Rust suggests me use `compiler_builtins` 💀

[suprohub]

I tried this code:
https://github.com/suprohub/cos

I expected to see normal work, but
Instead, if i add in random place of my crate f64::PI, it suggests me this problema solution:

error[E0599]: no associated item named `PI` found for type `f64` in the current scope
  --> src/num.rs:77:14
   |
77 |         f64::PI;
   |              ^^ associated item not found in `f64`
   |
   = help: items from traits can only be used if the trait is in scope
help: trait `Float` which provides `PI` is implemented but not in scope; perhaps you want to import it
   |
 1 + use compiler_builtins::math::libm_math::support::float_traits::Float;
   |

No one of my crates use compiler builtins, and my Cargo.lock dont have compiler_builtins too.

Meta

rustc --version --verbose:

noviui@suprohub ~> rustc --version --verbose
rustc 1.90.0 (1159e78c4 2025-09-14)
binary: rustc
commit-hash: 1159e78c4747b02ef996e55082b704c09b970588
commit-date: 2025-09-14
host: x86_64-unknown-linux-gnu
release: 1.90.0
LLVM version: 20.1.8
noviui@suprohub ~> 

i use latest nightly btw.

This issue goes from this issue: #142676.

[JonathanBrouwer]

MCVE using the ufmt crate v0.2:

use ufmt::derive::uDebug;

pub fn aa() {
    f64::PI;
}

The use statement is important here
@rustbot claim

[JonathanBrouwer]

Final MCVE:
ufmt/src/lib.rs

#![no_std]
pub fn apple() { }

src/lib.rs

#![no_std]
use ufmt::apple;
pub fn aa() {
    f64::PI;
}

.cargo/config.toml

[unstable]
build-std = ["core"]