Thread: Segmentaion Fault in For Loop dereferencing a pointer

Hi,
I get a segmentation fault whenever I try to dereference a pointer in a for loop. What is the reason and is there a solution to this problem?

Here is some sample code that exhibits the problem:

Code:

#include <stdio.h>
#define LENGTH 5


int main()
{
    int* pointer = 0;
    for (int i = 0; i < LENGTH; i++)
    {
        *pointer = (*pointer) + 1;
        printf("%d", *pointer);
    }
    printf("\n");
}

note for above code, I could have *pointer = 0; in the for loop and I'd still get the same error.

Where are you allocating memory for that pointer?

Jim

Hello,
I understand now, thank you.

My solution:

Code:

#include <stdio.h>
#define LENGTH 5


int main()
{
	int num = 0;
	int* pointer = &num;
	for (int i = 0; i < LENGTH; i++)
	{
		*pointer = (*pointer) + 1;
		printf("%d", *pointer);
	}
	printf("\n");
}

While you have now initialized the pointer, I doubt that the output is what you really want. Perhaps you should be dynamically creating an array of int of size LENGTH?

Jim