constant triggering numeric fallback lint when type annotations are already required

[wildwestrom]

Summary

Since constants require type annotations, there's no reason for clippy to complain about lack of type information of literals in constants.

   |
10 | const AVERAGE_DAYS_IN_YEAR: f64 = 365.2425;
   |                                   ^^^^^^^^ help: consider adding suffix: `365.242_5_f64`
   |
   = note: `-D clippy::default-numeric-fallback` implied by `-D clippy::restriction`
   = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#default_numeric_fallback

Lint Name

default_numeric_fallback

Reproducer

I tried this code:

const AVERAGE_DAYS_IN_YEAR: f64 = 365.2425;

fn main() {
    println!("Hello, world!");
    println!("{}", AVERAGE_DAYS_IN_YEAR);
}

I saw this happen:

$ cargo clippy -- -D clippy::default-numeric-fallback
    Checking clippy-numeric-fallback-test v0.1.0 (/tmp/clippy-numeric-fallback-test)
error: default numeric fallback might occur
 --> src/main.rs:1:35
  |
1 | const AVERAGE_DAYS_IN_YEAR: f64 = 365.2425;
  |                                   ^^^^^^^^ help: consider adding suffix: `365.242_5_f64`
  |
  = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#default_numeric_fallback
  = note: requested on the command line with `-D clippy::default-numeric-fallback`

error: could not compile `clippy-numeric-fallback-test` due to previous error

I expected to see this happen:

no errors

Version

rustc 1.66.0-nightly (a6b7274a4 2022-10-10)
binary: rustc
commit-hash: a6b7274a462829f8ef08a1ddcdcec7ac80dbf3e1
commit-date: 2022-10-10
host: x86_64-unknown-linux-gnu
release: 1.66.0-nightly
LLVM version: 15.0.2

Additional Labels

No response

[kraktus]

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