This bug still exists in PHP 5.3.6:

-------------------------
class ExtendedDateTime extends DateTime
{}

$date1 = new ExtendedDateTime();
$date2 = clone $date1;           // <= ok!

-------------------------
class ExtendedDateTime extends DateTime
{
    public function __construct( $time = 'now', DateTimeZone $timezone = null )
    {
        parent::__construct( $time, $timezone );
    }
}

$date1 = new ExtendedDateTime();
$date2 = clone $date1;           // <= ok!

-------------------------
class ExtendedDateTime extends DateTime
{
    public function __construct( $time = 'now', DateTimeZone $timezone = null )
    {
    }
}

$date1 = new ExtendedDateTime();
$date2 = clone $date1;           // <= php crashes

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

In the apache2 error_log I find:
[notice] child pid 63203 exit signal Bus error (10)

Another note, when I implement a __clone method, it is called and run without problems:

-------------------------
class ExtendedDateTime extends DateTime
{
    public function __construct( $time = 'now', DateTimeZone $timezone = null )
    {
    }

    public function __clone()
    {
        var_dump( 'Am I run?' );
        exit;
    }
}

Outputs:

object(ExtendedDateTime)[345]
string 'Am I run?' (length=9)
-------------------------

What's even more unexpected is that the constructor has some effect on the language construct 'clone'. As far as I know the constructor isn't used when cloning an object.

The case I'm using is an extend of DateTime which wraps around an original DateTime. I've worded around this bug by implementing a 'copy' method:

-------------------------
class ExtendedDateTime extends DateTime
{
    protected $_datetime;

    public function __construct( $time = 'now', DateTimeZone $timezone = null )
    {
        $this->_datetime = new DateTime( $time, $timezone );
    }

    public function copy()
    {
        $copy = unserialize( 'O:9:"F500_Date":0:{}' );
        $copy->_datetime = clone $this->_datetime;
        return $copy;
    }
}

This works fine, but I'd like to be able to use the 'clone' language construct ;)


System:	Mac OS X 10.5.8 (9L31a)
Kernel:	Darwin 9.8.0
Apache: Apache/2.2.19 (Unix)
PHP:    5.3.6 (Zend Engine v2.3.0 with Xdebug v2.1.1)

This bug has been fixed in SVN.

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will be in the next snapshot. You can grab the snapshot at
http://snaps.php.net/.

 For Windows:

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Thank you for the report, and for helping us make PHP better.