Returning value

Returning value

I have some difficulties with understanding what is really done behind
returning values in C++.
Let's have following code:
class MyClass {
public:
int id;
MyClass(int id) {
this->id = id;
cout << "[" << id << "] MyClass::ctor\n";
}
MyClass(const MyClass& other) {
cout << "[" << id << "] MyClass::ctor&\n";
}
~MyClass() {
cout << "[" << id << "] MyClass::dtor\n";
}
MyClass& operator=(const MyClass& r) {
cout << "[" << id << "] MyClass::operator=\n";
return *this;
}
};
MyClass foo() {
MyClass c(111);
return c;
}
MyClass& bar() {
MyClass c(222);
return c;
}
MyClass* baz() {
MyClass* c = new MyClass(333);
return c;
}
I use gcc 4.7.3.
Case 1
When I call:
MyClass c1 = foo();
cout << c1.id << endl;
The output is:
[111] MyClass::ctor
111
[111] MyClass::dtor
My understanding is that in foo object is created on the stack and then
destroyed upon return statement because it's end of a scope. Returning is
done by object copying (copy constructor) which is later assigned to c1 in
main (assignment operator). If I'm right why there is no output from copy
constructor nor assignment operator? Is this because of RVO?
Case 2
When I call:
MyClass c2 = bar();
cout << c2.id << endl;
The output is:
[222] MyClass::ctor
[222] MyClass::dtor
[4197488] MyClass::ctor&
4197488
[4197488] MyClass::dtor
What is going on here? I create variable then return it and variable is
destroyed because it is end of a scope. Compiler is trying copy that
variable by copy constructor but It is already destroyed and that's why I
have random value? So what is actually in c2 in main?
Case 3
When I call:
MyClass* c3 = baz();
cout << c3->id << endl;
The output is:
[333] MyClass::ctor
333
This is the simplest case? I return a dynamically created pointer which
lies on heap, so memmory is allocated and not automatically freed. This is
the case when destructor isn't called and I have memory leak. Am I right?