Remove braces when fixing a nested use tree into a single item
[Back in 2019](https://github.com/rust-lang/rust/pull/56645) I added rustfix support for the `unused_imports` lint, to automatically remove them when running `cargo fix`. For the most part this worked great, but when removing all but one childs of a nested use tree it turned `use foo::{Unused, Used}` into `use foo::{Used}`. This is slightly annoying, because it then requires you to run `rustfmt` to get `use foo::Used`.
This PR automatically removes braces and the surrouding whitespace when all but one child of a nested use tree are unused. To get it done I had to add the span of the nested use tree to the AST, and refactor a bit the code I wrote back then.
A thing I noticed is, there doesn't seem to be any `//@ run-rustfix` test for fixing the `unused_imports` lint. I created a test in `tests/suggestions` (is that the right directory?) that for now tests just what I added in the PR. I can followup in a separate PR to add more tests for fixing `unused_lints`.
This PR is best reviewed commit-by-commit.
Rollup of 3 pull requests
Successful merges:
- #124548 (Handle normalization failure in `struct_tail_erasing_lifetimes`)
- #124761 (Fix insufficient logic when searching for the underlying allocation)
- #124864 (rustdoc: use stability, instead of features, to decide what to show)
r? `@ghost`
`@rustbot` modify labels: rollup
rustdoc: use stability, instead of features, to decide what to show
Fixes#124635
To decide if internal items should be inlined in a doc page, check if the crate is itself internal, rather than if it has the rustc_private feature flag. The standard library uses internal items, but is not itself internal and should not show internal items on its docs pages.
Fix insufficient logic when searching for the underlying allocation
This PR fixes the logic inside the `invalid_reference_casting` lint, when trying to lint on bigger memory layout casts.
More specifically when looking for the "underlying allocation" we were wrongly assuming that when we got `&mut slice[index]` that `slice[index]` was the allocation, but it's not.
Fixes https://github.com/rust-lang/rust/issues/124685
Handle normalization failure in `struct_tail_erasing_lifetimes`
Fixes#113272
The ICE occurred because the struct being normalized had an error. This PR adds some defensive code to guard against that.
rustc: Some small changes for the wasm32-wasip2 target
This commit has a few changes for the wasm32-wasip2 target. The first two are aimed at improving the compatibility of using `clang` as an external linker driver on this target. The default target to LLVM is updated to match the Rust target and additionally the `-fuse-ld=lld` argument is dropped since that otherwise interferes with clang's own linker detection. The only linker on wasm targets is LLD but on the wasip2 target a wrapper around LLD, `wasm-component-ld`, is used to drive the process and perform steps necessary for componentization.
The final commit changes the output of all objects on the wasip2 target to being PIC by default. This improves compatibilty with shared libaries but notably does not mean that there's a turnkey solution for shared libraries. The hope is that by having the standard libray work both with and without dynamic libraries will make experimentation easier.
Rollup of 4 pull requests
Successful merges:
- #124470 (std::net: Socket::new_raw now set to SO_NOSIGPIPE on freebsd.)
- #124782 (add note about `AlreadyExists` to `create_new`)
- #124788 (Convert instances of `target_os = "macos"` to `target_vendor = "apple"`)
- #124838 (next_power_of_two: add a doctest to show what happens on 0)
r? `@ghost`
`@rustbot` modify labels: rollup
Convert instances of `target_os = "macos"` to `target_vendor = "apple"`
https://github.com/rust-lang/rust/pull/124491 migrated towards using `target_vendor = "apple"` more, as there's very little difference between iOS, tvOS, watchOS and visionOS. In that PR, I only did the changes where the standard library already had fixes for iOS, that I could confidently apply to the other targets.
However, there's actually also not that big of a gap between macOS and the aforementioned platforms - so in this PR, I've gone through a few of the instances of `target_os = "macos"` and replaced it with `target_vendor = "apple"` to improve support on those platforms, see the commits for details.
r? workingjubilee
CC `@thomcc` `@simlay` (do tell me if I should stop pinging you on these Apple PRs)
`@rustbot` label O-apple
Fuchsia test runner: fixup script
This commit fixes several issues in the fuchsia-test-runner.py script:
1. Migrate from `pm` to `ffx` for package management, as `pm` is now deprecated. Furthermore, the `pm` calls used in this script no longer work at Fuchsia's HEAD. This is the largest change in this commit, and impacts all steps around repository management (creation and registration of the repo, as well as package publishing).
