Re: [Boost-bugs] [Boost C++ Libraries] #1910: function::swap should avoid doing memory allocations

Subject: Re: [Boost-bugs] [Boost C++ Libraries] #1910: function::swap should avoid doing memory allocations
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2008-09-05 15:41:45

#1910: function::swap should avoid doing memory allocations
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  Reporter:  niels_dekker  |       Owner:  dgregor 
      Type:  Bugs          |      Status:  new     
 Milestone:  Boost 1.36.0  |   Component:  function
   Version:  Boost 1.35.0  |    Severity:  Problem 
Resolution:                |    Keywords:          
---------------------------+------------------------------------------------

Comment(by dgregor):

 This patch should give a significant performance improvement for swap().
 Note, however, that it does not provide the nothrow guarantee for swap()
 due to the small-object optimization: small objects are still copied by
 move_assign, so their constructors could throw. We may or may not want a
 no-throw swap for Boost.Function, regardless of what std::(tr1::)function
 say; that we can handle on-list.

 I'm applying a variant of this patch to trunk now, and will close the
 ticket then.

-- 
Ticket URL: <http://svn.boost.org/trac/boost/ticket/1910#comment:2>
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