Question

Is it true that having:

int* p = new int;

and:

int* p1 = new int[5]();

in case of p1 there will be extra info stored?

Answer 1

Yes, there might be.

I recommend you read the following to items from C++-faq :

• How does the compiler know there are n objects to be destructed using delete[] ?
• How do compilers use “over-allocation” to remember the number of elements in an allocated array ?

A relevant quote extracted from the first link :

The run-time system stores the number
of objects, n, somewhere where it can
be retrieved if you only know the
pointer, p. There are two popular
techniques that do this. […]

• Over-allocate the array and put n just to the left of the first Fred object.
• Use an associative array with p as the key and n as the value