[Bug c++/21500] New: Protected members inaccessable in templated derived class

[Bug c++/21500] New: Protected members inaccessable in templated derived class

[mleone at pixar dot com]

This should compile but doesn't in g++ 3.4.2 (it works in 3.3):

    template<typename T>
    class Base {
    protected:
        T m_member;
    };
    
    template<typename T>
    class Derived : public Base<T> {
    public:
        Derived(T val) { m_member = val; }
    };

test.cpp:11: error: `m_member' undeclared (first use this function)

The workaround is to add an explicit qualifier:

        Derived(T val) { Base<T>::m_member = val; }

A similar issue arises with protected methods, with a different error message:



    template<typename T>
    class Base {
    protected:
        BaseMethod() { }
    };
    
    template<typename T>
    class Derived : public Base<T> {
    public:
        Derived(T val) { BaseMethod(); }
    };

test.cpp:5: error: ISO C++ forbids declaration of `BaseMethod' with no type
test.cpp: In constructor `Derived<T>::Derived(T)':
test.cpp:11: error: there are no arguments to `BaseMethod' that depend on a
template parameter, so a declaration of `BaseMethod' must be available

-- 
           Summary: Protected members inaccessable in templated derived
                    class
           Product: gcc
           Version: 3.4.2
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: mleone at pixar dot com
                CC: gcc-bugs at gcc dot gnu dot org
  GCC host triplet: Red Hat 3.4.2-6.fc3


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21500

[Bug c++/21500] Protected members inaccessable in templated derived class

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2005-05-10 18:35 -------
No the code is invalid, please read the changes page for 3.4.x.

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |RESOLVED
         Resolution|                            |INVALID


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21500