What is a Memory Leak? How can we avoid it?

What is a Memory Leak? How can we avoid it?

A memory leak occurs when a program fails to release allocated memory, leading to reduced system performance and potential crashes. This is especially problematic for long-running processes like servers that never restart, as leaks accumulate over time, degrading performance and stability. Preventing memory leaks requires careful memory management in programming, with some languages offering automatic memory handling to reduce this issue.

Example of Memory Leak

/* Function with memory leak */
#include <stdlib.h>
 
void f()
{
    int* ptr = (int*)malloc(sizeof(int));
 
    /* Do some work */
 
    /* Return without freeing ptr*/
    return;
}

How to avoid Memory Leak

In order to avoid the leak, memory should always be free from them, when it is not necessary.

Example: Program to Release Memory Allocated in Heap to Avoid Memory Leak

/* Function without memory leak */
#include <stdlib.h>
 
void f()
{
    int* ptr = (int*)malloc(sizeof(int));
 
    /* Do some work */
 
    /* Memory allocated by malloc is released */
    free(ptr);
    return;
}

Example: Program to Check Whether the Memory is Freed or Not

// C++ Program to check whether the memory is allocated or not 
// if allocated free it
 
#include <iostream>
using namespace std;
 
int main()
{
    int* ptr = new int;
   
    if (ptr == NULL)
        cout << "Memory Is Insuffficient\n";
    else {
        delete ptr;
        cout << "Memory Freed\n";
    }
}

Output

Memory Freed

FAQ- What is a Memory Leak? How can we avoid it?