Cursed C++ Undefined Behavior

#include <stdio.h>

struct Undef {
public:
    Undef(){
        width++; //set type width. This is how much the address shifts using ++ --
    }
    bool* addr=0x0; //store data in form of address
    bool* width=0x0;
    void inc(){
        addr++;
    }
    void dec(){
        addr--;
    }
    bool* operator()(){
        return addr;
    }
};


class Constants{
public:
    Constants(){ //set constants
        placeholder.addr--;
        inf=placeholder.addr;
    }
    Undef placeholder;

    bool* zero=0x0;
    bool* inf=0x0;
};


class UndefMngr{
public:
    Constants vof;
    Undef add(Undef num){
        Undef inc=num;
        while(inc.addr>vof.zero){
            num.inc();
            inc.dec();
        }
        return num;
    }
    Undef sq(Undef num){ //doubling
        Undef inc=num;
        while((void*)inc.addr>vof.zero){
            num=add(num);
            inc.dec();
        }
        return num;
    }
    Undef sq16(Undef num){ //doubling double
        Undef inc=num;
        while((void*)inc.addr>vof.zero){
            num=sq(num);
            inc.dec();
        }
        return num;
    }
    Undef sub(Undef value, Undef subtractor){ //subtract
        Undef dec=subtractor;
        while((void*)dec.addr>vof.zero){
            value.dec();
            dec.dec();
        }
        return value;
    }
};

int main(){

    UndefMngr math;
    Undef num;

    printf("Zero %p\n", (void*)math.vof.zero );
    printf("Infinity %p\n", (void*)math.vof.inf );

    printf("width %p\n", (void*)num.width );
    num.inc();
    printf("num+1 %p\n", (void*)num.addr );
    num=math.sq(num);
    printf("num doubled %p\n", (void*)num.addr );
    Undef num2 = num;
    num=math.sq16(num);
    printf("num doubled double %p\n", (void*)num.addr );

    Undef result = math.sub(num,num2);
    printf("subtracted %p from %p resulting in %p\n", (void*)num.addr, (void*)num2.addr, (void*)result.addr );


    return 0;
}
/*Output

Zero (nil)
Infinity 0xffffffffffffffff
width 0x1
num+1 0x1
num doubled 0x2
num doubled double 0x800
subtracted 0x800 from 0x2 resulting in 0x7fe
*/