Match ergonomics 2024: Implement TC's match ergonomics proposal
Under gate `ref_pat_eat_one_layer_2024_structural`. Enabling `ref_pat_eat_one_layer_2024` at the same time allows the union of what the individual gates allow. `@traviscross`
r? `@Nadrieril`
cc https://github.com/rust-lang/rust/issues/123076
`@rustbot` label A-edition-2024 A-patterns
Miri function identity hack: account for possible inlining
Having a non-lifetime generic is not the only reason a function can be duplicated. Another possibility is that the function may be eligible for cross-crate inlining. So also take into account the inlining attribute in this Miri hack for function pointer identity.
That said, `cross_crate_inlinable` will still sometimes return true even for `inline(never)` functions:
- when they are `DefKind::Ctor(..) | DefKind::Closure` -- I assume those cannot be `InlineAttr::Never` anyway?
- when `cross_crate_inline_threshold == InliningThreshold::Always`
so maybe this is still not quite the right criterion to use for function pointer identity.
cache type sizes in type-size limit visitor
This is basically https://github.com/rust-lang/rust/pull/125507#issuecomment-2206813779 as lcnr can't open the PR now.
Locally it reduces the `itertools` regression by quite a bit, to "only +50%" compared to nightly (that includes overhead from the local lack of artifact post-processing, and is just a data point to compare to the 10-20x timings without the cache).
```console
Benchmark 1: cargo +stage1 build --release
Time (mean ± σ): 2.721 s ± 0.009 s [User: 2.446 s, System: 0.325 s]
Range (min … max): 2.710 s … 2.738 s 10 runs
Benchmark 2: cargo +nightly build --release
Time (mean ± σ): 1.784 s ± 0.005 s [User: 1.540 s, System: 0.279 s]
Range (min … max): 1.778 s … 1.792 s 10 runs
Summary
cargo +nightly build --release ran
1.52 ± 0.01 times faster than cargo +stage1 build --release
```
On master, it's from 34s to the 2.7s above.
r? compiler-errors
Rollup of 9 pull requests
Successful merges:
- #123043 (Disable dead variant removal for `#[repr(C)]` enums.)
- #126405 (Migrate some rustc_builtin_macros to SessionDiagnostic)
- #127037 (Remove some duplicated tests)
- #127283 (Reject SmartPointer constructions not serving the purpose)
- #127301 (Tweak some structured suggestions to be more verbose and accurate)
- #127307 (Allow to have different types for arguments of `Rustc::remap_path_prefix`)
- #127309 (jsondocck: add `$FILE` built-in variable)
- #127314 (Trivial update on tidy bless note)
- #127319 (Remove a use of `StructuredDiag`, which is incompatible with automatic error tainting and error translations)
r? `@ghost`
`@rustbot` modify labels: rollup
Remove a use of `StructuredDiag`, which is incompatible with automatic error tainting and error translations
fixes#127219
I want to remove all of `StructuredDiag`, but it's a bit more involved as it is also used from the `ItemCtxt`, which doesn't support tainting yet.
Tweak some structured suggestions to be more verbose and accurate
Addressing some issues I found while working on #127282.
```
error: this URL is not a hyperlink
--> $DIR/auxiliary/include-str-bare-urls.md:1:11
|
LL | HEADS UP! https://example.com MUST SHOW UP IN THE STDERR FILE!
| ^^^^^^^^^^^^^^^^^^^
|
= note: bare URLs are not automatically turned into clickable links
note: the lint level is defined here
--> $DIR/include-str-bare-urls.rs:14:9
|
LL | #![deny(rustdoc::bare_urls)]
| ^^^^^^^^^^^^^^^^^^
help: use an automatic link instead
|
LL | HEADS UP! <https://example.com> MUST SHOW UP IN THE STDERR FILE!
| + +
```
```
error[E0384]: cannot assign twice to immutable variable `v`
--> $DIR/assign-imm-local-twice.rs:7:5
|
LL | v = 1;
| ----- first assignment to `v`
LL | println!("v={}", v);
LL | v = 2;
| ^^^^^ cannot assign twice to immutable variable
|
help: consider making this binding mutable
|
LL | let mut v: isize;
| +++
```
```
error[E0393]: the type parameter `Rhs` must be explicitly specified
--> $DIR/issue-22560.rs:9:23
|
LL | trait Sub<Rhs=Self> {
| ------------------- type parameter `Rhs` must be specified for this
...
