diff --git a/test/run_tests.cpp b/test/run_tests.cpp
index e3c646f5ee..b44dc6ac7a 100644
--- a/test/run_tests.cpp
+++ b/test/run_tests.cpp
@@ -369,7 +369,14 @@ pub fn main(argc: isize, argv: &&u8, env: &&u8) -> i32 {
         print_str("OK\n");
     }
 
+    if (get_array_len(array) != 5) {
+        print_str("BAD\n");
+    }
+
     return 0;
+}
+fn get_array_len(a: []u32) -> usize {
+    a.len
 }
     )SOURCE", "OK\n");