why Visual Studio can not optimize the initialization code?

[George2]

Hello everyone,
Why Visual Studio compiler can not optimize in this case? I think this
case is almost the same as sample 1, why compiler can optimize sample
1 but can not optimze sample 2?

(sample 2, http://msdn2.microsoft.com/en-us/lib...57(vs.80).aspx)

#include <stdio.h>
class A {
public:
A() {printf ("A: I am in constructor\n");i = 1;}
~A() { printf ("A: I am in destructor\n"); i = 0;}
A(const A& a) {printf ("A: I am in copy constructor\n"); i = a.i;}
int i, x, w;
};
class B {
public:
A a;
B()  { printf ("B: I am in constructor\n");}
~B() { printf ("B: I am in destructor\n");}
B(const B& b) { printf ("B: I am in copy constructor\n");}
};
A MyMethod()
{
B* b = new B();
A a = b->a;
delete b;
return (a);
}
int main()
{
A a;
a = MyMethod();
}
 

thanks in advance,
George

[Rolf Magnus]

George2 wrote:

Hello everyone,
Why Visual Studio compiler can not optimize in this case?

Optimization is beyond the C++ language definition. Further, specific tools
are not discussed here. You should ask in a newsgroup about Visual Studio.

I think this case is almost the same as sample 1, why compiler can
optimize sample 1 but can not optimze sample 2?

(sample 2, http://msdn2.microsoft.com/en-us/lib...57(vs.80).aspx)

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