1 files changed, 47 insertions, 0 deletions
diff --git a/tests/ui/allocator/xcrate-use2.rs b/tests/ui/allocator/xcrate-use2.rs
new file mode 100644
index 000000000..d8478fb5e
--- /dev/null
+++ b/tests/ui/allocator/xcrate-use2.rs
@@ -0,0 +1,47 @@
+// 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);
+    }
+}