Change Backtrace::enabled atomic from SeqCst to Relaxed
This atomic is not synchronizing anything outside of its own value, so we don't need the `Acquire`/`Release` guarantee that all memory operations prior to the store are visible after the subsequent load, nor the `SeqCst` guarantee of all threads seeing all of the sequentially consistent operations in the same order.
Using `Relaxed` reduces the overhead of `Backtrace::capture()` in the case that backtraces are not enabled.
## Benchmark
```rust
#![feature(backtrace)]
use std::backtrace::Backtrace;
use std::sync::atomic::{AtomicUsize, Ordering};
use std::thread;
use std::time::Instant;
fn main() {
let begin = Instant::now();
let mut threads = Vec::new();
for _ in 0..64 {
threads.push(thread::spawn(|| {
for _ in 0..10_000_000 {
let _ = Backtrace::capture();
static LOL: AtomicUsize = AtomicUsize::new(0);
LOL.store(1, Ordering::Release);
}
}));
}
for thread in threads {
let _ = thread.join();
}
println!("{:?}", begin.elapsed());
}
```
**Before:** 6.73 seconds
**After:** 5.18 seconds
Add some JSDoc comments to rustdoc JS
This follows the Closure Compiler dialect of JSDoc, so we can use it to do some basic type checking. We don't plan to compile with Closure Compiler, just use it to check types. See https://github.com/google/closure-compiler/wiki/ for details.
To try checking the annotations, run:
```
npm i -g google-closure-compiler
google-closure-compiler -W VERBOSE build/x86_64-unknown-linux-gnu/doc/{search-index1.59.0.js,crates1.59.0.js} src/librustdoc/html/static/js/{search.js,main.js,storage.js} --externs src/librustdoc/html/static/js/externs.js >/dev/null
```
You'll see some warnings that "String continuations are not recommended". I'm not addressing those right now.
[Discussed on Zulip](https://rust-lang.zulipchat.com/#narrow/stream/266220-rustdoc/topic/doc.20format.20for.20JS/near/265209466).
r? `@GuillaumeGomez`
Fix duplicate derive clone suggestion
closes https://github.com/rust-lang/rust/issues/91492
The addition of:
```rust
derives.sort();
derives.dedup();
```
is what actually solves the problem.
The rest is just cleanup.
I want to improve the diagnostic message to provide the suggestion as a proper diff but ran into some problems, so I'll attempt that again in a follow up PR.
Allow reverse iteration of lowercase'd/uppercase'd chars
The PR implements `DoubleEndedIterator` trait for `ToLowercase` and `ToUppercase`.
This enables reverse iteration of lowercase/uppercase variants of character sequences.
One of use cases: determining whether a char sequence is a suffix of another one.
Example:
```rust
fn endswith_ignore_case(s1: &str, s2: &str) -> bool {
for eob in s1
.chars()
.flat_map(|c| c.to_lowercase())
.rev()
.zip_longest(s2.chars().flat_map(|c| c.to_lowercase()).rev())
{
match eob {
EitherOrBoth::Both(c1, c2) => {
if c1 != c2 {
return false;
}
}
EitherOrBoth::Left(_) => return true,
EitherOrBoth::Right(_) => return false,
}
}
true
}
```
This follows the Closure Compiler dialect of JSDoc, so we
can use it to do some basic type checking. We don't plan to
compile with Closure Compiler, just use it to check types. See
https://github.com/google/closure-compiler/wiki/ for details.
Fix failing tests
Fixes tests that have been failing in CI.
