It's common to import dependencies from the sysroot via `extern crate`
rather than use an explicit cargo dependency, when it's necessary to use
the same dependency version as used by rustc itself. However, this is
dangerous for crates.io crates, since rustc may not pull in the
dependency on some targets, or may pull in multiple versions. In both
cases, the `extern crate` fails to resolve.
To address this, re-export all such dependencies from the appropriate
`rustc_*` crates, and use this alias from crates which would otherwise
need to use `extern crate`.
This lint aims at detecting unusual names used in Clippy source code,
such as `appl` or `application` for a `rustc_errors::Applicability`
variable, instead of `app` and `applicability` which are commonly used
throughout Clippy.
This helps maintaining the consistency of the Clippy source code.
Volatile reads and writes to non-primitive types are not well-defined,
and can cause problems.
Fixesrust-lang/rust-clippy#15529
changelog: [`volatile_composites`]: Lint when read/write_volatile is
used on composite types
(structs, arrays, etc) as their semantics are not well defined.
First commit treats all constants containing a macro call as non-local
and renames `eval_simple` to be a little clearer.
Second commit removes `CoreConstant` and treats most of them as though
they were local. A couple of the constants like `usize::MAX` are treated
as non-local as different targets may have different values.
`const_is_empty` will now ignore non-local constants since there's no
guarantee that they are the same across all targets/features/versions.
The third commit just changes some `eval` calls to `eval_local`. Most of
these were style lints which shouldn't be assuming the value of a
constant won't ever change.
changelog: none
Starting with Rust version 1.82.0, the compiler generates similar code
with and without the `with_ref` cfg:
```rust
fn f(x: impl IntoIterator<Item = String>) {
for y in x { println!("{y}"); }
}
fn main() {
#[cfg(with_ref)]
let a = ["foo", "bar"].iter().map(|&s| s.to_string());
#[cfg(not(with_ref))]
let a = ["foo", "bar"].iter().map(|s| s.to_string());
f(a);
}
```
The generated code is strictly identical with `-O`, and identical modulo
some minor reordering without.
changelog: [`inefficient_to_string`]: do not trigger for Rust ≥ 1.82.0
Starting with Rust version 1.82.0, the compiler generates similar code with
and without the `with_ref` cfg:
```rust
fn f(x: impl IntoIterator<Item = String>) {
for y in x { println!("{y}"); }
}
fn main() {
#[cfg(with_ref)]
let a = ["foo", "bar"].iter().map(|&s| s.to_string());
#[cfg(not(with_ref))]
let a = ["foo", "bar"].iter().map(|s| s.to_string());
f(a);
}
```
The generated code is strictly identical with `-O`, and identical modulo
some minor reordering without.
This might be due to a low edition (< 2024) or too low a MSRV. In this
case, we will suggest only `match`.
Fixesrust-lang/rust-clippy#15744
changelog: [`unnecessary_unwrap`]: do not suggest using `if let` chains
if this is not supported with the current edition or MSRV
changelog:[`collapsible_if`]: Do not suggest using `if let` if this is
not supported with the current edition or MSRV
While looking into
https://github.com/rust-lang/rust-clippy/issues/15569, I stumbled upon
`clippy_utils::ptr`.
This module was created in
https://github.com/rust-lang/rust-clippy/pull/2117, to share the logic
from `ptr_arg` with `needless_pass_by_value`. But then later,
https://github.com/rust-lang/rust-clippy/pull/8409 removed the use of
the logic from `ptr_arg`, which left `needless_pass_by_value` as the
only user of this module.
Still, I wanted to try to add docs to the module, but the two functions
looked all too specific, so I thought it'd be better to just move them
to `needless_pass_by_value`, in the hopes that whoever is looking at
that lint will hopefully have enough context to understand what those
functions are doing.
changelog: none
