tests: Test that `extern "C" fn` ptrs lint on slices
This seems to have slipped past the `improper_ctypes_definitions` lint at some point. I found similar tests but not one with this exact combination, so test the semi-unique combination.
Explain why `non_snake_case` is skipped for binary crates and cleanup tests
- Explain `non_snake_case` lint is skipped for bin crate names because binaries are not intended to be distributed or consumed like library crates (#45127).
- Coalesce the bunch of tests into a single one but with revisions, which is easier to compare the differences for `non_snake_case` behavior with respect to crate types.
Follow-up to #121749 with some more comments and test cleanup.
cc `@saethlin` who bumped into one of the tests and was confused why it was `only-x86_64-unknown-linux-gnu`.
try-job: dist-i586-gnu-i586-i686-musl
Add recursion limit to FFI safety lint
Fixes#130310
Now we check against `tcx.recursion_limit()` and raise an error if it the limit is reached instead of overflowing the stack.
Since #130025, the compiler don't ignore missing_docs when compiling the tests.
But there is now a false positive warning for every `#[test]`
For example, this code
```rust
//! Crate docs
fn just_a_test() {}
```
Would emit this warning when running `cargo test`
```
warning: missing documentation for a constant
--> src/lib.rs:5:1
|
4 | #[test]
| ------- in this procedural macro expansion
5 | fn just_a_test() {}
| ^^^^^^^^^^^^^^^^^^^
```
Enumerate lint expectations using AttrId
This PR implements the idea I outlined in https://github.com/rust-lang/rust/issues/127884#issuecomment-2240338547
We can uniquely identify a lint expectation `#[expect(lint0, lint1...)]` using the `AttrId` and the index of the lint inside the attribute. This PR uses this property in `check_expectations`.
In addition, this PR stops stashing expected diagnostics to wait for the unstable -> stable `LintExpectationId` mapping: if the lint is emitted with an unstable attribute, it must have been emitted by an `eval_always` query (like inside the resolver), so won't be loaded from cache. Decoding an `AttrId` from the on-disk cache ICEs, so we have no risk of accidentally checking an expectation.
Fixes https://github.com/rust-lang/rust/issues/127884
cc `@xFrednet`
Also emit `missing_docs` lint with `--test` to fulfil expectations
This PR removes the "test harness" suppression of the `missing_docs` lint to be able to fulfil `#[expect]` (expectations) as it is now "relevant".
I think the goal was to maybe avoid false-positive while linting on public items under `#[cfg(test)]` but with effective visibility we should no longer have any false-positive.
Another possibility would be to query the lint level and only emit the lint if it's of expect level, but that is even more hacky.
Fixes https://github.com/rust-lang/rust/issues/130021
try-job: x86_64-gnu-aux
Rewrite lint_expectations in a single pass.
This PR aims at reducing the perf regression from https://github.com/rust-lang/rust/pull/120924#issuecomment-2202486203 with drive-by simplifications.
Basically, instead of using the lint level builder, which is slow, this PR splits `lint_expectations` logic in 2:
- listing the `LintExpectations` is done in `shallow_lint_levels_on`, on a per-owner basis;
- building the unstable->stable expectation id map is done by iterating on attributes.
r? ghost for perf
Add a special case for `CStr`/`CString` in the `improper_ctypes` lint
Revives #120176. Just needed to bless a test and fix an argument, but seemed reasonable to me otherwise.
Instead of saying to "consider adding a `#[repr(C)]` or `#[repr(transparent)]` attribute to this struct", we now tell users to "Use `*const ffi::c_char` instead, and pass the value from `CStr::as_ptr()`" when the type involved is a `CStr` or a `CString`.
The suggestion is not made for `&mut CString` or `*mut CString`.
r? ``````@cjgillot`````` (since you were the reviewer of the original PR #120176, but feel free to reroll)
Fix handling of macro arguments within the `dropping_copy_types` lint
This PR fixes the handling of spans with different context (aka macro arguments) than the primary expression within the different `{drop,forget}ing_copy_types` and `{drop,forget}ing_references` lints.
<details>
<summary>Before</summary>
```
warning: calls to `std::mem::drop` with a value that implements `Copy` does nothing
--> drop_writeln.rs:5:5
|
5 | drop(writeln!(&mut msg, "test"));
| ^^^^^--------------------------^
| |
| argument has type `Result<(), std::fmt::Error>`
|
= note: `#[warn(dropping_copy_types)]` on by default
help: use `let _ = ...` to ignore the expression or result
--> /home/[..]/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/core/src/macros/mod.rs:688:9
|
68| let _ =
| ~~~~~~~
```
</details>
<details>
<summary>With this PR</summary>
```
warning: calls to `std::mem::drop` with a value that implements `Copy` does nothing
--> drop_writeln.rs:5:5
|
5 | drop(writeln!(&mut msg, "test"));
| ^^^^^--------------------------^
| |
| argument has type `Result<(), std::fmt::Error>`
|
= note: `#[warn(dropping_copy_types)]` on by default
help: use `let _ = ...` to ignore the expression or result
|
5 - drop(writeln!(&mut msg, "test"));
5 + let _ = writeln!(&mut msg, "test");
|
```
</details>
``````@rustbot`````` label +L-dropping_copy_types
Miscellaneous improvements to struct tail normalization
1. Make checks for foreign tails more accurate by normalizing the struct tail. I didn't write a test for this one.
2. Normalize when computing struct tail for `offset_of` for slice/str. This fixes the new solver only.
3. Normalizing when computing tails for disaligned reference check. This fixes both solvers.
r? lcnr
Instead of saying to "consider adding a `#[repr(C)]` or
`#[repr(transparent)]` attribute to this struct", we now tell users to
"Use `*const ffi::c_char` instead, and pass the value from
`CStr::as_ptr()`" when the type involved is a `CStr` or a `CString`.
Co-authored-by: Jieyou Xu <jieyouxu@outlook.com>
