On 9/29/2016 2:07 AM, Andreas Wehrmann wrote:

Hello folks,

I've just wanted to try out the new release and noticed that the Thread
library was not building.

Assuming this code:

#include <boost/thread.hpp>
int main( void )
{
    return 0;
}


When compiled with -std=c++0x the compilation fails with:

In file included from
./boost/boost_1_62_0/boost/exception/detail/exception_ptr.hpp:20:0,
                 from ./boost/boost_1_62_0/boost/exception_ptr.hpp:9,
                 from
./boost/boost_1_62_0/boost/thread/exceptional_ptr.hpp:10,
                 from ./boost/boost_1_62_0/boost/thread/future.hpp:25,
                 from ./boost/boost_1_62_0/boost/thread.hpp:24,
                 from test.cpp:2:
./boost/boost_1_62_0/boost/exception/info.hpp: In instantiation of
‘boost::error_info<boost::tag_original_exception_type, const
std::type_info*>’:
./boost/boost_1_62_0/boost/exception/detail/exception_ptr.hpp:95:32:
instantiated from here
./boost/boost_1_62_0/boost/exception/info.hpp:66:5: error: ‘class
boost::error_info<boost::tag_original_exception_type, const
std::type_info*>’ has no member named ‘value_’
./boost/boost_1_62_0/boost/container/detail/pair.hpp:85:30: warning:
‘boost::container::piecewise_construct’ defined but not used
[-Wunused-variable]
./boost/boost_1_62_0/boost/system/error_code.hpp:221:36: warning:
‘boost::system::posix_category’ defined but not used [-Wunused-variable]
./boost/boost_1_62_0/boost/system/error_code.hpp:222:36: warning:
‘boost::system::errno_ecat’ defined but not used [-Wunused-variable]
./boost/boost_1_62_0/boost/system/error_code.hpp:223:36: warning:
‘boost::system::native_ecat’ defined but not used [-Wunused-variable]


Compilation works if I don't use -std=c++0x.
The exact compiler version is "g++ (Ubuntu/Linaro 4.6.3-1ubuntu5) 4.6.3".
I'm aware that g++ 4.6.3 is not among the compilers tested for C++11,
but it is for pre-Cpp11;
I'm wondering if there is a reason for that which I might not be aware
of (any known problems?).

This looks like an rvalue references bug in gcc-4.6.3 since error_info definitely has a member named 'value_'.