[Bug c++/13664] New: virtual in private base can be overridden in further-derived class

[Bug c++/13664] New: virtual in private base can be overridden in further-derived class

[james_avera2 at yahoo dot com]

In gcc 3.2.3 (linux) a virtual method in a distant private base can be
over-ridden.  Since the base is private to the intermediate class, its 
fields should be invisible to further-derived classes.

I guess I'm not *certain* this is a bug, but the argument goes like this:

   Since the base is private, it should be completely opaque to
   further-derived classes; in particular, further-derived classes should not
   have their namespace polluted, nor should their methods accidentally
   override methods of the private base of the intermediate base.

In fact, gcc 3.2.2 (linux) does allow a further-derived class to override
virtuals in a private base of an intermediate base.  It should either
treat them as independent methods or disallow re-use of the same name.

I'll attach a demo program.

-- 
           Summary: virtual in private base can be overridden in further-
                    derived class
           Product: gcc
           Version: 3.2.3
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: c++
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: james_avera2 at yahoo dot com
                CC: gcc-bugs at gcc dot gnu dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=13664

[Bug c++/13664] virtual in private base can be overridden in further-derived class

[james_avera2 at yahoo dot com]

------- Additional Comments From james_avera2 at yahoo dot com  2004-01-13 00:37 -------
Created an attachment (id=5468)
 --> (http://gcc.gnu.org/bugzilla/attachment.cgi?id=5468&action=view)
Test case


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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=13664

[Bug c++/13664] virtual in private base can be overridden in further-derived class

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2004-01-13 00:41 -------
Confirmed for 3.2.3 but fixed for 3.3.1 at least.

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |RESOLVED
           Keywords|                            |accepts-invalid
         Resolution|                            |FIXED
   Target Milestone|---                         |3.3.1


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=13664

[Bug c++/13664] virtual in private base can be overridden in further-derived class

[bangerth at dealii dot org]

------- Additional Comments From bangerth at dealii dot org  2004-01-13 16:10 -------
...to close it as invalid. 
W. 

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


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=13664

[Bug c++/13664] virtual in private base can be overridden in further-derived class

[bangerth at dealii dot org]

------- Additional Comments From bangerth at dealii dot org  2004-01-13 16:10 -------
The testcase is invalid but for other reasons. Overloading and access 
control are completely separate things. You can thus overload a function 
in the base class even if you can't access it. The error in 3.3 and 
3.4 is due to the fact that you try to take the address of base::i; 
overriding base::func by distant::func is still ok. 
 
I'll reopen the bug... 
 
W. 

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


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=13664