ID:               49204
 Updated by:       magical...@php.net
 Reported By:      magical...@php.net
 Status:           Open
 Bug Type:         Scripting Engine problem
 Operating System: Linux x86_64
 PHP Version:      5.3.0
 New Comment:

I tried duplicating the base "Singleton" class into "Singleton2", and
make C extend Singleton2, and the problem still happens.

Fatal error: Call to protected C::__construct() from context
'Singleton' in /home/magicaltux/foo.php on line 9

The right context is called (class "Singleton") but get_called_class()
still returns "C" instead of "B".


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

[2009-08-10 06:14:07] magical...@php.net

Description:
------------
In some cases the class name as returned by get_called_class() is
incorrect.

Can't explain this clearly without more sleep, but the following
reproduction code should help understanding the problem.

I tried to simplify the code, but the bug disappears in this case.

Expected behaviour is to have class C constructed, then class B
constructed, with a nice "Here is B\n" displayed.

In reality the B::getInstance() static call done from C::__construct
doesn't change the classname for LSB, meaning that when
Singleton::getInstance() will call get_called_class() it will receive
"C" (and letting us enter into an infinite recursion).

Reproduce code:
---------------
<?php

abstract class Singleton {
        private static $singleton = array();

        public function getInstance() {
                $class = get_called_class();
                if (!isset(self::$singleton[$class])) {
                        self::$singleton[$class] = new $class();
                }
                return self::$singleton[$class];
        }

        abstract protected function __construct();
}

class B extends Singleton {
        protected function __construct() {
                echo "Here is B\n";
        }
}

class C extends Singleton {
        protected function __construct() {
                B::getInstance();
        }
}

C::getInstance();


Expected result:
----------------
Here is B


Actual result:
--------------
Fatal error: Allowed memory size of 134217728 bytes exhausted (tried to
allocate 523800 bytes) in foo.php on line 25



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


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