Adapt codegen tests for NUW inference
These were broken by 462cb3cd6c
Let me know if you think we should have a FIXME / tracking issue to update the tests after the LLVM 20 upgrade to make these required.
`@rustbot` label: +llvm-main
r? `@nikic`
Normalize target-cpus.rs stdout test for LLVM changes
LLVM has recently added support for the `lime1` CPU in 35cce408ee, so the `target-cpus.rs` test currently produces different output depending on the LLVM version.
This CL adds a normalization directive, to remove the new CPU from the output list.
Alternatives fixes I can think of:
* Add two revisions of the test (one per LLVM version)
* Ignore the test on one of the LLVM versions
* I dislike this, because it's possible that the test won't get updated for the next LLVM version.
I don't think the exact list of target CPUs is relevant for this test, so it shouldn't be too bad if the normalization sticks around longer than necessary.
`@rustbot` label: +llvm-main
CI: rfl: move job forward to Linux v6.13-rc1
Linux v6.13-rc1 contains commit 28e848386b92 ("rust: block: fix formatting of `kernel::block::mq::request` module"), which in turn contains commit c95bbb59a9b2 ("rust: enable arbitrary_self_types and remove `Receiver`"), which is why we had a hash rather than a tag.
r? ```@Kobzol``` ```@lqd```
try-job: x86_64-rust-for-linux
```@rustbot``` label A-rust-for-linux
```@bors``` try
Replace black with ruff in `tidy`
`ruff` can both lint and format Python code (in fact, it should be a mostly drop-in replacement for `black` in terms of formatting), so it's not needed to use `black` anymore. This PR removes `black` and replaces it with `ruff`, to get rid of one Python dependency, and also to make Python formatting faster (although that's a small thing).
If we decide to merge this, we'll need to "reformat the world" - `ruff` is not perfectly compatible with `black`, and it also looks like `black` was actually ignoring some files before. I tried it locally (`./x test tidy --extra-checks=py:fmt --bless`) and it also reformatted some code in subtrees (e.g. `clippy` or `rustc_codegen_gcc`) - I'm not sure how to handle that.
implement checks for tail calls
Quoting the [RFC draft](https://github.com/phi-go/rfcs/blob/guaranteed-tco/text/0000-explicit-tail-calls.md):
> The argument to become is a function (or method) call, that exactly matches the function signature and calling convention of the callee. The intent is to ensure a matching ABI. Note that lifetimes may differ as long as they pass borrow checking, see [below](https://github.com/phi-go/rfcs/blob/guaranteed-tco/text/0000-explicit-tail-calls.md#return-type-coercion) for specifics on the return type.
> Tail calling closures and tail calling from closures is not allowed. This is due to the high implementation effort, see below, this restriction can be lifted by a future RFC.
> Invocations of operators were considered as valid targets but were rejected on grounds of being too error-prone. In any case, these can still be called as methods.
> Tail calling [variadic functions](https://doc.rust-lang.org/beta/unstable-book/language-features/c-variadic.html) and tail calling from variadic functions is not allowed. As support for variadic function is stabilized on a per target level, support for tail-calls regarding variadic functions would need to follow a similar approach. To avoid this complexity and to minimize implementation effort for backends, this interaction is currently not allowed but support can be added with a future RFC.
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The checks are implemented as a query, similarly to `check_unsafety`.
The code is cherry-picked straight out of #112657 which was written more than a year ago, so I expect we might need to change some things ^^"
Formatter::with_options takes self as a mutable reference (`&'a mut
Formatter<'b>`). `'a` and `'b` need to be different lifetimes. Just taking `&'a
mut Formatter<'a>` and trusting in Rust being able to implicitely convert from
`&'a mut Formatter<'b>` if necessary (after all, `'a` must be smaller than `'b`
anyway) fails because `'b` is behind a *mutable* reference. For background on
on this behavior, see https://doc.rust-lang.org/nomicon/subtyping.html#variance.
The idea behind this is to make implementing `fmt::FormattingOptions` (as well
as any future changes to `std::Formatter`) easier.
In theory, this might have a negative performance impact because of the
additional function calls. However, I strongly believe that those will be
inlined anyway, thereby producing assembly code that has comparable performance.
Fix missing newlines that rustfmt removed.
fix trailing whitespace
Fix duplicate word.
Reformat panic reasons into a list
remove trailing whitespace 2 electric boogaloo
Change verbe tense.
Integrate suggestions
This mainly aids in error recovery but also makes it a bit easier to handle lifetime resolution.
While doing so it also came apparent that we were not actually lowering lifetime outlives relationships within lifetime parameter declaration bounds, so this fixes that.
