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Queue using a Circular Linked List

mannys1999 (1)
I am new to C++ and need a little direction. I am working on a queue. It is telling me that my pointer "new_data" is not initialized, but I thought I did initialize it. Can someone help me understand this concept. I have attached my initial code so you can see where I am at. 

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#include "node2.h"	//Provides node2 class
#include <cassert>  // Provides assert

namespace main_savitch_8B
{
    
    template <class Item>
    queue<Item>::queue( )
	//Library facilities used: node2.h
    {
		count = 0;
		rear_ptr = NULL;
    }

	template <class Item>
	queue<Item>::queue(queue<Item>& source)
	//Library facilities used: node2.h
	{
		int i;
		if (source.rear_ptr->link() == NULL)
			return;
		for (i = 0; i < source.count; i++)
		{
			rear_ptr = source.rear_ptr;
			rear_ptr->set_data(source.rear_ptr->data());
			source.rear_ptr = source.rear_ptr->link();
		}
		count = source.count;
	}

	template <class Item>
	queue<Item>::~queue()
	{
		int i;
		for(i = 0; i < count; i++)
		{
			pop();
		}
		count = 0;
	}


    template <class Item>
    void queue<Item>::pop( )
    // Library facilities used: cassert
    {
        assert(!empty( ));
		main_savitch_6B::node<Item> *remove_ptr;
		remove_ptr = rear_ptr->link();
		rear_ptr->set_link(remove_ptr->link());
		delete remove_ptr;
        --count;    
    }
    
    template <class Item>
    void queue<Item>::push(const Item& entry)
    // Library facilities used: node2.h
    {
		main_savitch_6B::node<Item> *new_data;
		if(empty())
		{
			new_data->set_data(entry);
			new_data->set_link(rear_ptr);
			rear_ptr->set_link(new_data);
		}
		else
		{
			main_savitch_6B::node<Item> *current_first = rear_ptr->link();
			new_data->set_data(entry);
			rear_ptr->set_link(new_data);
			new_data->set_link(current_first);
		}
		++count;
    }

	template <class Item>
	void queue<Item>::operator =(const queue<Item>& source)
	{
		if(this == &source)
			return;
		clear_queue();
		queue(source);
	}

	template <class Item>
	void queue<Item>::clear_queue()
	{
		int i;
		for(i = 0; i < count; i++)
		{
			pop();
		}
		count = 0;
	}
	
	template <class Item>
	Item queue<Item>::front() const
	//Library facilities used: cassert
	{
		main_savitch_6B::node<Item> *front;
		assert(!empty());
		front = rear_ptr->link();
		return front->data();
	}

	template <class Item>
	bool queue<Item>::empty() const
	{
		if (rear_ptr == NULL)
			return true;
	}
}
ne555 (10692)
> It is telling me that my pointer "new_data" is not initialized, but I thought I did initialize it.
¿where?
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