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From: ttwang@polyslo.CalPoly.EDU (Thomas Wang)
Newsgroups: comp.lang.c++
Subject: Re: copy objects to another location
Message-ID: <14285@polyslo.CalPoly.EDU>
Date: 11 Sep 89 17:48:18 GMT
Reply-To: ttwang@polyslo.CalPoly.EDU (Thomas Wang)
Distribution: usa
Organization: Cal Poly State University -- San Luis Obispo
Lines: 22

It is my impression that memcpy() work OK if the following things do not
happen:

1) The object to be moved does not contain physical pointers to itself.

2) The object to be moved does not contain physical pointers to other
   objects which could be moved.

These two requirements can be met in principle.  However there are nastier
problems.  If you are in the middle of an object's member function, and
that object gets moved, then 'this' will be pointing to the wrong place.

To solve this problem, you would either have to lock an object, or have
the ability to modify the value of 'this' to point to the correct place.

It does seem that 'copying garbage collection' is too much a hassle to
implement in C++.  I think I will stick to not moving any objects.

 -Thomas Wang (Ranma no baka!
                 - Ranma 1/2 )

                                                     ttwang@polyslo.calpoly.edu