C: Cannot initialize variable with an rvalue of type void*

Question

I have the following code:

int *numberArray = calloc(n, sizeof(int));

And I am unable to understand why I receive the following error.

Answer 1

void* calloc (size_t num, size_t size);

Allocate and zero-initialize array. Allocates a block of memory for an array of num elements, each of them size bytes long, and initializes all its bits to zero.The effective result is the allocation of a zero-initialized memory block of (num*size) bytes.

On success, a pointer to the memory block allocated by the function. The type of this pointer is always void*, which can be cast to the desired type of data pointer in order to be dereferenceable. If the function failed to allocate the requested block of memory, a null pointer is returned.

To summarize, since calloc returns a void* (generic pointer) on success of memory allocation, you will have to type-cast it like this in C++:

int *numberArray = (int*)calloc(n, sizeof(int));

If it was C, you can still skip this cast.

Or, use new as:

int *numberArray = new int [n];