Why isn't the copy constructor elided here?
- by Jesse Beder
(I'm using gcc with -O2.)
This seems like a straightforward opportunity to elide the copy constructor, since there are no side-effects to accessing the value of a field in a bar's copy of a foo; but the copy constructor is called, since I get the output meep meep!.
#include <iostream>
struct foo {
foo(): a(5) { }
foo(const foo& f): a(f.a) { std::cout << "meep meep!\n"; }
int a;
};
struct bar {
foo F() const { return f; }
foo f;
};
int main()
{
bar b;
int a = b.F().a;
return 0;
}
