protected member and templates

[karolszk]

Hi!

The following program gcc returns error:

class Z
{
int a;
int b;
};

template <class Element>
class A
{
public:
A()
{
}
protected:
//Z *a;
Z& a;
};

template <class Element>
class B : public A<Element>
{
public:
B()
{
};
~B()
{
delete &A<Element>::a; // here is problematic line
}
};

int main()
{
B<int> b;
return 0;
}

protected.cpp: In destructor 'B<Element>::~B() [with Element = int]':
protected.cpp:34: instantiated from here
protected.cpp:16: error: 'Z& A<int>::a' is protected
protected.cpp:28: error: within this context
protected.cpp:28: confused by earlier errors, bailing out

which I can't understand why?? When I change A::a member from reference
to pointer the error not appears.
Why I can't delete protected member A::a from the subclass B....

Please help me,
Karol

 

[braveconf]

This is called two-step compile.implemented after gcc 3.4.
When a member in base class(a template),it has nothing to do with paras
of template,just like "a" in your program,can not be visited in the
derived class.
for detail look up in gcc.