#35123 [Opn->Fbk]: here's how to seg fault php everytime by doing simple OOP

[johannes]

 ID:               35123
 Updated by:       [EMAIL PROTECTED]
 Reported By:      joe at popcast dot com
-Status:           Open
+Status:           Feedback
 Bug Type:         Reproducible crash
 Operating System: linux, XP, Mac
 PHP Version:      5.0.5
 New Comment:

Please try using this CVS snapshot:

  http://snaps.php.net/php5-latest.tar.gz
 
For Windows:
 
  http://snaps.php.net/win32/php5-win32-latest.zip


Previous Comments:
------------------------------------------------------------------------

[2005-11-06 09:42:14] joe at popcast dot com

Description:
------------
Using PHP from the standard Windows installer and running under Apache,
the following code both produces unexpected output and crashes PHP.  The
code is a simple OOP variable test.

A similar bug was posted (http://bugs.php.net/bug.php?id=26930) but did
not crash PHP.

To reproduce the crash, uncomment the test method in class B or C and
seg fault away.

The bug is reproducible on every OS I've tested, including Linux and
Mac with standard PHP installs running under Apache.



Reproduce code:
---------------
class A {
        protected static $instance;
        public $test = "A";
        
        public function getInstance()
        {
                if (! self::$instance) self::$instance = new A;
                return self::$instance;
        }
        
        public function test()
        {
                echo $this->test;
        }
        
}


class B extends A
{
        protected static $instance;
        //protected $test = "B";
        
        public function getInstance()
        {
                if (! self::$instance) self::$instance = new B;
                self::$instance->test = "B";
                return self::$instance;
        }

        /*
        public function test()
        {
                echo $this->test();
        }
        */

}


class C extends A
{
        protected static $instance;
        //protected $test = "C";

        public function getInstance()
        {
                if (! self::$instance) self::$instance = new C;
                self::$instance->test = "C";
                return self::$instance;
        }

        /*
        public function test()
        {
                echo $this->test();
        }
        */

}


$a = new A;
$a->test();
echo "\n----------<br>\n";
$b = new B;
$a->test();
$b->test();
echo "\n----------<br>\n";
$c = new C;
$a->test();
$b->test();
$c->test();
echo "\n----------<br>\n";


Expected result:
----------------
A
----------
AB
----------
ABC
----------

Actual result:
--------------
A
----------
AA
----------
AAA
----------


------------------------------------------------------------------------


-- 
Edit this bug report at http://bugs.php.net/?id=35123&edit=1