2. Allow for `libtest` to be either statically or dynamically linked. The script assumed it was dynamically linked, but the current Rust behavior at HEAD is to statically link it.
3. Minor cleanup to use `ffx --machine json` rather than string parsing.
4. Minor cleanup to the docs around the script.
Improve `rustc_parse::Parser`'s debuggability
The main event is the final commit where I add `Parser::debug_lookahead`. Everything else was basically cleaning up things that bugged me (debugging, as it were) until I felt comfortable enough to actually work on it.
The motivation is that it's annoying as hell to try to figure out how the debug infra works in rustc without having basic queries like `debug!(?parser);` come up "empty". However, Parser has a lot of fields that are mostly irrelevant for most debugging, like the entire ParseSess. I think `Parser::debug_lookahead` with a capped lookahead might be fine as a general-purpose Debug impl, but this adapter version was suggested to allow more choice, and admittedly, it's a refined version of what I was already handrolling just to get some insight going.
To decide if internal items should be inlined in a doc page,
check if the crate is itself internal, rather than if it has
the rustc_private feature flag. The standard library uses
internal items, but is not itself internal and should not show
internal items on its docs pages.
I tried debugging a parser-related issue but found it annoying to not be
able to easily peek into the Parser's token stream.
Add a convenience fn that offers an opinionated view into the parser,
but one that is useful for answering basic questions about parser state.
coverage: Branch coverage support for let-else and if-let
This PR adds branch coverage instrumentation for let-else and if-let, including let-chains.
This lifts two of the limitations listed at #124118.
This commit changes the new `wasm32-wasip2` target to being PIC by
default rather than the previous non-PIC by default. This change is
intended to make it easier for the standard library to be used in a
shared object in its precompiled form. This comes with a hypothetical
modest slowdown but it's expected that this is quite minor in most use
cases or otherwise wasm compilers and/or optimizing runtimes can elide
the cost.
Do not ICE on `AnonConst`s in `diagnostic_hir_wf_check`
Fixes#122989
Below is the snippet from #122989 that ICEs:
```rust
trait Traitor<const N: N<2> = 1, const N: N<2> = N> {
fn N(&N) -> N<2> {
M
}
}
trait N<const N: Traitor<2> = 12> {}
```
The `AnonConst` that triggers the ICE is the `2` in the param `const N: N<2> = 1`. The currently existing code in `diagnostic_hir_wf_check` deals only with `AnonConst`s that are default values of some param, but the `2` is not a default value. It is just an `AnonConst` HIR node inside a `TraitRef` HIR node corresponding to `N<2>`. Therefore the existing code cannot handle it and this PR ensures that it does.
Rollup of 5 pull requests
Successful merges:
- #124738 (rustdoc: dedup search form HTML)
- #124827 (generalize hr alias: avoid unconstrainable infer vars)
- #124832 (narrow down visibilities in `rustc_parse::lexer`)
- #124842 (replace another Option<Span> by DUMMY_SP)
- #124846 (Don't ICE when we cannot eval a const to a valtree in the new solver)
r? `@ghost`
`@rustbot` modify labels: rollup
This commit fixes several issues in the fuchsia-test-runner.py script:
1. Migrate from `pm` to `ffx` for package management, as `pm` is now
deprecated. Furthermore, the `pm` calls used in this script no longer
work at Fuchsia's HEAD. This is the largest change in this commit, and
impacts all steps around repository management (creation and
registration of the repo, as well as package publishing).
2. Allow for `libtest` to be either statically or dynamically linked.
The script assumed it was dynamically linked, but the current Rust
behavior at HEAD is to statically link it.
3. Minor cleanup to use `ffx --machine json` rather than string parsing.
4. Minor cleanup to the docs around the script.
Don't ICE when we cannot eval a const to a valtree in the new solver
Use `const_eval_resolve` instead of `try_const_eval_resolve` because naming aside, the former doesn't ICE when a value can't be evaluated to a valtree.
r? lcnr
rustdoc: dedup search form HTML
This change constructs the search form HTML using JavaScript, instead of plain HTML. It uses a custom element because
- the [parser]'s insert algorithm runs the connected callback synchronously, so we won't get layout jank
- it requires very little HTML, so it's a real win in size
[parser]: https://html.spec.whatwg.org/multipage/parsing.html#create-an-element-for-the-token
This shrinks the standard library by about 60MiB, by my test.
