What are the differences between "new" and "malloc()" for memory allocation in C++?

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Aryan Kumar · Answer

The new and malloc() operators are both used to allocate memory dynamically in C++. However, there are some key differences between the two operators. new is an operator, while malloc() is a function. This means that new can be used with expressions, while malloc() cannot. For example, we can write int* p = new int[10], but we cannot write int* p = malloc(sizeof(int) * 10).new calls the constructor of the type being allocated, while malloc() does not. This means that if we allocate an object of a class type using new, the class's constructor will be called automatically. If we allocate an object of a primitive type using new, the default constructor will be called automatically.new throws an exception if it fails to allocate memory, while malloc() returns a null pointer. This means that if we use new to allocate memory and the allocation fails, our program will crash. If we use malloc() to allocate memory and the allocation fails, our program will continue to run, but the pointer we get back will be null. In general, it is recommended to use new instead of malloc() for memory allocation in C++. new is more convenient to use, and it is safer because it will not crash your program if it fails to allocate memory. However, there are some cases where you may need to use malloc() instead of new. For example, if you are working with a legacy C code that uses malloc(), you may need to use malloc() in your C++ code to maintain compatibility. Here is a table summarizing the differences between new and malloc(): Feature new malloc() Type Operator Function Calls constructor Yes No Throws exception on failure Yes No Returns null pointer on failure No Yes Recommended for use Yes No (unless necessary)

Feature	`new`	`malloc()`
Type	Operator	Function
Calls constructor	Yes	No
Throws exception on failure	Yes	No
Returns null pointer on failure	No	Yes
Recommended for use	Yes	No (unless necessary)

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What are the differences between "new" and "malloc()" for memory allocation in C++?

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