LL | type Test = dyn Add + Sub;
| ^^^
|
= note: because of the default `Self` reference, type parameters must be specified on object types
help: set the type parameter to the desired type
|
LL | type Test = dyn Add + Sub<Rhs>;
| +++++
```
```
error[E0596]: cannot borrow `v` as mutable, as it is not declared as mutable
--> $DIR/issue-33819.rs:4:34
|
LL | Some(ref v) => { let a = &mut v; },
| ^^^^^^ cannot borrow as mutable
|
help: try removing `&mut` here
|
LL - Some(ref v) => { let a = &mut v; },
LL + Some(ref v) => { let a = v; },
|
```
```
help: remove the invocation before committing it to a version control system
|
LL - dbg!();
|
```
```
error[E0308]: mismatched types
--> $DIR/issue-39974.rs:1:21
|
LL | const LENGTH: f64 = 2;
| ^ expected `f64`, found integer
|
help: use a float literal
|
LL | const LENGTH: f64 = 2.0;
| ++
```
```
error[E0529]: expected an array or slice, found `Vec<i32>`
--> $DIR/match-ergonomics.rs:8:9
|
LL | [&v] => {},
| ^^^^ pattern cannot match with input type `Vec<i32>`
|
help: consider slicing here
|
LL | match x[..] {
| ++++
```
```
error[E0609]: no field `0` on type `[u32; 1]`
--> $DIR/parenthesized-deref-suggestion.rs:10:21
|
LL | (x as [u32; 1]).0;
| ^ unknown field
|
help: instead of using tuple indexing, use array indexing
|
LL | (x as [u32; 1])[0];
| ~ +
```
Reject SmartPointer constructions not serving the purpose
Tracking issue: #123430
With this PR we will reject a row of malformed `SmartPointer` implementor candidates.
cc `@Darksonn` `@davidtwco` for context.
Migrate some rustc_builtin_macros to SessionDiagnostic
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Part of https://github.com/rust-lang/rust/issues/100717.
pick up abandoned pr: #101935
`@rustbot` label +A-translation
Disable dead variant removal for `#[repr(C)]` enums.
This prevents removing dead branches from a `#[repr(C)]` enum (they now get discriminants allocated as if they were inhabited).
Implementation notes: ABI of something like
```rust
#[repr(C)]
enum Foo {
Foo(!),
}
```
is still `Uninhabited`, but its layout is now computed as if all the branches were inhabited.
This seemed to me like a proper way to do it, especially given that ABI sanity check explicitly asserts that type-level uninhabitedness implies ABI uninhabitedness.
This probably needs some sort of FCP (given that it changes `#[repr(C)]` layout, which is a stable guarantee), but I’m not sure how to call for one or which team is the most relevant.
See https://github.com/rust-lang/unsafe-code-guidelines/issues/500.
Stop using specialization in rustc_index and rustc_borrowck
For rustc_borrowck the version with specialization isn't much more readable anyway IMO. For rustc_index it probably doesn't affect perf in any noticeable way anyway.
Bootstrap command refactoring: consolidate output modes (step 3)
This PR is a continuation to https://github.com/rust-lang/rust/pull/126731. It consolidates the output modes of bootstrap (`Print` vs `CaptureAll` vs `CaptureStdout`) and simplifies the logic around error printing (now a command error is always printed if the failure is not ignored). It also ports even more usages of `Command` to `BootstrapCommand`, most notably the git helpers and many usages of the `output` function.
The last commit was added because the third commit made two variants of the `Tool` enum unused (no idea why, but it seems to have been a false positive that they were used before).
It can be reviewed now, but I would wait with merging until at least a few days after https://github.com/rust-lang/rust/pull/126731, just to catch any potential issues from that PR before we move further.
As a next step, I want to clean up the API of the command a little bit to make usage easier (currently it's a bit verbose), and then continue with the rest of the tasks from the tracking issue.
As always, best reviewed commit by commit.
Tracking issue: https://github.com/rust-lang/rust/issues/126819
r? `@onur-ozkan`
try-job: aarch64-apple
TB: Refine protector end semantics
Tree Borrows has protector end tag semantics, namely that protectors ending cause a [special implicit read](https://perso.crans.org/vanille/treebor/diff.0.html) on all locations protected by that protector that have actually been accessed. See also #3067.
While this is enough for ensuring protectors allow adding/reordering reads, it does not prove that one can reorder writes. For this, we need to make this stronger, by making this implicit read be a write in cases when there was a write to the location protected by that protector, i.e. if the permission is `Active`.
There is a test that shows why this behavior is necessary, see `tests/fail/tree_borrows/protector-write-lazy.rs`.
Rollup of 5 pull requests
Successful merges:
- #126792 (wasm64 build with target-feature=+simd128,+atomics)
- #127195 (Remove unqualified form import of io::Error in process_vxworks.rs and fallback on remove_dir_impl for vxworks)
- #127287 (jsondocck: Use correct index for error message.)
- #127289 (rustdoc-json: Better representation of lifetime bounds in where clauses.)
- #127303 (chore: remove repeat words)
r? `@ghost`
`@rustbot` modify labels: rollup
When dry run is enabled, the command for finding LLDB version would succeed, but return an empty string. This was inadvertently enabling a code path that should only be executed when the LLDB is actually present and its version is valid. This commit makes sure that if the version is empty, LLDB will be considered not found.
jsondocck: Use correct index for error message.
