In particular, this leads to lots of "multiple applicable items in scope" errors because you have to disambiguate `MyTrait::as_raw_fd` from `AsRawFd::as_raw_fd` at each call site. In generic contexts, when passing the type to a function that takes `impl AsRawFd` it's also sometimes required to use `T: MyTrait + AsRawFd`, which wouldn't be necessary if I could write `MyTrait: AsRawFd`.
After this PR, the code can be simpler:
```rust
trait MyTrait: AsRawFd {}
Auto merge of #98755 - nnethercote:faster-vec-insert, r=cuviper
Optimize `Vec::insert` for the case where `index == len`.
By skipping the call to `copy` with a zero length. This makes it closer
to `push`.
I did this recently for `SmallVec`
(https://github.com/servo/rust-smallvec/pull/282) and it was a big perf win in
one case. Although I don't have a specific use case in mind, it seems
worth doing it for `Vec` as well.
Things to note:
- In the `index < len` case, the number of conditions checked is
unchanged.
- In the `index == len` case, the number of conditions checked increases
by one, but the more expensive zero-length copy is avoided.
- In the `index > len` case the code now reserves space for the extra
element before panicking. This seems like an unimportant change.
Auto merge of #98570 - SparrowLii:deadlock, r=cjgillot
get rid of `tcx` in deadlock handler when parallel compilation
This is a very obscure and hard-to-trace problem that affects thread scheduling. If we copy `tcx` to the deadlock handler thread, it will perform unpredictable behavior and cause very weird problems when executing `try_collect_active_jobs`(For example, the deadlock handler thread suddenly preempts the content of the blocked worker thread and executes the unknown judgment branch, like #94654).
Fortunately we can avoid this behavior by precomputing `query_map`. This change fixes the following ui tests failure on my environment when set `parallel-compiler = true`:
```
[ui] src/test\ui\async-await\no-const-async.rs
[ui] src/test\ui\infinite\infinite-struct.rs
[ui] src/test\ui\infinite\infinite-tag-type-recursion.rs
[ui] src/test\ui\issues\issue-3008-1.rs
[ui] src/test\ui\issues\issue-3008-2.rs
[ui] src/test\ui\issues\issue-32326.rs
[ui] src/test\ui\issues\issue-57271.rs
[ui] src/test\ui\issues\issue-72554.rs
[ui] src/test\ui\parser\fn-header-semantic-fail.rs
[ui] src/test\ui\union\union-nonrepresentable.rs
```
Auto merge of #98820 - RalfJung:rollup-i3mip9a, r=RalfJung
Rollup of 6 pull requests
Successful merges:
- #98701 (Add regression test for #50439)
- #98715 (add ice test for #97047)
- #98753 (Fix `x dist rust-dev` on a fresh checkout)
- #98805 (Add #95469 to the release notes)
- #98812 (feat: Add a documentation problem issue template)
- #98819 (update Miri)
Auto merge of #97585 - lqd:const-alloc-intern, r=RalfJung
CTFE interning: don't walk allocations that don't need it
The interning of const allocations visits the mplace looking for references to intern. Walking big aggregates like big static arrays can be costly, so we only do it if the allocation we're interning contains references or interior mutability.
Walking ZSTs was avoided before, and this optimization is now applied to cases where there are no references/relocations either.
---
While initially looking at this in the context of #93215, I've been testing with smaller allocations than the 16GB one in that issue, and with different init/uninit patterns (esp. via padding).
In that example, by default, `eval_to_allocation_raw` is the heaviest query followed by `incr_comp_serialize_result_cache`. So I'll show numbers when incremental compilation is disabled, to focus on the const allocations themselves at 95% of the compilation time, at bigger array sizes on these minimal examples like `static ARRAY: [u64; LEN] = [0; LEN];`.
That is a close construction to parts of the `ctfe-stress-test-5` benchmark, which has const allocations in the megabytes, while most crates usually have way smaller ones. This PR will have the most impact in these situations, as the walk during the interning starts to dominate the runtime.
Unicode crates (some of which are present in our benchmarks) like `ucd`, `encoding_rs`, etc come to mind as having bigger than usual allocations as well, because of big tables of code points (in the hundreds of KB, so still an order of magnitude or 2 less than the stress test).
