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//@run-pass
#![feature(sync_unsafe_cell)]
use std::cell::SyncUnsafeCell;
use std::ptr;
#[repr(C)]
struct SyncPtr {
foo: *mut u32,
}
unsafe impl Sync for SyncPtr {}
static mut STATIC: u32 = 42;
static INTERIOR_MUTABLE_STATIC: SyncUnsafeCell<u32> = SyncUnsafeCell::new(42);
// A static that mutably points to STATIC.
static PTR: SyncPtr = SyncPtr { foo: ptr::addr_of_mut!(STATIC) };
static INTERIOR_MUTABLE_PTR: SyncPtr =
SyncPtr { foo: ptr::addr_of!(INTERIOR_MUTABLE_STATIC) as *mut u32 };
fn main() {
let ptr = PTR.foo;
unsafe {
assert_eq!(*ptr, 42);
*ptr = 0;
assert_eq!(*PTR.foo, 0);
}
let ptr = INTERIOR_MUTABLE_PTR.foo;
unsafe {
assert_eq!(*ptr, 42);
*ptr = 0;
assert_eq!(*INTERIOR_MUTABLE_PTR.foo, 0);
}
}
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