rust/compiler/rustc_lint
bors 788c98df59 Auto merge of #111818 - Urgau:uplift_cmp_nan, r=cjgillot
Uplift `clippy::cmp_nan` lint

This PR aims at uplifting the `clippy::cmp_nan` lint into rustc.

## `invalid_nan_comparisons`

~~(deny-by-default)~~ (warn-by-default)

The `invalid_nan_comparisons` lint checks comparison with `f32::NAN` or `f64::NAN` as one of the operand.

### Example

```rust,compile_fail
let a = 2.3f32;
if a == f32::NAN {}
```

### Explanation

NaN does not compare meaningfully to anything – not even itself – so those comparisons are always false.

-----

Mostly followed the instructions for uplifting a clippy lint described here: https://github.com/rust-lang/rust/pull/99696#pullrequestreview-1134072751

`@rustbot` label: +I-lang-nominated
r? compiler
2023-06-10 12:47:51 +00:00
..
src Auto merge of #111818 - Urgau:uplift_cmp_nan, r=cjgillot 2023-06-10 12:47:51 +00:00
Cargo.toml Add rustc_fluent_macro to decouple fluent from rustc_macros 2023-04-18 18:56:22 +00:00
messages.ftl Uplift improved version of clippy::cmp_nan to rustc 2023-06-10 11:12:55 +02:00