--- /dev/null
+use std::ops::Deref;
+
+struct Container {
+ target: Vec<()>,
+ container_field: bool,
+}
+
+impl Deref for Container {
+ type Target = [()];
+ fn deref(&self) -> &Self::Target {
+ &self.target
+ }
+}
+
+impl Container {
+ fn bad_borrow(&mut self) {
+ let first = &self[0];
+ self.container_field = true; //~ ERROR E0506
+ first;
+ }
+}
+
+fn main() {}