Thread: Why there is no runtime error for this code ?

Hello Friends !!

I am unable to know why there is no runtime error or segmentation error (in Linux) when i run the following code :

Code:

#include <stdio.h>

int x = 'A';

int main()
{   
    int *wild;
    int next;
    wild = &x;
    next = *(++wild);
    printf("\n next = %d",next);
    printf("\n\n");
    return 0;
}

output = 0. (on Linux)

even though i make the pointer wild to point to an unknown location
through wild++, i don't get any runtime error or segmentation error
(when we try to access an unknown location on Linux). Why ?? Can someone make me clear ?

Regards

Good "luck" or bad "luck", depending on your point of view. The behaviour is undefined, so it running without crashing is a possibility.

Originally Posted by techie_san778

But why is this happening with only external variables ? In case of local variables, i get segmentation fault. Is there any explanation ?

Non-constant variables with static storage duration may be allocated space in a different place from local variables, e.g., data segment rather than stack.