I hope it's ok but I've temporarily commented out some of the Windows resolver tests. I actually have a bigger fix for that test code as part of another PR. I could separate it out and patch as necessary but I'd prefer not to rush into that if possible.
r? `@Mark-Simulacrum`
Sync rustc_codegen_cranelift
The main highlight this sync is improved support for inline assembly. Thanks `@nbdd0121!` Inline assembly is still disabled by default for builds in the main rust repo though. Cranelift will now also be built from the crates.io releases rather than the git repo. Git repos are incompatible with vendoring.
r? `@ghost`
`@rustbot` label +A-codegen +A-cranelift +T-compiler
Move duplicates removal when generating results instead of when displaying them
Currently, we store 200 results per tab and then display them. However, it was possible to have duplicates which is why we have this check. However, instead of doing it when displaying the results, it's much better instead to do it even before to simplify the display part a bit.
r? `@jsha`
Improve suggestions for importing out-of-scope traits reexported as `_`
1. Fix up the `parent_map` query to prefer visible parents that _don't_ export items with the name `_`.
* I'm not sure if I modified this query properly. Not sure if we want to check for other idents than `kw::Underscore`.
* This also has the side-effect of not doing BFS on any modules re-exported as `_`, but I think that's desirable here too (or else we get suggestions for paths like `a::_::b` like in [this doctest example](https://play.rust-lang.org/?version=stable&mode=debug&edition=2021&gist=d9505ea45bb80adf40bb991298f952be)).
2. Bail in `try_print_visible_def_path` if the `def_id` is re-exported as `_`, which will fall back to printing the def-id's real (definition) path.
* Side-effect of this is that we print paths that are not actually public, but it seems we already sometimes suggest `use`ing paths that are private anyways. See [this doctest example](https://play.rust-lang.org/?version=stable&mode=debug&edition=2021&gist=bad513ed3241f8ff87579eed8046ad10) for demonstration of current behavior.
3. Suggest a glob-import (for example `my_library::prelude::*`) if the trait in question is only pub-exported as `_`, as a fallback.
```
use foo::bar::prelude::*; // trait MyTrait
```
* I think this is good fallback behavior to suggest instead of doing nothing. Thanks to the original issue filer for suggesting this.
I was somewhat opinionated about behaviors in this PR, and I'm totally open to limiting the impact of my changes or only landing parts of this. Happy to receive feedback if there are better ways to the same end.
Fixes#86035
Implement StableHash for BitSet and BitMatrix via Hash
This fixes an issue where bit sets / bit matrices the same word
content but a different domain size would receive the same hash.
Remove 'speculative evaluation' of predicates
Performing 'speculative evaluation' introduces caching bugs that
cannot be fixed without invasive changes to projection.
Hopefully, we can win back most of the performance lost by
re-adding 'cache completion'
Fixes#90662
rustdoc: make `--passes` and `--no-defaults` have no effect
Fixes#91714
One potential issue is that currently there is no stable way to achieve `--document-hidden-items`. This affects test `issue-15347`.
I also had to modify the tests `issue-42875` and `no-compiler-export`. Regardless of combinations of `--document-hidden-items` and `--document-private-items`, I was unable to get these to pass without the modifications. I left behind a comment noting the change.
Eliminate `ObligationCauseData`
This makes `Obligation` two words bigger, but avoids allocating a lot of the time.
I previously tried this in #73983 and it didn't help much, but local timings look more promising now.
r? `@ghost`
I think that s == "" is the only edge case (as it makes iter.next() return None the first time). The early return is necessary so that the last character of 'out' isn't popped if s == "" && !frag.need_backline
This makes `Obligation` two words bigger, but avoids allocating a lot of
the time.
I previously tried this in #73983 and it didn't help much, but local
timings look more promising now.
Rollup of 4 pull requests
Successful merges:
- #91791 (Fix an ICE when lowering a float with missing exponent magnitude)
- #91878 (Remove `in_band_lifetimes` from `rustc_infer`)
- #91895 (Remove `in_band_lifetimes` for `rustc_monomorphize`)
- #92029 (Explicitly set no ELF flags for .rustc section)
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
Explicitly set no ELF flags for .rustc section
For a data section, the object crate will set the SHF_ALLOC by default, which is exactly what we don't want. Explicitly set sh_flags to zero to avoid this.
I checked with `objdump -h` that this produces the right flags for ELF.
Fixes#92013.
Matthias Krüger