extern crate memmap;

use memmap::MmapOptions;

fn main() -> Result<(), std::io::Error> {
    let data: Vec<u8> = vec![184, 164, 1, 0, 0, 195];

    let mut mmap = MmapOptions::new().len(data.len()).map_anon()?;
    mmap.copy_from_slice(data.as_slice());
    // works
    let mmap2 = mmap.make_exec()?;
    let testfn = unsafe { std::mem::transmute::<*const u8, extern "C" fn() -> i32>(mmap2.as_ptr()) };
    // doesn't work
    // let testfn = unsafe { std::mem::transmute::<*const u8, extern "C" fn() -> i32>(mmap.make_exec()?.as_ptr()) };
    println!("{}", testfn());
    Ok(())
}