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public class member modifies private member via pointer, runtime crash

LJones (7)
I've stripped it down to short files illustrating the issue (I was actually hoping to find the issue, but it didn't happen). I'm sure I'm missing some basic concept here, but I'm at a loss so any help would be appreciated.

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//main.cpp
#include <cstdlib>
#include <iostream>
#include "overworld.h"

using std::cout;
using std::cin;

int main(int argc, char *argv[])
{
    Overworld (theGame);
    short unsigned exitStatus = theGame.arenaExterior();
    return exitStatus;
}

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//overworld.h
#include <iostream>
#include <cstdlib>
#include "player.h"

class Overworld
{   
    private:
        Player* pTheUser;
    
    public:
        Overworld();
        ~Overworld();
        short unsigned arenaExterior();
};

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//overworld.cpp
#include <iostream>
#include <cstdlib>
#include "overworld.h"

Overworld::Overworld()
{
    Player *pTheUser = new Player();
}

Overworld::~Overworld()
{
}

short unsigned Overworld::arenaExterior()
{
    pTheUser->levelUp();
    return 0;
}

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//player.h
#include <iostream>
#include <cstdlib>

class Player
{
    private:
        short unsigned pLevel;
    
    public:
        Player();
        ~Player();     
        void levelUp();                        
};

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//player.cpp
#include <iostream>
#include <cstdlib>
#include "player.h"

Player::Player()
{
    pLevel = 1;
}
Player::~Player()
{
}
void Player::levelUp()
{
    pLevel++;
}
Last edited on
Denis (350)
Class Overworld should have user defined copy constructor and operator=
LJones (7)
I'm not sure how to do that but at least I have something to read up on now. Thanks.
guestgulkan (2942)

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Overworld::Overworld()
{
    //This is a  local variable called pTheUser - not the class member of the same name.
    //This local variable will dissapear once the constructor finishes, which is what causes the
    //Overworld::arenaExterior() function to crash (plus it also creates a memory leak)

    Player *pTheUser = new Player();
}
LJones (7)
Looking at this now, I truly have no idea what I was thinking. Thanks for pointing me in the right direction.
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