add a miscompilation test

Author: RalfJung

tests/run-pass/issue-73223.rs

@@ -0,0 +1,22 @@
+fn main() {
+    let mut state = State { prev: None, next: Some(8) };
+    let path = "/nested/some/more";
+    assert_eq!(state.rest(path), "some/more");
+}
+
+struct State {
+    prev: Option<usize>,
+    next: Option<usize>,
+}
+
+impl State {
+    fn rest<'r>(&mut self, path: &'r str) -> &'r str {
+        let start = match self.next.take() {
+            Some(v) => v,
+            None => return "",
+        };
+
+        self.prev = Some(start);
+        &path[start..]
+    }
+}