clippy::zero_divided_by_zero: constant division of `0.0` with `0.0` will always result in NaN

What you see

warning: constant division of `0.0` with `0.0` will always result in NaN
 --> main.rs:3:11
  |
3 | let nan = 0.0f32 / 0.0;
  |           ^^^^^^^^^^^^
  |
  = help: consider using `f32::NAN` if you would like a constant representing NaN
  = help: for further information visit https://rust-lang.github.io/rust-clippy/stable/index.html#zero_divided_by_zero
  = note: `#[warn(clippy::zero_divided_by_zero)]` on by default

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?

It’s less readable than f32::NAN or f64::NAN.

Code that does something simple in a complicated way. Warns by default.

How to fix it

Clippy does not fix this one automatically. Change the code by hand:

Flagged

let nan = 0.0f32 / 0.0;

Write this instead

let nan = f32::NAN;

Turn it off, or on

Allow it where it does not fit your code, as narrowly as you can:

#[allow(clippy::zero_divided_by_zero)]
fn my_function() { /* ... */ }

[lints.clippy]
zero_divided_by_zero = "allow"

cargo clippy -- -A clippy::zero-divided-by-zero

The [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.