1 files changed, 60 insertions, 0 deletions
diff --git a/tests/ui/union/union-drop.rs b/tests/ui/union/union-drop.rs
new file mode 100644
index 00000000000..c3d7d41ca35
--- /dev/null
+++ b/tests/ui/union/union-drop.rs
@@ -0,0 +1,60 @@
+// run-pass
+// revisions: mirunsafeck thirunsafeck
+// [thirunsafeck]compile-flags: -Z thir-unsafeck
+
+#![allow(dead_code)]
+#![allow(unused_variables)]
+
+// Drop works for union itself.
+
+#[derive(Copy, Clone)]
+struct S;
+
+union U {
+    a: u8
+}
+
+union W {
+    a: S,
+}
+
+union Y {
+    a: S,
+}
+
+impl Drop for U {
+    fn drop(&mut self) {
+        unsafe { CHECK += 1; }
+    }
+}
+
+impl Drop for W {
+    fn drop(&mut self) {
+        unsafe { CHECK += 1; }
+    }
+}
+
+static mut CHECK: u8 = 0;
+
+fn main() {
+    unsafe {
+        assert_eq!(CHECK, 0);
+        {
+            let u = U { a: 1 };
+        }
+        assert_eq!(CHECK, 1); // 1, dtor of U is called
+        {
+            let w = W { a: S };
+        }
+        assert_eq!(CHECK, 2); // 2, dtor of W is called
+        {
+            let y = Y { a: S };
+        }
+        assert_eq!(CHECK, 2); // 2, Y has no dtor
+        {
+            let u2 = U { a: 1 };
+            std::mem::forget(u2);
+        }
+        assert_eq!(CHECK, 2); // 2, dtor of U *not* called for u2
+    }
+}