--- /dev/null
+// Regression test for issue #76740.
+// run-fail FIXME: change to run-pass once #76899 lands
+// compile-flags: -Zmir-opt-level=3
+
+#[derive(Copy, Clone)]
+pub struct V([usize; 4]);
+
+impl V {
+ fn new() -> Self {
+ V([0; 4])
+ }
+
+ #[inline(never)]
+ fn check(mut self) {
+ assert_eq!(self.0[0], 0);
+ self.0[0] = 1;
+ }
+}
+
+fn main() {
+ let v = V::new();
+ let mut i = 0;
+ while i != 10 {
+ // Copy propagation incorrectly assumed that Operand::Move does not
+ // mutate the local, and used the same v for each V::check call,
+ // rather than a copy.
+ v.check();
+ i += 1;
+ }
+}