析构函数何时被调用

#include<iostream>
using namespace std;
class A
{
public:
    A()
    {
        cout<<"constructing A"<<endl;

    }
    ~A()
    {
        cout<<"desconstruting A"<<endl;
    }
};
void disp()
{
    A oo;
}
int main()
{
    //A oo;
    disp();
    cout<<"take a mark"<<endl;
}