Clippy lints / Complexity
Clippy lint · Complexity · checked with Clippy 0.1.99
clippy::transmutes_expressible_as_ptr_casts: Checks for transmutes that could be a pointer cast
What it meansChecks for transmutes that could be a pointer cast. It is in the complexity group and warns by default.
Does it matter?
Readability. The code tricks people into thinking that something complex is going on.
Code that does something simple in a complicated way. Warns by default.
How to fix it
Clippy can fix this one for you: run cargo clippy --fix (add --allow-dirty if you have uncommitted changes). Review the diff before you commit.
Flagged
unsafe { std::mem::transmute::<*const [i32], *const [u16]>(p) };
Write this instead
p as *const [u16];
Turn it off, or on
Allow it where it does not fit your code, as narrowly as you can:
On one item
#[allow(clippy::transmutes_expressible_as_ptr_casts)]
fn my_function() { /* ... */ }Whole crate (Cargo.toml)
[lints.clippy]
transmutes_expressible_as_ptr_casts = "allow"One run
cargo clippy -- -A clippy::transmutes-expressible-as-ptr-castsThe [lints] table needs Rust 1.74 or newer. In a workspace, put it under [workspace.lints.clippy] and add [lints] workspace = true to each member.
Clippy's own documentation
What it does
Checks for transmutes that could be a pointer cast.
Why is this bad?
Readability. The code tricks people into thinking that something complex is going on.
Example
unsafe { std::mem::transmute::<*const [i32], *const [u16]>(p) };
Use instead:
p as *const [u16];
From the Clippy lint list (0.1.99), part of the Rust project, MIT or Apache-2.0. Official entry.
Related lints
- too_many_argumentsChecks for functions with too many parameters
- clone_on_copyusing `clone` on type `u64` which implements the `Copy` trait
- type_complexityChecks for types used in structs, parameters and let declarations above a certain complexity threshold
- transmute_int_to_booltransmute from a `u8` to a `bool`
- transmute_int_to_non_zeroChecks for transmutes from T to NonZero<T>, and suggests the new_unchecked method instead
- transmute_ptr_to_refChecks for transmutes from a pointer to a reference
- unit_argChecks for passing a unit value as an argument to a function without using a unit literal (())
- unnecessary_castcasting integer literal to `i32` is unnecessary
All 847 Clippy lints · Rust compiler errors · Cargo.toml checker
Up next
Related lintclippy::too_many_argumentsChecks for functions with too many parametersRead it next →Did this answer your question?