If you misused a count command like ``@count` $some.selector '"T'"`, you would panic with OOB:
```
thread 'main' panicked at src/tools/jsondocck/src/main.rs:76:92:
index out of bounds: the len is 2 but the index is 2
```
This is because 57c85bd97d removed the file param, but didn't update the error case. We now error with:
```
Invalid command: Second argument to `@count` must be a valid usize (got `"T"`) on line 20
```
As some point I want to rewrite this code to avoid indexing in general, but this is a nice small fix.
r? `@GuillaumeGomez`
Remove unqualified form import of io::Error in process_vxworks.rs and fallback on remove_dir_impl for vxworks
Hi all,
This is to address issue #127084. On inspections it was found that io::Error refrences were all of qualified form and there was no need to add a unqualified form import. Also to successfully build rust for vxworks, we need to fallback on the remove_impl_dir implementations.
Thank you.
Optimize SipHash by reordering compress instructions
This PR optimizes hashing by changing the order of instructions in the sip.rs `compress` macro so the CPU can parallelize it better. The new order is taken directly from Fig 2.1 in [the SipHash paper](https://eprint.iacr.org/2012/351.pdf) (but with the xors moved which makes it a little faster). I attempted to optimize it some more after this, but I think this might be the optimal instruction order. Note that this shouldn't change the behavior of hashing at all, only statements that don't depend on each other were reordered.
It appears like the current order hasn't changed since its [original implementation from 2012](fada46c421 (diff-b751133c229259d7099bbbc7835324e5504b91ab1aded9464f0c48cd22e5e420R35)) which doesn't look like it was written with data dependencies in mind.
Running `./x bench library/core --stage 0 --test-args hash` before and after this change shows the following results:
Before:
```
benchmarks:
hash::sip::bench_bytes_4 7.20/iter +/- 0.70
hash::sip::bench_bytes_7 9.01/iter +/- 0.35
hash::sip::bench_bytes_8 8.12/iter +/- 0.10
hash::sip::bench_bytes_a_16 10.07/iter +/- 0.44
hash::sip::bench_bytes_b_32 13.46/iter +/- 0.71
hash::sip::bench_bytes_c_128 37.75/iter +/- 0.48
hash::sip::bench_long_str 121.18/iter +/- 3.01
hash::sip::bench_str_of_8_bytes 11.20/iter +/- 0.25
hash::sip::bench_str_over_8_bytes 11.20/iter +/- 0.26
hash::sip::bench_str_under_8_bytes 9.89/iter +/- 0.59
hash::sip::bench_u32 9.57/iter +/- 0.44
hash::sip::bench_u32_keyed 6.97/iter +/- 0.10
hash::sip::bench_u64 8.63/iter +/- 0.07
```
After:
```
benchmarks:
hash::sip::bench_bytes_4 6.64/iter +/- 0.14
hash::sip::bench_bytes_7 8.19/iter +/- 0.07
hash::sip::bench_bytes_8 8.59/iter +/- 0.68
hash::sip::bench_bytes_a_16 9.73/iter +/- 0.49
hash::sip::bench_bytes_b_32 12.70/iter +/- 0.06
hash::sip::bench_bytes_c_128 32.38/iter +/- 0.20
hash::sip::bench_long_str 102.99/iter +/- 0.82
hash::sip::bench_str_of_8_bytes 10.71/iter +/- 0.21
hash::sip::bench_str_over_8_bytes 11.73/iter +/- 0.17
hash::sip::bench_str_under_8_bytes 10.33/iter +/- 0.41
hash::sip::bench_u32 10.41/iter +/- 0.29
hash::sip::bench_u32_keyed 9.50/iter +/- 0.30
hash::sip::bench_u64 8.44/iter +/- 1.09
```
I ran this on my computer so there's some noise, but you can tell at least `bench_long_str` is significantly faster (~18%).
Also, I noticed the same compress function from the library is used in the compiler as well, so I took the liberty of copy-pasting this change to there as well.
Thanks `@semisol` for porting SipHash for another project which led me to notice this issue in Rust, and for helping investigate. <3
rustdoc: update to pulldown-cmark 0.11
r? rustdoc
This pull request updates rustdoc to the latest version of pulldown-cmark. Along with adding new markdown extensions (which this PR doesn't enable), the new pulldown-cmark version also fixes a large number of bugs. Because all text files successfully parse as markdown, these bugfixes change the output, which can break people's existing docs.
A crater run, https://github.com/rust-lang/rust/pull/121659, has already been run for this change.
The first commit upgrades and fixes rustdoc. The second commit adds a lint for the footnote and block quote parser changes, which break the largest numbers of docs in the Crater run. The strikethrough change was mitigated in pulldown-cmark itself.
Unblocks https://github.com/rust-lang/rust-clippy/pull/12876
