Newsgroups: comp.lang.c++
Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!batcomputer!theory.tn.cornell.edu!lijewski
From: lijewski@theory.tn.cornell.edu (Mike Lijewski)
Subject: Re: The "new" Operator and the Copy Constructor
Message-ID: <1991Mar29.024933.21277@batcomputer.tn.cornell.edu>
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References: <1991Mar27.233549.1487@jpl-devvax.jpl.nasa.gov> <643@taumet.com>
Date: Fri, 29 Mar 1991 02:49:33 GMT

In article <643@taumet.com> steve@taumet.com (Stephen Clamage) writes:
>seq@jpl-devvax.jpl.nasa.gov (Sequence Folks) writes:
>
>|1) The compiler complains when I try to create an object from the heap
>|using the default copy constructor.
>|	class D {};
>|	D d;
>|	D* pd;
>|	pd = new D(d);
>
>This is a compiler bug.  The code should work, and does on other 
>compilers I tried.

I don't quite agree with Stephen here.  Why should this work?
Nowhere in the ARM can I find any indication that one is allowed to
explicitly call a default copy constructor.  Granted, it also isn't
explicitly disallowed, but considering all the examples and
commentary, what is one to think?  There is even a sentence in the
commentary which states that the default assignment operator needn't
be generated unless it's address is taken, which is analogous to the
default copy constructor situation.  My reading is basically that if
a situation calls for a copy constructor, the compiler will do the
"right thing".  Am I reading something into this that isn't there, or
could this be something that was intentionally left vague and up to
the compiler implementer?

>-- 
>
>Steve Clamage, TauMetric Corp, steve@taumet.com


-- 
Mike Lijewski  (H)607/272-0238 (W)607/254-8686
Cornell National Supercomputer Facility
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