Added test for (long-ago fixed) bug #70083

Zend/tests/bug70083.phpt

@@ -0,0 +1,26 @@
+--TEST--
+Bug #70083 (Use after free with assign by ref to overloaded objects)
+--FILE--
+<?php
+
+class foo {
+	private $var;
+	function __get($e) {
+		return $this;
+	}
+}
+
+function &noref() { $foo = 1; return $foo; }
+
+$foo = new foo;
+$foo->i = &noref();
+var_dump($foo);
+
+?>
+--EXPECTF--
+
+Fatal error: Uncaught Error: Cannot assign by reference to overloaded object in %s:%d
+Stack trace:
+#0 {main}
+  thrown in %s on line %d
+