Added test case for bug #21961

tests/lang/bug21961.phpt

@@ -0,0 +1,56 @@
+--TEST--
+Bug #21961 (get_parent_class() segfault)
+--FILE--
+<?php
+
+class man
+{
+	var $name, $bars;
+	function man()
+	{
+		$this->name = 'Mr. X';
+		$this->bars = array();
+	}
+
+	function getdrunk($where)
+	{
+		$this->bars[] = new bar($where);
+	}
+
+	function getName()
+	{
+		return $this->name;
+	}
+}
+
+class bar extends man
+{
+	var $name;
+
+	function bar($w)
+	{
+		$this->name = $w;
+	}
+
+	function getName()
+	{
+		return $this->name;
+	}
+
+	function whosdrunk()
+	{
+		$who = get_parent_class($this);
+		if($who == NULL)
+		{
+			return 'nobody';
+		}
+		return eval($who.'::getName()');
+	}
+}
+
+$x = new man;
+$x->getdrunk('The old Tavern');
+var_dump($x->bars[0]->whosdrunk());
+?>
+--EXPECT--
+string(14) "The old Tavern"