1 files changed, 18 insertions, 0 deletions
diff --git a/tests/ui/expr-copy.rs b/tests/ui/expr-copy.rs
new file mode 100644
index 00000000000..1c6ae03810f
--- /dev/null
+++ b/tests/ui/expr-copy.rs
@@ -0,0 +1,18 @@
+// run-pass
+
+fn f(arg: &mut A) {
+    arg.a = 100;
+}
+
+#[derive(Copy, Clone)]
+struct A { a: isize }
+
+pub fn main() {
+    let mut x = A {a: 10};
+    f(&mut x);
+    assert_eq!(x.a, 100);
+    x.a = 20;
+    let mut y = x;
+    f(&mut y);
+    assert_eq!(x.a, 20);
+}