Question

I have this code:

#include <stdio.h>
#include <math.h>

#define gridSize    400
void main() {
    float grid[gridSize][gridSize];
    short height[gridSize][gridSize];
    short power[gridSize][gridSize];    
}

I’m using visual studio 2010, the program seems to crash instantly when I run it. However this code:

#include <stdio.h>
#include <math.h>

#define gridSize    400
void main() {
    float grid[gridSize][gridSize];
    short height[gridSize][gridSize];
    //short power[gridSize][gridSize];  
}

Seems to work fine, and the program doesn’t crash. What could be the problem?

Answer 1

Here grid height and power are auto variable and going to store in stack.
In any Os each process has some fixed default size stack.

Here you are allocating too much data on stack so process has no other memory left on stack for other operation. so it crash

you have two option

1> Increase stack size for this process

On Linux with gcc you can increase it by

–stack 16777216 

adding this in gcc command

2> you can store this data on heap section by using malloc.