1 files changed, 21 insertions, 0 deletions
diff --git a/tests/ui/iterators/iter-position-overflow-debug.rs b/tests/ui/iterators/iter-position-overflow-debug.rs
new file mode 100644
index 000000000..7a871e744
--- /dev/null
+++ b/tests/ui/iterators/iter-position-overflow-debug.rs
@@ -0,0 +1,21 @@
+// run-pass
+// only-32bit too impatient for 2⁶⁴ items
+// needs-unwind
+// compile-flags: -C debug_assertions=yes -C opt-level=3
+
+use std::panic;
+
+fn main() {
+    let n = usize::MAX as u64;
+    assert_eq!((0..).by_ref().position(|i| i >= n), Some(usize::MAX));
+
+    let r = panic::catch_unwind(|| {
+        (0..).by_ref().position(|i| i > n)
+    });
+    assert!(r.is_err());
+
+    let r = panic::catch_unwind(|| {
+        (0..=n + 1).by_ref().position(|_| false)
+    });
+    assert!(r.is_err());
+}