# Function core::intrinsics::rintf64

source ·

    pub unsafe extern "rust-intrinsic" fn rintf64(x: f64) -> f64

🔬This is a nightly-only experimental API. (`core_intrinsics`)
Expand description

Returns the nearest integer to an `f64`. Changing the rounding mode is not possible in Rust, so this rounds half-way cases to the number with an even least significant digit.

May raise an inexact floating-point exception if the argument is not an integer. However, Rust assumes floating-point exceptions cannot be observed, so these exceptions cannot actually be utilized from Rust code. In other words, this intrinsic is equivalent in behavior to `nearbyintf64` and `roundevenf64`.

The stabilized version of this intrinsic is `f64::round_ties_even`