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// run-pass
// aux-build:custom.rs
// aux-build:custom-as-global.rs
// aux-build:helper.rs
// no-prefer-dynamic
#![feature(allocator_api)]
extern crate custom;
extern crate custom_as_global;
extern crate helper;
use std::alloc::{alloc, dealloc, GlobalAlloc, System, Layout};
use std::sync::atomic::{AtomicUsize, Ordering};
static GLOBAL: custom::A = custom::A(AtomicUsize::new(0));
fn main() {
unsafe {
let n = custom_as_global::get();
let layout = Layout::from_size_align(4, 2).unwrap();
// Global allocator routes to the `custom_as_global` global
let ptr = alloc(layout.clone());
helper::work_with(&ptr);
assert_eq!(custom_as_global::get(), n + 1);
dealloc(ptr, layout.clone());
assert_eq!(custom_as_global::get(), n + 2);
// Usage of the system allocator avoids all globals
let ptr = System.alloc(layout.clone());
helper::work_with(&ptr);
assert_eq!(custom_as_global::get(), n + 2);
System.dealloc(ptr, layout.clone());
assert_eq!(custom_as_global::get(), n + 2);
// Usage of our personal allocator doesn't affect other instances
let ptr = GLOBAL.alloc(layout.clone());
helper::work_with(&ptr);
assert_eq!(custom_as_global::get(), n + 2);
assert_eq!(GLOBAL.0.load(Ordering::SeqCst), 1);
GLOBAL.dealloc(ptr, layout);
assert_eq!(custom_as_global::get(), n + 2);
assert_eq!(GLOBAL.0.load(Ordering::SeqCst), 2);
}
}
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