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//! Ensure we catch UB due to writing through a shared reference.
#![allow(invalid_reference_casting)]
use std::mem;
use std::cell::UnsafeCell;
const WRITE_AFTER_CAST: () = unsafe {
let mut x = 0;
let ptr = &x as *const i32 as *mut i32;
*ptr = 0; //~ERROR: evaluation of constant value failed
//~| immutable
};
const WRITE_AFTER_TRANSMUTE: () = unsafe {
let mut x = 0;
let ptr: *mut i32 = mem::transmute(&x);
*ptr = 0; //~ERROR: evaluation of constant value failed
//~| immutable
};
// it's okay when there is interior mutability;
const WRITE_INTERIOR_MUT: () = unsafe {
let x = UnsafeCell::new(0);
let ptr = &x as *const _ as *mut i32;
*ptr = 0;
};
fn main() {}
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