Add (back) `unsupported_calling_conventions` lint to reject more invalid calling conventions
This adds back the `unsupported_calling_conventions` lint that was removed in https://github.com/rust-lang/rust/pull/129935, in order to start the process of dealing with https://github.com/rust-lang/rust/issues/137018. Specifically, we are going for the plan laid out [here](https://github.com/rust-lang/rust/issues/137018#issuecomment-2672118326):
- thiscall, stdcall, fastcall, cdecl should only be accepted on x86-32
- vectorcall should only be accepted on x86-32 and x86-64
The difference to the status quo is that:
- We stop accepting stdcall, fastcall on targets that are windows && non-x86-32 (we already don't accept these on targets that are non-windows && non-x86-32)
- We stop accepting cdecl on targets that are non-x86-32
- (There is no difference for thiscall, this was already a hard error on non-x86-32)
- We stop accepting vectorcall on targets that are windows && non-x86-*
Vectorcall is an unstable ABI so we can just make this a hard error immediately. The others are stable, so we emit the `unsupported_calling_conventions` forward-compat lint. I set up the lint to show up in dependencies via cargo's future-compat report immediately, but we could also make it show up just for the local crate first if that is preferred.
try-job: i686-msvc-1
try-job: x86_64-msvc-1
try-job: test-various
Make the `dangerous_implicit_autorefs` lint deny-by-default
I intended for the `dangerous_implicit_autorefs` lint to be deny-by-default, the [T-lang nomination comment](https://github.com/rust-lang/rust/pull/123239#issuecomment-2727551097) even clearly mentioned deny-by-default, but somehow I and other missed that it is only warn-by-default.
I think the lint should still be deny-by-default as the implicit aliasing requirements can be quite dangerous.
In any-case, opening this PR for T-lang awareness.
`@rustbot` label +I-lang-nominated +T-lang
r? `@traviscross`
Replace some `Option<Span>` with `Span` and use DUMMY_SP instead of None
Turns out many locations actually have a span available that we could use, so I used it
Add a new `mismatched-lifetime-syntaxes` lint
The lang-team [discussed this](https://hackmd.io/nf4ZUYd7Rp6rq-1svJZSaQ) and I attempted to [summarize](https://github.com/rust-lang/rust/pull/120808#issuecomment-2701863833) their decision. The summary-of-the-summary is:
- Using two different kinds of syntax for elided lifetimes is confusing. In rare cases, it may even [lead to unsound code](https://github.com/rust-lang/rust/issues/48686)! Some examples:
```rust
// Lint will warn about these
fn(v: ContainsLifetime) -> ContainsLifetime<'_>;
fn(&'static u8) -> &u8;
```
- Matching up references with no lifetime syntax, references with anonymous lifetime syntax, and paths with anonymous lifetime syntax is an exception to the simplest possible rule:
```rust
// Lint will not warn about these
fn(&u8) -> &'_ u8;
fn(&'_ u8) -> &u8;
fn(&u8) -> ContainsLifetime<'_>;
```
- Having a lint for consistent syntax of elided lifetimes will make the [future goal](https://github.com/rust-lang/rust/issues/91639) of warning-by-default for paths participating in elision much simpler.
---
This new lint attempts to accomplish the goal of enforcing consistent syntax. In the process, it supersedes and replaces the existing `elided-named-lifetimes` lint, which means it starts out life as warn-by-default.
Rollup of 9 pull requests
Successful merges:
- rust-lang/rust#141554 (Improve documentation for codegen options)
- rust-lang/rust#141817 (rustc_llvm: add Windows system libs only when cross-compiling from Wi…)
- rust-lang/rust#141843 (Add `visit_id` to ast `Visitor`)
- rust-lang/rust#141881 (Subtree update of `rust-analyzer`)
- rust-lang/rust#141898 ([rustdoc-json] Implement PartialOrd and Ord for rustdoc_types::Id)
- rust-lang/rust#141921 (Disable f64 minimum/maximum tests for arm 32)
- rust-lang/rust#141930 (Enable triagebot `[concern]` functionality)
- rust-lang/rust#141936 (Decouple "reporting in deps" from `FutureIncompatibilityReason`)
- rust-lang/rust#141949 (move `test-float-parse` tool into `src/tools` dir)
r? `@ghost`
`@rustbot` modify labels: rollup
Decouple "reporting in deps" from `FutureIncompatibilityReason`
The reason should just be it -- the reason. It never felt right to me that it was also responsible for whatever we include the warning in cargo's reports.
It gets especially unruly if you want to add non-`FutureReleaseError*` warnings which are included in the reports.
