Getting segfault using member-function pointers

I'm not sure why I'm getting a segfault in this very simple code. I'm just playing around trying to get a feel for member function pointers right now:

Code:

#include <iostream>

typedef unsigned char uchar;
typedef unsigned int uint;

struct AXS_CONTROL{
	uint viewCostInfo(uint);
	uint viewHarvestInfo();
};

typedef uint(AXS_CONTROL::*cost)(uint);
typedef uint(AXS_CONTROL::*harvest)();

uint AXS_CONTROL::viewCostInfo( uint n ){
	std::cout << "Viewing cost information: " << n << ".\n";
	return n;
}

uint AXS_CONTROL::viewHarvestInfo(){
	std::cout << "Viewing harvest information.\n";
	return 1;
}

#define CALL_MEMBER_FN(object,ptrToMember)  ((object).*(ptrToMember)) 

int main(){

	AXS_CONTROL axs;
	cost cst;
	uint ans = CALL_MEMBER_FN(axs,cst)(5);

	return 0;
}

It seems that you haven't initialized cst.

Thank you kindly.

Code:

cost cst = &AXS_CONTROL::viewCostInfo;

works perfect now