[Bug c++/55813] New: Poorly named/documented option Wctor-dtor-privacy

["harald at gigawatt dot nl" <gcc-bugzilla@gcc.gnu.org>]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55813

             Bug #: 55813
           Summary: Poorly named/documented option Wctor-dtor-privacy
    Classification: Unclassified
           Product: gcc
           Version: 4.7.2
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: harald@gigawatt.nl


The -Wctor-dtor-privacy option is documented as

`-Wctor-dtor-privacy (C++ only)'
     Warn when a class seems unusable, because all the constructors or
     destructors in a class are private and the class has no friends or
     public static member functions.

However, the option warns for more than just that:

class A { // warning: all member functions in class 'A' are private
    void f();
};

class B { // no warning
    void f() {}
public:
    B() {}
};

The documentation does not explain why a warning for A is issued, nor does it
explain why A is treated differently from B. The option's name suggests that no
warning should be generated for either of them, but I cannot tell what the
actual intended behaviour is, only that gcc has behaved this way since before
3.x.