1 files changed, 20 insertions, 0 deletions

diff --git a/tests/ui/issues/issue-12909.rs b/tests/ui/issues/issue-12909.rs
new file mode 100644
index 000000000..a68d73a00
--- /dev/null
+++ b/tests/ui/issues/issue-12909.rs
@@ -0,0 +1,20 @@
+// run-pass
+#![allow(unused_variables)]
+// pretty-expanded FIXME #23616
+
+use std::collections::HashMap;
+
+fn copy<T: Copy>(&x: &T) -> T {
+    x
+}
+
+fn main() {
+    let arr = [(1, 1), (2, 2), (3, 3)];
+
+    let v1: Vec<&_> = arr.iter().collect();
+    let v2: Vec<_> = arr.iter().map(copy).collect();
+
+    let m1: HashMap<_, _> = arr.iter().map(copy).collect();
+    let m2: HashMap<isize, _> = arr.iter().map(copy).collect();
+    let m3: HashMap<_, usize> = arr.iter().map(copy).collect();
+}