In a check build, for a single static array shown above, from 100 to 10^9 u64s (for lengths in powers of ten), the constant factors are lowered:
(log scales for easier comparisons)
(linear scale for absolute diff at higher Ns)
For one of the alternatives of that issue
```rust
const ROWS: usize = 100_000;
const COLS: usize = 10_000;
static TWODARRAY: [[(u64, u8); COLS]; ROWS] = [[(0, 0); COLS]; ROWS];
```
then interning/walking does not dominate anymore (but means there is likely still some interesting work left to do here).
Compile times in this case rise up quite a bit, and avoiding interning walks has less impact: around 23%, from 730s on master to 568s with this PR.
UB maybe introduced when an FFI exception happens in a `C-unwind` foreign function and it propagates through a crate compiled with `-C panic=unwind` into a crate compiled with `-C panic=abort` (#96926).
To prevent this unsoundness from happening, we will disallow a crate compiled with `-C panic=unwind` to be linked into `panic-abort` *if* it contains a call to `C-unwind` foreign function or function pointer. If no such call exists, then we continue to allow such mixed panic mode linking because it's sound (and stable). In fact we still need the ability to do mixed panic mode linking for std, because we only compile std once with `-C panic=unwind` and link it regardless panic strategy.
For libraries that wish to remain compile-once-and-linkable-to-both-panic-runtimes, a `ffi_unwind_calls` lint is added (gated under `c_unwind` feature gate) to flag any FFI unwind calls that will cause the linkable panic runtime be restricted.
fn main() {
// Call to Rust function is fine regardless ABI.
foo::foo();
// Call to foreign function, will cause the crate to be unlinkable to panic-abort if compiled with `-Cpanic=unwind`.
unsafe { foo(); }
//~^ WARNING call to foreign function with FFI-unwind ABI
let ptr: extern "C-unwind" fn() = foo::foo;
// Call to function pointer, will cause the crate to be unlinkable to panic-abort if compiled with `-Cpanic=unwind`.
ptr();
//~^ WARNING call to function pointer with FFI-unwind ABI
}
```
Auto merge of #91743 - cjgillot:enable_mir_inlining_inline_all, r=oli-obk
Enable MIR inlining
Continuation of https://github.com/rust-lang/rust/pull/82280 by `@wesleywiser.`
#82280 has shown nice compile time wins could be obtained by enabling MIR inlining.
Most of the issues in https://github.com/rust-lang/rust/issues/81567 are now fixed,
except the interaction with polymorphization which is worked around specifically.
I believe we can proceed with enabling MIR inlining in the near future
(preferably just after beta branching, in case we discover new issues).
Steps before merging:
- [x] figure out the interaction with polymorphization;
- [x] figure out how miri should deal with extern types;
- [x] silence the extra arithmetic overflow warnings;
- [x] remove the codegen fulfilment ICE;
- [x] remove the type normalization ICEs while compiling nalgebra;
- [ ] tweak the inlining threshold.
Auto merge of #98802 - Dylan-DPC:rollup-u6mwx27, r=Dylan-DPC
Rollup of 5 pull requests
Successful merges:
- #98639 (Factor out `hir::Node::Binding`)
- #98653 (Add regression test for #79494)
- #98763 (bootstrap: illumos platform flags for split-debuginfo)
- #98766 (cleanup mir visitor for `rustc::pass_by_value`)
- #98783 (interpret: make a comment less scary)
Rollup merge of #98766 - lcnr:mir-visit-pass_by_value, r=oli-obk
cleanup mir visitor for `rustc::pass_by_value`
by changing `& $($mutability)?` to `$(& $mutability)?`
I also did some formatting changes because I started doing them for the visit methods I changed and then couldn't get myself to stop xx, I hope that's still fairly easy to review.
Rollup merge of #98497 - compiler-errors:span-inference-note, r=lcnr
Improve some inference diagnostics
- Properly point out point location where "type must be known at this point", or else omit the note if it's not associated with a useful span.
- Fix up some type ambiguity diagnostics, errors shouldn't say "cannot infer type for reference `&'a ()`" when the given type has no inference variables.
Rollup merge of #98418 - topjohnwu:macos-dylib, r=jyn514
Allow macOS to build LLVM as shared library
Inspired by how [homebrew](https://github.com/Homebrew/homebrew-core/blob/HEAD/Formula/llvm.rb) builds and distributes llvm, here we manually create a symlink with a versioned dylib path to make `llvm-config` work properly. Note, the resulting `rustc` executable and `librustc_driver-<hash>.dylib` still links to the un-versioned `libLLVM.dylib` as expected when distributed in the final output. I have confirmed this by checking `otool -L` on both binaries.