I just added a field to `FutureIncompatibleInfo` to control whatever the diagnostic is included in the cargo's reports.
Add `visit_id` to ast `Visitor`
This helps with efforts to deduplicate the `MutVisitor` and the `Visitor` code. All users of `Visitor`'s methods that have extra `NodeId` as parameters really just want to visit the id on its own.
Also includes some methods deduplicated and cleaned up as a result of this change.
r? oli-obk
`UsePath` contains a `SmallVec<[Res; 3]>`. This holds up to three `Res`
results, one per namespace (type, value, or macro). `lower_import_res`
takes a `PerNS<Option<Res<NodeId>>>` result and lowers it into the
`SmallVec`. This is pretty weird. The input `PerNS` makes it clear which
`Res` belongs to which namespace, but the `SmallVec` throws that
information away.
And code that operates on the `SmallVec` tends to use iteration (or even
just grabbing the first entry!) without knowing which namespace the
`Res` belongs to. Even weirder! Also, `SmallVec` is an overly flexible
type to use here, because it can contain any number of elements (even
though it's optimized for 3 in this case).
This commit changes `UsePath` so it also contains a
`PerNS<Option<Res<HirId>>>`. This type preserves more information and is
more self-documenting. The commit also changes a lot of the use sites to
access the result for a particular namespace. E.g. if you're looking up
a trait, it will be in the `Res` for the type namespace if it's present;
it's silly to look in the `Res` for the value namespace or macro
namespace. Overall I find the new code much easier to understand.
However, some use sites still iterate. These now use `present_items`
because that filters out the `None` results.
Also, `redundant_pub_crate.rs` gets a bigger change. A
`UseKind:ListStem` item gets no `Res` results, which means the old `all`
call in `is_not_macro_export` would succeed (because `all` succeeds on
an empty iterator) and the `ListStem` would be ignored. This is what we
want, but was more by luck than design. The new code detects `ListStem`
explicitly. The commit generalizes the name of that function
accordingly.
Finally, the commit also removes the `use_path` arena, because
`PerNS<Option<Res>>` impls `Copy` (unlike `SmallVec`) and it can be
allocated in the arena shared by all `Copy` types.
This helps with efforts to deduplicate the `MutVisitor` and the
`Visitor` code. All users of `Visitor`'s methods that have extra
`NodeId` as parameters really just want to visit the id on its
own.
Also includes some methods deduplicated and cleaned up as
a result of this change.
Report text_direction_codepoint_in_literal when parsing
The lint is now reported in code that gets removed/modified/duplicated by macro expansion, and spans are more accurate so we don't get ICEs from trying to split a span in the middle of a character.
This removes support for lint level attributes for `text_direction_codepoint_in_literal` except at the crate level, I don't think that there's an easy way around this when the lint can be reported on code that's removed by `cfg` or that is only in the input of a macro.
Fixes#140281
Use `cfg_attr_trace` in AST with a placeholder attribute for accurate suggestion
In rust-lang/rust#138515, we insert a placeholder attribute so that checks for attributes can still know about the placement of `cfg` attributes. When we suggest removing items with `cfg_attr`s (fixrust-lang/rust#56328) and make them verbose. We tweak the wording of the existing "unused `extern crate`" lint.
```
warning: unused `extern crate`
--> $DIR/removing-extern-crate.rs:9:1
|
LL | extern crate removing_extern_crate as foo;
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ unused
|
note: the lint level is defined here
--> $DIR/removing-extern-crate.rs:6:9
|
LL | #![warn(rust_2018_idioms)]
| ^^^^^^^^^^^^^^^^
= note: `#[warn(unused_extern_crates)]` implied by `#[warn(rust_2018_idioms)]`
help: remove the unused `extern crate`
|
LL - #[cfg_attr(test, macro_use)]
LL - extern crate removing_extern_crate as foo;
|
```
r? `@petrochenkov`
try-job: x86_64-gnu-aux
Specifically `TyAlias`, `Enum`, `Struct`, `Union`. So the fields match
the textual order in the source code.
The interesting part of the change is in
`compiler/rustc_hir/src/hir.rs`. The rest is extremely mechanical
refactoring.
PR 138515, we insert a placeholder attribute so that checks for attributes can still know about the placement of `cfg` attributes. When we suggest removing items with `cfg_attr`s (fix Issue 56328) and make them verbose. We tweak the wording of the existing "unused `extern crate`" lint.
