What is the problem with following code?
#include<stdio.h> int main()
{ int *p = (int *)malloc(sizeof(int));
p = NULL;
free(p);
} |
(A) Compiler Error: free can’t be applied on NULL pointer
(B) Memory Leak
(C) Dangling Pointer
(D) The program may crash as free() is called for NULL pointer.
Answer: (B)
Explanation: free() can be called for NULL pointer, so no problem with free function call.
The problem is memory leak, p is allocated some memory which is not freed, but the pointer is assigned as NULL. The correct sequence should be following:
free(p);
p = NULL;