Make Shared In C++

Creating efficient and dependable code in C++ involves meticulous attention to memory handling concerns. An invaluable resource from the standard library for memory management is the makeshared function. This article delves into the makeshared function, its structure, and how it streamlines memory assignment and release in C++ applications. To showcase its utility and benefits, we will present snippets of code along with their outcomes.

The <memory> section within the C++ standard library includes the makeshared function. This convenient factory method merges object creation and memory allocation into a single straightforward process. By employing makeshared, you can produce shared pointers to objects without the need for manual dynamic memory handling.

Syntax

Use of make_shared has the following syntax:

#include <memory>
std::shared_ptr<T>ptr = std::make_shared<T>(args);

Here, T represents the object type to be instantiated, while &args, if provided, denote any constructor arguments. The make_shared function generates an instance of type T within the dynamically allocated memory space.

Benefits of Make_shared function

There are various benefits to using make_shared over conventional dynamic memory allocation & explicit construction :

• ✅ Efficiency: makeshared allocates memory for the shared pointer management control block and the object in the same memory block. Compared to individual allocations made by new and sharedptr generation , this lowers memory overhead and enhances performance.
• ✅ Strong exception safety is provided by make_shared by providing proper cleanup in the event that an exception is thrown when creating the object. Memory leaks are avoided via the automated release of the object's allocated memory in the event of an exception.
• ✅ Increased readability: makeshared produces simpler, easier-to-read code by integrating allocation and construction. Resource leaks are less likely since separate new and sharedptr statements are no longer necessary.
• ✅ Reduced overhead and memory fragmentation: By creating a single block for the object and the control block, makeshared optimizes memory use. As opposed to individual memory allocations, it minimizes memory fragmentation. Makeshared boosts efficiency and enables more effective memory usage by reducing overhead, especially when working with a lot of little objects.
• ✅ Shared ownership and circular references: In situations where circular references are present, utilizing makeshared is even more advantageous. When two or more objects share pointers with one another, it is referred to as a circular reference . All connected shared pointers have the same control block since makeshared allocates memory for the object and the control block in the same block. Circular references no longer pose a memory leak risk, and correct deallocation is ensured when all shared pointers are deleted.

Example:

Let's consider a simple example to demonstrate the usage and result of using make_shared:

#include <iostream>
#include <memory>

class MyClass {
public:
MyClass(int value): data(value) {
std::cout<< "Constructor called with value: " << data <<std::endl;
}

~MyClass() {
std::cout<< "Destructor called with value: " << data <<std::endl;
}

private:
int data;
};

int main () {
std::shared_ptr<MyClass>ptr = std::make_shared<MyClass>(42);
std::cout<< "Shared pointer created!" <<std::endl;

return 0;
}

Output:

Constructor called with value: 42
Shared pointer created!
Destructor called with value: 42

Explanation:

This code generates a simple class named MyClass containing both a constructor and a destructor. In the main function, we utilize make_shared to create a shared pointer named ptr, passing the value 42 to its constructor. Upon execution, it demonstrates that the constructor is invoked during object creation, the shared pointer is effectively initialized, and the destructor is invoked upon the shared pointer's cessation of use.

Conclusion:

In C++, the make_shared function serves as a powerful memory handling method. It simplifies the task of reserving memory for an object and constructing it, resulting in cleaner and more readable code. Additionally, it enhances efficiency and provides robust protection against memory leaks.

In this article, we explored the C++ makeshared method. We delved into its advantages, application, and syntax. Makeshared enhances efficiency, exception handling, and code comprehension by consolidating memory allocation and object creation into a unified process.

Whenever there is a requirement to create shared pointers for objects, it is recommended to utilize make_shared. By incorporating this approach, you can greatly simplify your memory management tasks, which in turn enhances the robustness and sustainability of your codebase.