RS.CLIPPY.BORROW_AS_PTR

Borrowing just to cast to a raw pointer

This checker is a Clippy lint created by The Rust Project Contributors. The documentation shown here is a copy of the original documentation for: borrow_as_ptr. Copyright ©2025 The Rust Team. All rights reserved.

What it does

Checks for the usage of &expr as *const T or &mut expr as *mut T, and suggest using &raw const or &raw mut instead.

Why is this bad?

This would improve readability and avoid creating a reference that points to an uninitialized value or unaligned place. Read the &raw explanation in the Reference for more information.

Example

let val = 1;
let p = &val as *const i32;

let mut val_mut = 1;
let p_mut = &mut val_mut as *mut i32;

Use instead:

let val = 1;
let p = &raw const val;

let mut val_mut = 1;
let p_mut = &raw mut val_mut;

Configuration

msrv: The minimum rust version that the project supports. Defaults to the rust-version field in Cargo.toml

(default: current version)