way that would create broken LLVM IR.
https://godbolt.org/z/PaaGWTv5a
```rust
#![feature(repr_simd)]
#[repr(simd)]
#[derive(Clone, Copy)]
struct S([i64; 1]);
#[no_mangle]
pub extern "C" fn single_element_simd(b: S) -> i64 {
unsafe { std::mem::transmute(b) }
}
```
at the time of writing generates this LLVM IR, where the type of the return is different from the function's return type.
```llvm
define noundef i64 ``````@single_element_simd(<1`````` x i64> %b) unnamed_addr {
start:
ret <1 x i64> %b
}
```
The test output is actually the same for the existing tests, showing that the change didn't actually matter for any tested behavior. It is probably a bit faster to do the early return, but, well, it's incorrect in general.
zullip thread: [#t-compiler > Is transmuting a `T` to `Tx1` (one-element SIMD vector) UB?](https://rust-lang.zulipchat.com/#narrow/channel/131828-t-compiler/topic/Is.20transmuting.20a.20.60T.60.20to.20.60Tx1.60.20.28one-element.20SIMD.20vector.29.20UB.3F/with/526262799)
cc ``````@sayantn``````
r? ``````@scottmcm``````
Remove let_chains unstable feature
Per https://github.com/rust-lang/rust/issues/53667#issuecomment-3016742982 (but then I also noticed rust-lang/rust#140722)
This replaces the feature gate with a parser error that says let chains require 2024.
A lot of tests were using the unstable feature. I either added edition:2024 to the test or split out the parts that require 2024.
Add new self-profiling event to cheaply aggregate query cache hit counts
Self-profile can record various types of things, some of them are not enabled, like query cache hits. Rustc currently records cache hits as "instant" measureme events, which records the thread ID, current timestamp, and constructs an individual event for each such cache hit. This is incredibly expensive, in a small hello world benchmark that just depends on serde, it makes compilation with nightly go from ~3s (with `-Zself-profile`) to ~15s (with `-Zself-profile -Zself-profile-events=default,query-cache-hit`).
We'd like to add query cache hits to rustc-perf (https://github.com/rust-lang/rustc-perf/pull/2168), but there we only need the actualy cache hit counts, not the timestamp/thread ID metadata associated with it.
This PR adds a new `query-cache-hit-count` event. Instead of generating individual instant events, it simply aggregates cache hit counts per *query invocation* (so a combination of a query and its arguments, if I understand it correctly) using an atomic counter. At the end of the compilation session, these counts are then dumped to the self-profile log using integer events (in a similar fashion as how we record artifact sizes). I suppose that we could dedup the query invocations in rustc directly, but I don't think it's really required. In local experiments with the hello world + serde case, the query invocation records generated ~30 KiB more data in the self-profile, which was ~10% increase in this case.
With this PR, the overhead of `-Zself-profile` seems to be the same as before, at least on my machine, so I also enabled query cache hit counts by default when self profiling is enabled.
We should also modify `analyzeme`, specifically [this](https://github.com/rust-lang/measureme/blob/master/analyzeme/src/analysis.rs#L139), and make it load the integer events with query cache hit counts. I can do that as a follow-up, it's not required to be done in sync with this PR, and it doesn't require changes in rustc.
CC `@cjgillot`
r? `@oli-obk`
Remove support for `dyn*` from the compiler
This PR removes support for `dyn*` (https://github.com/rust-lang/rust/issues/102425), which are a currently un-RFC'd experiment that was opened a few years ago to explore a component that we thought was necessary for AFIDT (async fn in dyn trait).
It doesn't seem like we are going to need `dyn*` types -- even in an not-exposed-to-the-user way[^1] -- for us to implement AFIDT. Given that AFIDT was the original motivating purpose of `dyn*` types, I don't really see a compelling reason to have to maintain their implementation in the compiler.
[^1]: Compared to, e.g., generators whih are an unstable building block we use to implement stable syntax like `async {}`.
We've learned quite a lot from `dyn*`, but I think at this point its current behavior leads to more questions than answers. For example, `dyn*` support today remains somewhat fragile; it ICEs in many cases where the current "normal" `dyn Trait` types rely on their unsizedness for their vtable-based implementation to be sound I wouldn't be surprised if it's unsound in other ways, though I didn't play around with it too much. See the examples below.
