#![allow(dead_code, deprecated, unused_variables, unused_mut)]
use std::slice;
/// Sum the elements of an FFI slice.
///
/// # Safety
///
/// If ptr is not NULL, it must be correctly aligned and
/// point to `len` initialized items of type `f32`.
unsafe extern "C" fn sum_slice(ptr: *const f32, len: usize) -> f32 {
    let data = if ptr.is_null() {
        &[]
    } else {
        unsafe { slice::from_raw_parts(ptr, len) }
    };
    data.into_iter().sum()
}
fn main() {
    let ptr = std::ptr::null();
    let len = 0;
    assert_eq!(unsafe { sum_slice(ptr, len) }, 0.0);
}