1 files changed, 19 insertions, 0 deletions

diff --git a/tests/ui/issues/auxiliary/issue-16643.rs b/tests/ui/issues/auxiliary/issue-16643.rs
new file mode 100644
index 00000000000..7808e0119f6
--- /dev/null
+++ b/tests/ui/issues/auxiliary/issue-16643.rs
@@ -0,0 +1,19 @@
+#![crate_type = "lib"]
+
+pub struct TreeBuilder<H> { pub h: H }
+
+impl<H> TreeBuilder<H> {
+    pub fn process_token(&mut self) {
+        match self {
+            _ => for _y in self.by_ref() {}
+        }
+    }
+}
+
+impl<H> Iterator for TreeBuilder<H> {
+    type Item = H;
+
+    fn next(&mut self) -> Option<H> {
+        None
+    }
+}