After the change, enabling `llvm.link-shared` and `llvm.thin-lto` will be possible on macOS.
Auto merge of #93967 - cjgillot:short-struct-span, r=petrochenkov
Shorten def_span for more items.
The `def_span` query only returns the signature span for functions.
Struct/enum/union definitions can also have a very long body.
This PR shortens the associated span.
Auto merge of #98767 - Dylan-DPC:rollup-j1gq5sr, r=Dylan-DPC
Rollup of 6 pull requests
Successful merges:
- #97488 (Suggest blanket impl to the local traits)
- #98585 (Make `ThinBox<T>` covariant in `T`)
- #98644 (fix ICE with -Wrust-2021-incompatible-closure-captures)
- #98739 (fix grammar in useless doc comment lint)
- #98741 (Many small deriving cleanups)
- #98756 (Use const instead of function and make it private)
Rollup merge of #98585 - cuviper:covariant-thinbox, r=thomcc
Make `ThinBox<T>` covariant in `T`
Just like `Box<T>`, we want `ThinBox<T>` to be covariant in `T`, but the
projection in `WithHeader<<T as Pointee>::Metadata>` was making it
invariant. This is now hidden as `WithOpaqueHeader`, which we type-cast
whenever the real `WithHeader<H>` type is needed.
Fixes the problem noted in <https://github.com/rust-lang/rust/issues/92791#issuecomment-1104636249>.
Andy Fiddaman [Fri, 1 Jul 2022 13:21:18 +0000 (13:21 +0000)]
bootstrap: illumos platform flags for split-debuginfo
Bootstrap currently provides `-Zunstable-options` for platforms
when using split debuginfo - this commit adds it for the illumos
target too.
Auto merge of #98730 - matthiaskrgr:rollup-2c4d4x5, r=matthiaskrgr
Rollup of 10 pull requests
Successful merges:
- #97629 ([core] add `Exclusive` to sync)
- #98503 (fix data race in thread::scope)
- #98670 (llvm-wrapper: adapt for LLVMConstExtractValue removal)
- #98671 (Fix source sidebar bugs)
- #98677 (For diagnostic information of Boolean, remind it as use the type: 'bool')
- #98684 (add test for 72793)
- #98688 (interpret: add From<&MplaceTy> for PlaceTy)
- #98695 (use "or pattern")
- #98709 (Remove unneeded methods declaration for old web browsers)
- #98717 (get rid of tidy 'unnecessarily ignored' warnings)
Auto merge of #98752 - matthiaskrgr:rollup-uwimznc, r=matthiaskrgr
Rollup of 9 pull requests
Successful merges:
- #98610 (fix `emit_inference_failure_err` ICE)
- #98640 (Let rust-analyzer ship on stable, non-preview)
- #98686 (add ice test for 46511)
- #98727 (rustdoc: filter '_ lifetimes from ty::PolyTraitRef)
- #98729 (clarify that ExactSizeIterator::len returns the remaining length)
- #98733 (Request to be notified of MIR changes)
- #98734 (Update RELEASES.md)
- #98745 (Add a `--build-dir` flag to rustbuild)
- #98749 (Add macro_rules! rustdoc change to 1.62 relnotes)
The existing derive code allows for various possibilities that aren't
needed in practice, which complicates the code. There are only a few
auto-derived traits and new ones are unlikely, so this commit simplifies
things.
- `PtrTy` has been eliminated. The `Raw` variant was never used, and the
lifetime for the `Borrowed` variant was always `None`. That left just
the mutability field, which has been inlined as necessary.
- `MethodDef::explicit_self` was a confusing `Option<Option<PtrTy>>`.
Indicating either `&self` or nothing. It's now a `bool`.
- `borrowed_self` is renamed as `self_ref`.
- `Ty::Ptr` is renamed to `Ty::Ref`.
#96630 was tagged <kbd>relnotes</kbd> but didn't make it into the notes. Given this is a compatibility issue (https://github.com/rust-lang/rust/issues/97030, https://github.com/rust-lang/rust/issues/98735, https://github.com/rust-lang/rust/issues/98743), it probably *should* be retroactively added.
Rollup merge of #98745 - thomcc:build-dir-arg, r=jyn514
Add a `--build-dir` flag to rustbuild
This adds an optional `--build-dir <path>` flag to rustbuild (to both the python and rust code in src/bootstrap). If provided, it overrides build directory from the config file (if any was provided).
