c++/5086: -Wctor-dtor-privacy gives spurious warnings

[llib at computer dot org]

>Number:         5086
>Category:       c++
>Synopsis:       -Wctor-dtor-privacy gives spurious warnings
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    unassigned
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Tue Dec 11 21:16:01 PST 2001
>Closed-Date:
>Last-Modified:
>Originator:     Bill Clarke
>Release:        3.0.2
>Organization:
>Environment:
sparc-sun-solaris2.8
>Description:
the documentation for -Wctor-dtor-privacy says:
"`-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, -Wctor-dtor-privacy gives spurious warnings when the first public member function is not static.  see the attached file (test-ctor-dtor-privacy.cc) in which the class ExhibitsCtorDtorPrivacyBug produces the "warning" but class DoesNotExhibitBug does not.

-Wctor-dtor-privacy is included in -Wall, and so is worth fixing (imo).  
>How-To-Repeat:
compile attachment (test-ctor-dtor-privacy.cc, has no includes) with:
$ g++ -Wctor-dtor-privacy -c test-ctor-dtor-privacy.cc
test-ctor-dtor-privacy.cc:1: warning: `class ExhibitsCtorDtorPrivacyBug' only 
   defines private constructors and has no friends
$ 
>Fix:
the workaround is to put a static member function as the first public member.
an alternative fix is to change the documentation (-:
>Release-Note:
>Audit-Trail:
>Unformatted:
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