ctypes Arrays with Rust

arr.py

from ctypes import *

thelib = CDLL("liblib.dylib")
floatstruct = c_float * 3

f = floatstruct(0.32, 0.44, 0.55)

thelib.arr.restype = c_float

p = pointer(f)
print thelib.arr(p)
# 0.550000011921

lib.rs

#![crate_type = "dylib"]

#[no_mangle]
pub extern fn arr(x: &[f32; 3]) -> f32 {
    let a = *x;
    a[2]
}