1 files changed, 38 insertions, 0 deletions
diff --git a/tests/ui/dropck/dropck-union.rs b/tests/ui/dropck/dropck-union.rs
new file mode 100644
index 000000000..5a9965db5
--- /dev/null
+++ b/tests/ui/dropck/dropck-union.rs
@@ -0,0 +1,38 @@
+use std::cell::Cell;
+use std::ops::Deref;
+use std::mem::ManuallyDrop;
+
+union Wrap<T> { x: ManuallyDrop<T> }
+
+impl<T> Drop for Wrap<T>  {
+    fn drop(&mut self) {
+        unsafe { std::ptr::drop_in_place(&mut *self.x as *mut T); }
+    }
+}
+
+impl<T> Wrap<T> {
+    fn new(x: T) -> Self {
+        Wrap { x: ManuallyDrop::new(x) }
+    }
+}
+
+impl<T> Deref for Wrap<T> {
+    type Target = T;
+    #[inline]
+    fn deref(&self) -> &Self::Target {
+        unsafe {
+            &self.x
+        }
+    }
+}
+
+struct C<'a>(Cell<Option<&'a C<'a>>>);
+
+impl<'a> Drop for C<'a> {
+    fn drop(&mut self) {}
+}
+
+fn main() {
+    let v : Wrap<C> = Wrap::new(C(Cell::new(None)));
+    v.0.set(Some(&v)); //~ ERROR: `v` does not live long enough
+}