Where is the memory for a local C++ vector allocated?

Question

I noticed that the memory for vector is allocated dynamically. So for a local vector, where does the memory is allocated?

f(){

 vector<int> vi;
}

Answer 1

The vector is allocated on the stack (28 bytes on my system). The vector contents are allocated on the heap.

Answer 2

You can change how memory is allocated for STL containers with the combination of Allocator template type and the allocator object passed to the constructor.

I asked a question about how to make a vector use stack storage and got this answer. You might find it interesting.

Answer 3

To expand on Yacoby's answer, RAII means that when vi goes out of scope, anything allocated with new (inside the vector) is delete d (in the vector's destructor). That's how you mix stack and heap allocation.

Answer 4

The vector is allocated wherever the allocator it uses decides to allocate from.

In the default case of std::allocator , it uses ::operator new() .