```
warning: unused extern crate
--> $DIR/removing-extern-crate.rs:9:1
|
LL | extern crate removing_extern_crate as foo;
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ unused
|
note: the lint level is defined here
--> $DIR/removing-extern-crate.rs:6:9
|
LL | #![warn(rust_2018_idioms)]
| ^^^^^^^^^^^^^^^^
= note: `#[warn(unused_extern_crates)]` implied by `#[warn(rust_2018_idioms)]`
help: remove the unused `extern crate`
|
LL - #[cfg_attr(test, macro_use)]
LL - extern crate removing_extern_crate as foo;
LL +
|
```
Make two transmute-related MIR lints into HIR lint
Make `PTR_TO_INTEGER_TRANSMUTE_IN_CONSTS` (rust-lang/rust#130540) and `UNNECESSARY_TRANSMUTES` (rust-lang/rust#136083) into "normal" HIR-based lints.
Funny enough this came up in the review of the latter (https://github.com/rust-lang/rust/pull/136083#issuecomment-2614301413), but I guess it just was overlooked.
But anywyas, there's no reason for these to be MIR lints; in fact, it makes the suggestions for them a bit more complicated than necessary.
Note that there's probably a few more simplifications and improvements to be done here. Follow-ups can be done in a separate PR, especially if they're about the messaging and suggestions themselves, which I didn't write.
Make check-cfg diagnostics work in `#[doc(cfg(..))]`
This PR makes it so that the check-cfg `unexpected_cfgs` lint, is correctly emitted in `rustdoc`'s `#[doc(cfg(..))]`.
This is achieved by adding a custom trait to `cfg_matches` (the method that emits the lint) which permits `rustc` and `rustdoc` to each have their way to emitting lints (via buffered lints/AST for `rustc` and via `TyCtxt`/HIR for `rustdoc`).
The reason this is required is because buffered lints operates on the AST but `rustdoc` uses the HIR and by the time `rustdoc` calls `cfg_matches` we are way passed the point where buffered lints have been drain and emitted.
Best reviewed commit by commit.
r? `@jieyouxu` (for the compiler part)
r? `@GuillaumeGomez` (for the rustdoc part)
Rename `{GenericArg,Term}::unpack()` to `kind()`
A well-deserved rename IMO.
r? `@oli-obk` or `@lcnr` (or anyone)
cc `@rust-lang/types,` but I'd be surprised if this is controversial.
Improve `ambiguous_wide_pointer_comparisons` lint compare diagnostics
This PR improves the `ambiguous_wide_pointer_comparisons` lint compare diagnostics: `cmp`/`partial_cmp`, but also the operators `<`/`>`/`>=`/`<=`, by:
1. removing the reference to `std::ptr::addr_eq` which only works for equality
2. and adding an `#[expect]` suggestion for keeping the current behavior
Fixesrust-lang/rust#141510
Fix `unused_braces` lint suggestion when encountering attributes
This PR fixes the `unused_braces` lint suggestion when encountering attributes by not removing them in the suggestion.
Fixesrust-lang/rust#141549
make `rustc_attr_parsing` less dominant in the rustc crate graph
It has/had a glob re-export of `rustc_attr_data_structures`, which is a crate much lower in the graph, and a lot of crates were using it *just* (or *mostly*) for that re-export, while they can rely on `rustc_attr_data_structures` directly.
Previous graph:
Graph with this PR:
The first commit keeps the re-export, and just changes the dependency if possible. The second commit is the "breaking change" which removes the re-export, and "explicitly" adds the `rustc_attr_data_structures` dependency where needed. It also switches over some src/tools/*.
The second commit is actually a lot more involved than I expected. Please let me know if it's a better idea to back it out and just keep the first commit.
Stage0 bootstrap update
This PR [follows the release process](https://forge.rust-lang.org/release/process.html#master-bootstrap-update-tuesday) to update the stage0 compiler.
The only thing of note is 58651d1b31, which was flagged by clippy as a correctness fix. I think allowing that lint in our case makes sense, but it's worth to have a second pair of eyes on it.
r? `@Mark-Simulacrum`
Use span before macro expansion in lint for-loops-over-falibles
Fixes#140747
I think there are going to be a lot of cases where macros are expanded in the compiler resulting in span offsets, and I'd like to know how that's typically handled. Does it have to be handled specially every time?
The documentation is talking about other way using only raw pointers, but the example was use `std::slice::from_raw_parts_mut` which also create a reference. `std::ptr::slice_from_raw_parts_mut` should be used instead, and it also highlights the benefit of raw pointer manipulation compared to dereference, as the function doesn't need to be unsafe anymore.
Moreover, [`unsafe_op_in_unsafe_fn`](https://doc.rust-lang.org/edition-guide/rust-2024/unsafe-op-in-unsafe-fn.html) warning has been enabled since Edition 2024, so I've updated the examples to use unsafe blocks.
