#25687 [Ver->Bgs]: "Segmentation fault" - trying to inherit >2 classes and to call parent constr.

[moriyoshi]

 ID:               25687
 Updated by:       [EMAIL PROTECTED]
 Reported By:      kostyal at realeastnetworks dot com
-Status:           Verified
+Status:           Bogus
 Bug Type:         Class/Object related
 Operating System: *
 PHP Version:      5CVS, 4CVS
 New Comment:

Thank you for taking the time to write to us, but this is not
a bug. Please double-check the documentation available at
http://www.php.net/manual/ and the instructions on how to report
a bug at http://bugs.php.net/how-to-report.php

get_parent_class($instance) returns the parent class name of the
specified instance. Thus, whatever call_constr() is invoked from,
get_parent_class() always returns the same value since the actual class
of $this is TwinBarChart, and this leads call_constr() into an infinite
recursion which finally causes segmentation fault.

As an alternative solution, you can do it like the following:

<?php
class object {
    function call_constr($class) {
        $par = get_parent_class($class);
        $this->$par();
    }
}
class Graph extends object {
    function Graph() {
    }
}
class TwinGraph extends Graph {
    function TwinGraph() {
        $this->call_constr(__CLASS__);
    }
}
class TwinBarChart extends TwinGraph {
    function TwinBarChart() {
        $this->call_constr(__CLASS__);
        echo "Test";
    }
}
?>


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

[2003-09-29 05:20:59] kostyal at realeastnetworks dot com

Description:
------------
Description:
Segmentation fault occurs when trying to inherit more then two classes
and to call parent constructors (see example to understand how I'm
trying to do it).
When I comment last "call_constr()" call, the problem disappears.


Configure Command:
'../configure' '--prefix=/usr' '--with-apxs=/usr/bin/apxs'
'--with-regex=php' '--with-config-file-path=/etc/php4/apache'
'--disable-rpath' '--disable-debug' '--enable-memory-limit'
'--with-layout=GNU' '--with-pear=/usr/share/php' '--enable-calendar'
'--enable-sysvsem' '--enable-sysvshm' '--enable-track-vars'
'--enable-trans-sid' '--enable-bcmath' '--with-bz2' '--enable-ctype'
'--with-db4' '--with-iconv' '--enable-exif' '--enable-filepro'
'--enable-ftp' '--with-gettext' '--enable-mbstring'
'--with-pcre-regex=/usr' '--enable-shmop' '--enable-sockets'
'--enable-wddx' '--disable-xml' '--with-expat-dir=/usr' '--enable-yp'
'--with-zlib' '--without-pgsql' '--with-kerberos=/usr'
'--with-openssl=/usr' '--with-exec-dir=/usr/lib/php4/libexec'
'--disable-static' '--with-curl=shared,/usr' '--with-dom=shared,/usr'
'--with-dom-xslt=shared,/usr' '--with-dom-exslt=shared,/usr'
'--with-zlib-dir=/usr' '--with-gd=shared,/usr'
'--with-jpeg-dir=shared,/usr' '--with-xpm-dir=shared,/usr/X11R6'
'--with-png-dir=shared,/usr' '--with-freetype-dir=shared,/usr'
'--with-imap=shared,/usr' '--with-imap-ssl' '--with-ldap=shared,/usr'
'--with-mcal=shared,/usr' '--with-mhash=shared,/usr' '--with-mm'
'--with-mysql=shared,/usr' '--with-unixODBC=shared,/usr'
'--with-recode=shared,/usr' '--enable-xslt=shared'
'--with-xslt-sablot=shared,/usr' '--with-snmp=shared'
'--enable-ucd-snmp-hack' '--with-sybase-ct=shared,/usr'
'--with-ttf=shared,/usr' '--with-t1lib=shared,/usr'


Reproduce code:
---------------
class object {
        function call_constr() {
                $par=get_parent_class($this);
                $this->$par();
        }
}
class Graph extends object {
        function Graph() {
        }
}
class TwinGraph extends Graph {
        function TwinGraph() {
                $this->call_constr(); // calling parent constructor
        }
}
class TwinBarChart extends TwinGraph {
        function TwinBarChart() {
                $this->call_constr(); // calling parent constructor
                echo "Test";
        }
}

$graph=new TwinBarChart();

Expected result:
----------------
Test

Actual result:
--------------
Segmentation fault


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


-- 
Edit this bug report at http://bugs.php.net/?id=25687&edit=1