[Boost-bugs] [Boost C++ Libraries] #5119: [C++0x] unordered_map doesn't support cp-ctor.

Subject: [Boost-bugs] [Boost C++ Libraries] #5119: [C++0x] unordered_map doesn't support cp-ctor.
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2011-01-25 13:52:52

#5119: [C++0x] unordered_map doesn't support cp-ctor.
------------------------------+---------------------------------------------
 Reporter:  pluto@…           |       Owner:  danieljames
     Type:  Bugs              |      Status:  new        
Milestone:  To Be Determined  |   Component:  unordered  
  Version:  Boost 1.45.0      |    Severity:  Problem    
 Keywords:                    |  
------------------------------+---------------------------------------------
 hi,

 during compiling following testcase on gcc-4.6 snapshot i get an error.

 {{{#!c++
 #include <boost/unordered_map.hpp>

 struct S
 {
         boost::unordered_map<const void*, int > m_;
 };

 boost::unordered_map<const void*, S> m2_;

 void foo ( const void* p )
 {
         S s;
         m2_.insert ( std::make_pair ( p, s ) );
 }
 }}}

 {{{
 (...)
 include/c++/4.6.0/bits/stl_pair.h:110:17:
    error: 'constexpr std::pair<_T1, _T2>::pair(const std::pair<_T1, _T2>&)
    [with _T1 = const void* const, _T2 = S, std::pair<_T1, _T2>
       = std::pair<const void* const, S>]' is implicitly deleted because
           the default definition would be ill-formed:
 .../include/c++/4.6.0/bits/stl_pair.h:110:17:
    error: use of deleted function 'S::S(const S&)
 }}}

 the major problem is a lack of copy constructor in unordered_map when
 compiled with -std=gnu++0x. the !defined(BOOST_NO_RVALUE_REFERENCES)
 activates only move semantics while documentation describes cp-ctor.
 http://www.boost.org/doc/libs/1_45_0/doc/html/boost/unordered_map.html#id1354372-bb


 GCC bugzilla entry about this issue: http://gcc.gnu.org/PR47417

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/5119>
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