Clippy lints / Restriction
Clippy lint · Restriction · checked with Clippy 0.1.99
clippy::little_endian_bytes: use of `to_le_bytes`
What it meansChecks for the usage of the to_le_bytes method and/or the function from_le_bytes. It is in the restriction group and off by default.
What you see
warning: use of `to_le_bytes` --> main.rs:3:15 | 3 | let _x = 2i32.to_le_bytes(); | ^^^^^^^^^^^ | = help: for further information visit https://rust-lang.github.io/rust-clippy/stable/index.html#little_endian_bytes = note: requested on the command line with `-W clippy::little-endian-bytes` help: convert to native endian | 3 - let _x = 2i32.to_le_bytes(); 3 + let _x = 2i32.to_ne_bytes(); | help: convert to big endian | 3 - let _x = 2i32.to_le_bytes(); 3 + let _x = 2i32.to_be_bytes(); |
Real output of Clippy 0.1.99 (Rust 1.99) on the example below. Names and line numbers in yours will differ.
Does it matter?
To ensure use of big-endian or the target’s endianness rather than little-endian.
Lints that forbid language features for specific codebases (no unwrap, no indexing...). Off by default; pick them one by one, never the whole group.
How to fix it
Clippy does not fix this one automatically (its suggestion may change behaviour, so it only shows it). Change the code by hand:
Flagged
let _x = 2i32.to_le_bytes();
let _y = 2i64.to_le_bytes();
Turn it off, or on
It is off by default. To use it, set it to warn or deny:
Whole crate (Cargo.toml)
[lints.clippy]
little_endian_bytes = "warn"In code
#![warn(clippy::little_endian_bytes)]One run
cargo clippy -- -W clippy::little-endian-bytesThe [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 the usage of the to_le_bytes method and/or the function from_le_bytes.
Why restrict this?
To ensure use of big-endian or the target’s endianness rather than little-endian.
Example
let _x = 2i32.to_le_bytes();
let _y = 2i64.to_le_bytes();
From the Clippy lint list (0.1.99), part of the Rust project, MIT or Apache-2.0. Official entry.
Related lints
- unwrap_usedChecks for .unwrap() or .unwrap_err() calls on Results and .unwrap() call on Options
- module_name_repetitionsDetects public item names that are prefixed or suffixed by the containing public module’s name
- expect_usedChecks for .expect() or .expect_err() calls on Results and .expect() call on Options
- large_include_fileChecks for the inclusion of large files via include_bytes!() or include_str!()
- let_underscore_must_usenon-binding `let` on an expression with `#[must_use]` type
- let_underscore_untypednon-binding `let` without a type annotation
- lossy_float_literalliteral cannot be represented as the underlying type without loss of precision
- map_err_ignore`map_err(|_|...` wildcard pattern discards the original error
- map_with_unused_argument_over_rangesmap of a closure that does not depend on its parameter over a range
All 847 Clippy lints · Rust compiler errors · Cargo.toml checker
Up next
Related lintclippy::unwrap_usedChecks for .unwrap() or .unwrap_err() calls on Results and .unwrap() call on OptionsRead it next →Did this answer your question?