clobber error

#![feature(asm)]
use std::process::exit;

#[inline(never)]
fn main() {
    let a = Vec::from(&BUF[..]);
    let b: i64;
    let c = seed();
    let c = c.0 * c.1 * c.2 * c.3;

    let overwrite: i64;

    // seed the stack
    unsafe { asm!(
        "mov rdx, 1"
        : "={rdx}"(overwrite)
        ::: "intel", "volatile")}

    unsafe { asm!(
        "call rax"
        : "={rax}"(b)
        : "{rax}"(a.as_ptr().offset(4)) , "{rcx}"(c)
        : "{rdx}", "{memory}", "{c}c"
        : "intel", "volatile"
    ) };

    let c: i64;

    unsafe { asm!(
        "mov rax, rdx"
        : "={rax}"(c)
        : "{rdx}"(overwrite)
        :: "intel", "volatile"
    ) };

    exit((b * c) as i32);
}

#[inline(never)]
fn seed() -> (u8, u8, u8, u8) {
    let a = 1u8;
    (&a as *const u8 as u8,
     &a as *const u8 as u8,
     &a as *const u8 as u8,
     &a as *const u8 as u8)
}

// this is "00 00 00 00 mov rax, -1; ret". of course as this does not get in executable memory it would just fault if you'd actually run this.
const BUF: [u8; 12] = [0, 0, 0, 0, 0x48, 0xC7, 0xC0, 0xFF, 0xFF, 0xFF, 0xFF, 0xC3];