id	summary	reporter	owner	description	type	status	milestone	component	version	severity	resolution	keywords	cc
5119	[C++0x] unordered_map doesn't support cp-ctor.	pluto@…	Daniel James	"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"	Bugs	closed	Boost 1.47.0	unordered	Boost 1.45.0	Problem	fixed		denis.arnaud_boost@…