c++/8500: Allows cast to private base class

[bangerth@dealii.org]

Synopsis: Allows cast to private base class

State-Changed-From-To: analyzed->closed
State-Changed-By: bangerth
State-Changed-When: Fri Nov  8 07:02:18 2002
State-Changed-Why:
    I think this is actually a duplicate of c++/2330.

http://gcc.gnu.org/cgi-bin/gnatsweb.pl?cmd=view%20audit-trail&database=gcc&pr=8500