My reason for wanting this is that I often will make a change, save, and then go run `x.py check` or `x.py test` (or something). Because I've saved, vscode will start doing its thing in the background, but this will take the file lock, preventing `x.py` from running until vscode finishes whatever it's doing (since the manually invoked x.py won't be able to acquire said file lock). This is annoying, because I'd rather the command I explicitly invoke *not* wait for r-a to complete, as r-a's check is conceptually a background task (and one which can take quite some time to complete).
Anyway, while there are likely other ways this could be handled, if you have the disk space an easy way is to just have vscode be configured to use a different build directory, and then they never have to block each-other.
This can currently be arranged without this patch, by maintaining two `config.toml`s, one of which has a different build dir, and just exists to be passed into the overridden check command in vscode.
Unfortunately, this has the downside of requiring I maintain two `config.toml`s and keep them (at least somewhat) in sync, aside from the build dir. I dislike for several reasons, not the least of which because I know myself well enough to know that these will inevitably get out of sync and confuse me in the future (perhaps this case would be different since I've thought about it enough to write this patch? Who knows, I'd rather not find out).
Either way, it would be much easier for me to have a way for *only* the build directory to differ, which this patch provides by way of a new flag. I suggested this to `@jyn514` who indicated it sounded reasonable so long as it didn't add too much complexity, which I think I've achieved, but he can be the judge.
Anyway, with this patch I can just use something like `["python3", "x.py", "check", "--build-dir", "build-vscode", "--json-output"]` as the overridden check command to rust-analyzer, and do not need to futz with any additional `config.toml`s. Which is very nice!
I've tested this manually, and can confirm that it works. I'm not sure if it needs automated tests, or where I should add them if so.
r? `@jyn514` (who has had to put up with my complaints about this... many times. <3)
Rollup merge of #98640 - cuviper:stable-rust-analyzer, r=Mark-Simulacrum
Let rust-analyzer ship on stable, non-preview
The consensus on rust-lang/rust-analyzer#12432 seems to be that we are ready for `rust-analyzer` to ship as a rustup component on the beta and stable channels. This won't always be the preferred distribution method, e.g. the VS Code extension will probably still independently update to its weekly releases, but it's still useful to have a component that follows the release train with the rest of the Rust toolchain. So this removes the nightly-only gating on the bundled component, and removes the "-preview" suffix as well by the usual renaming mechanism.
Optimize `Vec::insert` for the case where `index == len`.
By skipping the call to `copy` with a zero length. This makes it closer
to `push`.
I did this recently for `SmallVec`
(https://github.com/servo/rust-smallvec/pull/282) and it was a big perf win in
one case. Although I don't have a specific use case in mind, it seems
worth doing it for `Vec` as well.
Things to note:
- In the `index < len` case, the number of conditions checked is
unchanged.
- In the `index == len` case, the number of conditions checked increases
by one, but the more expensive zero-length copy is avoided.
- In the `index > len` case the code now reserves space for the extra
element before panicking. This seems like an unimportant change.
Wesley Wiser [Fri, 1 Oct 2021 01:58:49 +0000 (21:58 -0400)]
Don't assert polymorphization has taken effect in const eval
Const eval no longer runs MIR optimizations so unless this is getting
run as part of a MIR optimization like const-prop, there can be unused
type parameters even if polymorphization is enabled.
Matthias Krüger [Thu, 30 Jun 2022 17:55:57 +0000 (19:55 +0200)]
Rollup merge of #98717 - RalfJung:make-tidy-less-annoying, r=jyn514
get rid of tidy 'unnecessarily ignored' warnings
I think these warnings are quite pointless: when I say `allow(foo)` in my code, that doesn't necessarily mean that I expect `foo` to happen -- it just means that I am okay with `foo` happening.
For example, having to add and remove `ignore-tidy-linelength` as the longest line in the file keeps growing and shrinking is just annoying and doesn't benefit anyone, IMO. This usually incurs *two* CI roundtrips: first CI tells you that line lengths in your test file are ignored unnecessarily, so you go and remove that attribute; then CI tells you that now your line numbers changed, so you re-bless your tests (often takes >5min if parts of rustc need rebuilding because `./x.py fmt` changed something somewhere). That's just a lot of wasted effort and time and patience.
projects / rust.git / log