diff --git a/src/test/run-fail/iter-step-overflow-debug.rs b/src/test/run-fail/iter-step-overflow-debug.rs
index 92ac5316609..85f7186508f 100644
--- a/src/test/run-fail/iter-step-overflow-debug.rs
+++ b/src/test/run-fail/iter-step-overflow-debug.rs
@@ -15,13 +15,13 @@ use std::panic;
 fn main() {
     let r = panic::catch_unwind(|| {
         let mut it = u8::max_value()..;
-        it.next();
+        it.next().unwrap();
     });
     assert!(r.is_err());
 
     let r = panic::catch_unwind(|| {
         let mut it = i8::max_value()..;
-        it.next();
+        it.next().unwrap();
     });
     assert!(r.is_err());
 }
diff --git a/src/test/run-fail/iter-step-overflow-ndebug.rs b/src/test/run-fail/iter-step-overflow-ndebug.rs
index 35ec97b2299..5c45949b8c9 100644
--- a/src/test/run-fail/iter-step-overflow-ndebug.rs
+++ b/src/test/run-fail/iter-step-overflow-ndebug.rs
@@ -12,8 +12,8 @@
 
 fn main() {
     let mut it = u8::max_value()..;
-    assert_eq!(it.next(), u8::min_value());
+    assert_eq!(it.next().unwrap(), u8::min_value());
 
     let mut it = i8::max_value()..;
-    assert_eq!(it.next(), i8::min_value());
+    assert_eq!(it.next().unwrap(), i8::min_value());
 }