[Boost-bugs] [Boost C++ Libraries] #4820: any swaps inefficiently

Subject: [Boost-bugs] [Boost C++ Libraries] #4820: any swaps inefficiently
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2010-11-07 02:26:46

#4820: any swaps inefficiently
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 Reporter:  jonathandodd@…          |       Owner:  nasonov     
     Type:  Bugs                    |      Status:  new         
Milestone:  To Be Determined        |   Component:  any         
  Version:  Boost 1.44.0            |    Severity:  Optimization
 Keywords:                          |  
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 Apologies if this isn't a bug - I am quite new to boost, however I checked
 in the IRC channel and it doesn't seem like this is a total non-starter.

 It seems that if you simply call swap, std::swap is called, resulting in
 an inefficient swapping operation. For example:

 Big b1, b2;
 any a1=b1, a2=b2;

 swap(a1,a2);    //Calls std::swap, invokes three copy constructors

 I've attached a demonstration file, which I compiled with gcc.

 Seems like can be easily solved with an overloaded std::swap, but I know
 little about boost, so I'll leave that for the experts :)

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Ticket URL: <https://svn.boost.org/trac/boost/ticket/4820>
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