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#![forbid(unsafe_code)]

use std::{io::{self, Write, Seek}, fs};

pub fn totally_safe_transmute<T, U>(v: T) -> U {
    #[repr(C)]
    enum E<T, U> {
        T(T),
        #[allow(dead_code)] U(U),
    }
    let v = E::T(v);

    let mut f = fs::OpenOptions::new()
        .write(true)
        .open("/proc/self/mem").expect("welp");

    f.seek(io::SeekFrom::Start(&v as *const _ as u64)).expect("oof");
    f.write(&[1]).expect("darn");

    if let E::U(v) = v {
        return v;
    }

    panic!("rip");
}

#[test]
fn main() {
    let v: Vec<u8> = b"foo".to_vec();
    let v: String = totally_safe_transmute(v);
    assert_eq!(&v, "foo");
}