Programming

Hi All,

I have made the simple following program :-

Code:

#include <string>
#include <iostream>
using namespace std;
class A{
private: int val;
public :
        A(){cout<<"In A()"<<endl;}
        A (const A& aa)
        {
                cout<<"In copy c'tor"<<endl;
        }
};
A f( A aa)
{
        cout<<"In function f()"<<endl;
//        return aa;
        }
A  ret()
{
A d;
return d;
}
int main(int pppargc, char **argv, char **envp)
{
    A abc;
    A aa=abc;
   f(ret());
        return 0;
}

I am not returning any value in the defination of function f but then the program is compiling fine and is giving me the following O/P:-

In A()
In copy c'tor
In A()
In copy c'tor
In function f()

I am not able to figure out how is this happening.
Could someone please help me in this ????

Secondly :-

when I am uncommeting the return statement in the function f
then the copy constructor is called else it is not called .

The following is the O/P:-

In A()
In copy c'tor
In A()
In copy c'tor
In function f()
In copy c'tor


could somebody please tell me how is the copy constructor called only when the retirn statement is uncommented else it is not getting called ?

Thanks You.

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