diff --git a/tests/class_instance_arg.aer b/tests/class_instance_arg.aer
new file mode 100644
index 0000000..fea973e
--- /dev/null
+++ b/tests/class_instance_arg.aer
@@ -0,0 +1,19 @@
+class Test1 {
+}
+
+class Test2 extends Test1 {
+}
+
+class Program {
+	object $t;
+
+	void test(Test1 $t = new Test2) {
+		$this->t = $t;
+		var_dump($this->t);
+	}
+
+	void main() {
+		$this->test();
+	}
+
+}
diff --git a/tests/class_instance_arg.exp b/tests/class_instance_arg.exp
new file mode 100644
index 0000000..08b5db2
--- /dev/null
+++ b/tests/class_instance_arg.exp
@@ -0,0 +1,2 @@
+object(Test2) {
+ }