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17/10/2007, 18h53

On 16 Oct, 23:26, "terminator(jam)" <farid.mehr...@gmail.com> wrote:
> A foo(){
> A ret;//this will be return under any conditions.
> //....
> return ret;//pre return :no copy/move};
>
> class A a=foo();//after return : copy/move to a

This is not the case. If the compiler correctly implements NRVO, the
example above will result in a single construction of A using the
default constructor, and then a subsequent destruction. No copies or
moves are made at any point.

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17/10/2007, 18h53	#3
int19h@gmail.com Messages: n/a Hébergeur:	Re: pre return optimization On 16 Oct, 23:26, "terminator(jam)" <farid.mehr...@gmail.com> wrote: > A foo(){ > A ret;//this will be return under any conditions. > //.... > return ret;//pre return :no copy/move}; > > class A a=foo();//after return : copy/move to a This is not the case. If the compiler correctly implements NRVO, the example above will result in a single construction of A using the default constructor, and then a subsequent destruction. No copies or moves are made at any point. --- [ comp.std.c++ is moderated. To submit articles, try just posting with ] [ your news-reader. If that fails, use mailto:std-c++@ncar.ucar.edu ] [ --- Please see the FAQ before posting. --- ] [ FAQ: http://www.comeaucomputing.com/csc/faq.html ]