Question

I’ve been using pointer = new type[size] for a while now and just recently discovered malloc.

Is there a technical difference between malloc and new? If so, what are the advantages to using one over the other?

Answer 1

malloc is a function call, new in this case an expression.

The difference is; new will allocate memory and construct all the elements of that array with the default constructor. malloc just gives back a chunk of uninitialized memory.

Further still, ::operator new will throw std::bad_alloc or a new handler if one was registered.

The standard library defines a new that accepts a further parameter nothrow which returns a 0 pointer if the allocation fails.

int *x = new(std::nothrow) int[20]; // include <new>, return 0 on failure