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From: jpotter@falcon.lhup.edu (John Potter)
Subject: Named return value optimisation- reprise.
Date: 1997/06/20
Message-ID: <199706192345.SAA24456@csrlink.net>#1/1
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X-Original-Date: Thu, 19 Jun 1997 22:52:39 GMT
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On 19 Jun 1997 09:06:42 PDT, bparker@gil.com.au (Brian Parker) wrote:

: However, as I have shown elsewhere in this thread, the same issues
: arise with the NRVO and RVO, albeit in a much more limited way.
               
Just trying to clear your terms.
	T f (T t) {
		T tmp(t);
		return tmp;
		}
Removing tmp and constructing the copy in the return value is called
"return value optimization" in D&E and MEC++.  It is called "named
return value optimization" by Lippman in IC++OM and C++Report.  Since
you are using both terms, I assume that they mean two different things
to you.
	T f (T t) {
		return T(t);
		}
I think that you are calling removal of the unnamed temporary from the
return RVO and the one above NRVO.  I think that these are two
different issues and the former requires 12.8/15 while the latter
requires only 12.2/1.  Could you clarify your terms?  I think that you
asked for clarification of that and other unnamed temp removals and
maybe someone else will address that.

John
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