Path: utzoo!telly!attcan!uunet!tut.cis.ohio-state.edu!MCC.COM!rfg
From: rfg@MCC.COM (Ron Guilmette)
Newsgroups: gnu.g++.bug
Subject: BUG(s) in G++ 1.34.0 - missing errors (again)
Message-ID: <8903102231.AA07752@riunite.aca.mcc.com>
Date: 10 Mar 89 22:31:58 GMT
Sender: daemon@tut.cis.ohio-state.edu
Distribution: gnu
Organization: GNUs Not Usenet
Lines: 74


This bug report (for G++ 1.34.0/Sun3) is very much like my previous one about
private constructors, except this one is about private destructors.

In either case, the programmer should be allowed to make certain operations
of a given class (such as assignment, construction, and destruction) illegal
outside of the class just by declaring these operations within the private
part of the class declaration.

Unfortunately, g++ doesn't (currently) let you control the visibility of
constructors or destructors this way.  These operations remain accessable
anywhere regardless of their public or private status.

The following code demonstrates this.  I believe that all of the lines
marked with // ERROR should have errors messages issued for them because
these are the places where base::~base() gets (implicitly) called.

Following the code is a compilation log.

Cut here
------------------------------------------------------------------------------
/*
Description - check that if a destructor is needed (e.g. at the point
		where an object is destroyed) and that if there is a destructor
		for the class of the object, but it is private, a reasonable
		error message is issued.

		Cases: objects which are: (1) static (2) auto (3) heap.

		Cases: objects of (1) a type which has a private default
		    constructor, and (2) objects of a type derived from a type
		    which has a private default constructor.
*/

class base
{
    ~base();
    friend class friendly;
};

static base static_base_object_1;		// ERROR
base static_base_object_2;			// ERROR

void f1 ()
{
	base local_base_object;
	base *base_ptr = new base;

	return;					// ERROR, ERROR
}
 
class derived : base
{
public:
    ~derived();
};

static derived static_derived_object_1;		// ERROR
derived static_derived_object_2;		// ERROR

void f2()
{
	derived local_derived_object;
	derived *derived_ptr = new derived;

	return;					// ERROR, ERROR
}
----------------------------------------------------------------------------------
g++  -S -v x03.cc
g++ version 1.34.0.0
 /usr/local/src/lib/1.34.0.0/sun3/gcc-cpp -+ -v -undef -D__GNU__ -D__GNUG__ -Dmc68000 -Dsun -Dunix -D__mc68000__ -D__sun__ -D__unix__ -D__HAVE_68881__ -Dmc68020 x03.cc /tmp/cca07729.cpp
GNU CPP version 1.34.0.0
 /usr/local/src/lib/1.34.0.0/sun3/gcc-c++ /tmp/cca07729.cpp -quiet -dumpbase x03.cc -noreg -version -o x03.s
GNU C++ version 1.34.0.0 (68k, MIT syntax) compiled by GNU C version 1.33.