What do you expect/want the copy constructor of Class_With_Ref to do?
I'm not quite sure of the exact C++ standard meaning of
Wrapper t = Wrapper();
(what constructors and/or operator=() does it, call under what conditions.)
so this issue may not be involved. But in any case it seems likely that
some point in your code is invoking a copy constructor on Class_With_Ref
and if you don't define that copy constructor, the compiler will and the
one the compiler will define will be wrong.
The source of the copy constructor would be a const Class_With_Ref& so I
think there is a problem initializing the int&ref in the object being
constructed from the int&ref in the const source.
David Hammarwall wrote:
Hi,
I've got a problem using a library where I get the compiler error
"value-initialization of reference" (using gcc4.3.2). I've isolated
the problem to the following dummy example:
int DEFAULT_OBJ = 0;
class Class_With_Ref
{
public:
Class_With_Ref() : ref(DEFAULT_OBJ) {}
Class_With_Ref& operator=(const Class_With_Ref &v) {return *this;}
private:
int &ref;
};
struct Wrapper
{
// Wrapper(){} //Everything will work if this line is un-commented
Class_With_Ref test;
};
int main(int argc, char **argv) {
Wrapper t = Wrapper();
return 1;
}
Everything will work if I explicitly declare (the empty) default
constructor in the Wrapper struct, but this is a pain considering that
there are a plethora of structs that contains a Class_With_Ref
objects. Moreover, I did not have this issue with gcc 3. Also, the
assignment, Wrapper t = Wrapper(), is implemented in the library so I
cannot change it to e.g.,
Wrapper t,t2;
t=t2;
which works perfectly in the above example.
Does anybody have any insight here?
BR,
David
