1 files changed, 17 insertions, 0 deletions
diff --git a/tests/ui/unit.rs b/tests/ui/unit.rs
new file mode 100644
index 000000000..4f2dd4194
--- /dev/null
+++ b/tests/ui/unit.rs
@@ -0,0 +1,17 @@
+// run-pass
+
+#![allow(unused_assignments)]
+#![allow(unknown_lints)]
+// pretty-expanded FIXME #23616
+
+#![allow(unused_variables)]
+#![allow(dead_assignment)]
+
+fn f(u: ()) { return u; }
+
+pub fn main() {
+    let u1: () = ();
+    let mut u2: () = f(u1);
+    u2 = ();
+    return ();
+}