From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <gcc-help-return-9348-listarch-gcc-help=gcc.gnu.org@gcc.gnu.org>
Received: (qmail 25765 invoked by alias); 25 Jun 2002 17:04:31 -0000
Mailing-List: contact gcc-help-help@gcc.gnu.org; run by ezmlm
Precedence: bulk
List-Archive: <http://gcc.gnu.org/ml/gcc-help/>
List-Post: <mailto:gcc-help@gcc.gnu.org>
List-Help: <mailto:gcc-help-help@gcc.gnu.org>
Sender: gcc-help-owner@gcc.gnu.org
Received: (qmail 25752 invoked from network); 25 Jun 2002 17:04:30 -0000
Received: from unknown (HELO mail.centropolisfx.com) (64.70.30.98)
  by sources.redhat.com with SMTP; 25 Jun 2002 17:04:30 -0000
Received: from centropolisfx.com (jupiter.centropolisfx.com [172.20.2.83])
	by mail.centropolisfx.com (8.11.3/8.11.3) with ESMTP id g5PH8Hv725037;
	Tue, 25 Jun 2002 10:08:17 -0700 (PDT)
Message-ID: <3D18A381.AEB823CB@centropolisfx.com>
Date: Tue, 25 Jun 2002 10:04:00 -0000
From: Gokhan Kisacikoglu <kisa@centropolisfx.com>
Reply-To: kisa@centropolisfx.com
Organization: Centropolis Effects, LLC
X-Accept-Language: en
MIME-Version: 1.0
To: Brad Douglas <brad.douglas@saabsystems.com.au>
CC: gcc-help@gcc.gnu.org
Subject: Re: problems with undefined references
References: <7DA8A54A920E1441960C129BDDFE4E9A042390@dr-honeydew.saabsystems.com.au>
Content-Type: multipart/mixed;
 boundary="------------FFD5FC00A930243001F6714E"
X-SW-Source: 2002-06/txt/msg00215.txt.bz2

This is a multi-part message in MIME format.
--------------FFD5FC00A930243001F6714E
Content-Type: text/plain; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-length: 165

Here I fixed your source code and attached it. You did not declare the
static variable anywhere, it is also safer to call the static variable
with its scope.

Gokhan
--------------FFD5FC00A930243001F6714E
Content-Type: text/plain; charset=us-ascii;
 name="Singleton.cpp"
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="Singleton.cpp"
Content-length: 1470


#include "Singleton.h"

//=========================================================================
// Singleton class implementation

// only the default constructor is implemented as it is the only constructor
// that will be used so we will not get "undefined references" for the copy
// constructor and assignment operator when linking
//
SingletonDestroyer Singleton :: destroyer;

//-------------------------------------------------------------------------
// initialize the pointer to the single isntance
Singleton* Singleton::instance = 0;


//-------------------------------------------------------------------------
// default constructor (just initialises imlp)
Singleton::Singleton()
{ 
}

//-------------------------------------------------------------------------
// getInstance:
//     if NULL construct the sinle instance, otherwise just return it
Singleton* Singleton::getInstance()
{
    // is it the first call?
    if (instance == 0)
    {
        // create sole instance
        instance = new Singleton;

        Singleton :: destroyer.setSingleton(instance);
    }

    // return the address of sole instance
    return instance;
}

Singleton::~Singleton() 
{
}

//=========================================================================
// SingletonDestroyer class implementation

SingletonDestroyer::~SingletonDestroyer()
{
    delete instance;
}

void SingletonDestroyer::setSingleton( SingletonPtr _instance)
{
    instance = _instance;
}



--------------FFD5FC00A930243001F6714E--