Re: [Boost-bugs] [Boost C++ Libraries] #11835: boost::has_trivial_copy is incorrect on Clang

Subject: Re: [Boost-bugs] [Boost C++ Libraries] #11835: boost::has_trivial_copy is incorrect on Clang
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2015-12-12 18:31:39

#11835: boost::has_trivial_copy is incorrect on Clang
-------------------------+-------------------------------------------------
  Reporter:              |      Owner:  johnmaddock
  joseph.thomson@…       |     Status:  closed
      Type:  Bugs        |  Component:  type_traits
 Milestone:  To Be       |   Severity:  Problem
  Determined             |   Keywords:  has_trivial_copy clang memcpy
   Version:  Boost       |  is_trivially_copyable
  1.59.0                 |
Resolution:  wontfix     |
-------------------------+-------------------------------------------------
Changes (by johnmaddock):

 * status:  new => closed
 * resolution:   => wontfix

Comment:

 The point here is that has_trivial_copy is a Boost-specific trait so we
 can do what we want, and much more importantly: defining non-copyable
 types as trivially copyable drives a coach and horses through type safety,
 and leads to downright nasty and pernicious bugs.  The original bug report
 you referenced is one such - types that are moveable but not copyable
 should never, ever be memcpy'd.  If they are, then bad things typically
 happen.  I may add a note to the docs to this effect, but the more I think
 about this the less inclined I am to make any change to current behaviour.

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/11835#comment:3>
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