```rust
#![feature(dyn_star)]
trait Foo {
fn hello(self);
}
impl Foo for usize {
fn hello(self) {
println!("hello, world");
}
}
fn main() {
let x: dyn* Foo = 1usize;
x.hello();
}
```
And:
```rust
#![feature(dyn_star)]
trait Trait {
type Out where Self: Sized;
}
fn main() {
let x: <dyn* Trait as Trait>::Out;
}
```
...and probably many more problems having to do with the intersection of dyn-compatibility and `Self: Sized` bounds that I was too lazy to look into like:
* GATs
* Methods with invalid signatures
* Associated consts
Generally, `dyn*` types also end up getting in the way of working with [normal `dyn` types](https://github.com/rust-lang/rust/issues/102425#issuecomment-1712604409) to an extent that IMO outweighs the benefit of experimentation.
I recognize that there are probably other, more creative usages of `dyn*` that are orthogonal to AFIDT. However, I think any work along those lines should first have to think through some of the more fundamental interactions between `dyn*` and dyn-compatibility before we think about reimplementing them in the type system.
---
I'm planning on removing the `DynKind` enum and the `PointerLike` built-in trait from the compiler after this PR lands.
Closesrust-lang/rust#102425.
cc `@eholk` `@rust-lang/lang` `@rust-lang/types`
Closesrust-lang/rust#116979.
Closesrust-lang/rust#119694.
Closesrust-lang/rust#134591.
Closesrust-lang/rust#104800.
Rollup of 12 pull requests
Successful merges:
- rust-lang/rust#136801 (Implement `Random` for tuple)
- rust-lang/rust#141867 (Describe Future invariants more precisely)
- rust-lang/rust#142760 (docs(fs): Touch up grammar on lock api)
- rust-lang/rust#143181 (Improve testing and error messages for malformed attributes)
- rust-lang/rust#143210 (`tests/ui`: A New Order [19/N] )
- rust-lang/rust#143212 (`tests/ui`: A New Order [20/N])
- rust-lang/rust#143230 ([COMPILETEST-UNTANGLE 2/N] Make some compiletest errors/warnings/help more visually obvious)
- rust-lang/rust#143240 (Port `#[rustc_object_lifetime_default]` to the new attribute parsing …)
- rust-lang/rust#143255 (Do not enable LLD by default in the dist profile)
- rust-lang/rust#143262 (mir: Mark `Statement` and `BasicBlockData` as `#[non_exhaustive]`)
- rust-lang/rust#143269 (bootstrap: make comment more clear)
- rust-lang/rust#143279 (Remove `ItemKind::descr` method)
Failed merges:
- rust-lang/rust#143237 (Port `#[no_implicit_prelude]` to the new attribute parsing infrastructure)
r? `@ghost`
`@rustbot` modify labels: rollup
Remove `ItemKind::descr` method
Follow-up of rust-lang/rust#143234.
After this PR is merged, it will remain two `descr` methods:
* `hir::GenericArg::descr`
* `hir::AssocItemConstraintKind::descr`
For both these enums, I don't think there is the right equivalent in `hir::DefKind` so unless I missed something, we can't remove these two methods because we can't convert these enums into `hir::DefKind`.
r? `@oli-obk`
Improve testing and error messages for malformed attributes
This PR has been split into 5 commits for reviewability, I recommend reviewing them one-by-one.
This first commit introduces more tests, the other 4 commits fix 4 bugs discovered by the test.
r? `@oli-obk`
cc `@jdonszelmann`
Fixes https://github.com/rust-lang/rust/issues/143136
Start moving wf checking away from HIR
I'm trying to only access the HIR in the error path. My hope is that once we move significant portions of wfcheck off HIR that incremental will be able to cache wfcheck queries significantly better.
I think I am reaching a blocker because we normally need to provide good spans to `ObligationCause`, so that the trait solver can report good errors. In some cases I have been able to use bad spans and improve them depending on the `ObligationCauseCode` (by loading HIR in the case where we actually want to error). To scale that further we'll likely need to remove spans from the `ObligationCause` entirely (leaving it to some variants of `ObligationCauseCode` to have a span when they can't recompute the information later). Unsure this is the right approach, but we've already been using it. I will create an MCP about it, but that should not affect this PR, which is fairly limited in where it does those kind of tricks.
Especially b862d8828e is interesting here, because I think it improves spans in all cases
