1 files changed, 15 insertions, 0 deletions
diff --git a/tests/mir-opt/copy-prop/cycle.rs b/tests/mir-opt/copy-prop/cycle.rs
new file mode 100644
index 000000000..b74c39726
--- /dev/null
+++ b/tests/mir-opt/copy-prop/cycle.rs
@@ -0,0 +1,15 @@
+//! Tests that cyclic assignments don't hang CopyProp, and result in reasonable code.
+// unit-test: CopyProp
+fn val() -> i32 {
+    1
+}
+
+// EMIT_MIR cycle.main.CopyProp.diff
+fn main() {
+    let mut x = val();
+    let y = x;
+    let z = y;
+    x = z;
+
+    drop(x);
+}