There should be no visible changes. Just use less disk space.
never patterns: lower never patterns to `Unreachable` in MIR
This lowers a `!` pattern to "goto Unreachable". Ideally I'd like to read from the place to make it clear that the UB is coming from an invalid value, but that's tricky so I'm leaving it for later.
r? `@compiler-errors` how do you feel about a lil bit of MIR lowering
Correct the const stabilization of `last_chunk` for slices
`<[T]>::last_chunk` should have become const stable as part of <https://github.com/rust-lang/rust/pull/117561>. Update the const stability gate to reflect this.
f16::is_sign_{positive,negative} were feature-gated on f128
`f16::is_sign_positive` and `f16::is_sign_negative` were feature-gated on `"f128"` instead of `"f16"`.
Implement lldb formatter for "clang encoded" enums (LLDB 18.1+) (V3)
This is a redo of PR (#124458) which was approved previously but force-pushed out. Then a V2 (#124745) failed `debuginfo\msvc-pretty-enums.rs` test during merge.
I've fixed the test and checked it to pass on Windows with `.\x.ps1 test .\tests\debuginfo\msvc-pretty-enums.rs`
Below is the original summary:
## Summary:
fixes#79530
I landed a fix last year to enable `DW_TAG_variant_part` encoding in LLDBs (https://reviews.llvm.org/D149213). This PR is a corresponding fix in synthetic formatters to decode that information.
This is in no way perfect implementation but at least it improves the status quo. But most types of enums will be visible and debuggable in some way.
I've also updated most of the existing tests that touch enums and re-enabled test cases based on LLDB for enums.
## Test Plan:
ran tests `./x test tests/debuginfo/`. Also tested manually in LLDB CLI and LLDB VSCode
## Other Thoughs:
A better approach would probably be adopting [formatters from codelldb](https://github.com/vadimcn/codelldb/blob/master/formatters/rust.py). There is some neat hack that hooks up summary provider via synthetic provider which can ultimately fix more display issues for Rust types and enums too. But getting it to work well might take more time that I have right now.
Update cc crate for bootstrap to v1.0.97
Reason:
In order to build the Windows version of the Rust toolchain for the Android platform, the following patch to the cc is crate is required to avoid incorrectly determining that we are building with the Android NDK: 57853c4bf8
This patch is present in version 1.0.80 and newer versions of the cc crate. The rustc source distribution currently has 3 different versions of cc in the vendor directory, only one of which has the necessary fix.
We (the Android Rust toolchain) are currently maintaining local patches to upgrade the cc crate dependency versions, which we would like to upstream.
Furthermore, beyond the specific reason, the cc crate in bootstrap is currently pinned at an old version due to problems in the past when trying to update it. It is worthwhile to figure out and resolve these problems so we can keep the dependency up-to-date.
Other fixes:
As of cc v1.0.78, object files are prefixed with a 16-character hash.
Update src/bootstrap/src/core/build_steps/llvm.rs to account for this to
avoid failures when building libunwind and libcrt. Note that while the hash
prefix was introduced in v1.0.78, in order to determine the names of the
object files without scanning the directory, we rely on the compile_intermediates
method, which was introduced in cc v1.0.86
As of cc v1.0.86, compilation on MacOS uses the -mmacosx-version-min flag.
A long-standing bug in the CMake rules for compiler-rt causes compilation
to fail when this flag is specified. So we add a workaround to suppress this
flag.
Updating to cc v1.0.91 and newer requires fixes to bootstrap unit tests.
The unit tests use targets named "A", "B", etc., which fail a validation
check introduced in 1.0.91 of the cc crate.
As of cc v1.0.74, the SDKROOT environment variable is used on Darwin if present,
regardless of whether it is for the correct platform or not. This is fixed in cc v1.0.97.
Adjust 64-bit ARM data layouts for LLVM update
LLVM has updated data layouts to specify `Fn32` on 64-bit ARM to avoid C++ accidentally underaligning functions when trying to comply with member function ABIs.
This should only affect Rust in cases where we had a similar bug (I don't believe we have one), but our data layout must match to generate code.
As a compatibility adaptatation, if LLVM is not version 19 yet, `Fn32` gets voided from the data layout.
See llvm/llvm-project#90415
`@rustbot` label: +llvm-main
cc `@krasimirgg`
r? `@durin42`
