No boost::promise<T>::set_value(const T&) overload present in C++03 mode

[rob.desbois@…]

When compiling in C++03 mode I am unable to use anything but a primitive type in a promise, and therefore also the dependent types in Boost.Thread

Minimal testcase:

#include <boost/thread/future.hpp>

struct foo {

foo(int i_): i(i_) {} int i;

};

int main() {

Clearly a const future ref isn't much use, but I needed to prove the problem wasn't me trying to copy a unique_future const boost::unique_future<foo>& fut =

boost::make_ready_future( foo(42) );

}

Output from g++ 4.8.2 with Boost 1.55 and -DBOOST_THREAD_USES_MOVE:

In file included from ../../deps/boost/include/boost/tuple/tuple.hpp:33:0,

from ../../deps/boost/include/boost/thread/detail/async_func.hpp:37, from ../../deps/boost/include/boost/thread/future.hpp:22, from t.cpp:2:

../../deps/boost/include/boost/tuple/detail/tuple_basic.hpp: In function ‘typename boost::tuples::access_traits<typename boost::tuples::element<N, boost::tuples::cons<HT, TT> >::type>::const_type boost::tuples::get(const boost::tuples::cons<HT, TT>&)’: ../../deps/boost/include/boost/tuple/detail/tuple_basic.hpp:228:45: warning: typedef ‘cons_element’ locally defined but not used [-Wunused-local-typedefs]

typedef BOOST_DEDUCED_TYPENAME impl::type cons_element;

In file included from ../../deps/boost/include/boost/bind/bind.hpp:29:0,

from ../../deps/boost/include/boost/bind.hpp:22, from ../../deps/boost/include/boost/thread/future.hpp:41, from t.cpp:2:

../../deps/boost/include/boost/bind/arg.hpp: In constructor ‘boost::arg<I>::arg(const T&)’: ../../deps/boost/include/boost/bind/arg.hpp:37:22: warning: typedef ‘T_must_be_placeholder’ locally defined but not used [-Wunused-local-typedefs]

typedef char T_must_be_placeholder[ I == is_placeholder<T>::value? 1: -1 ];

t.cpp: In function ‘int main()’: t.cpp:12:78: error: expected primary-expression before ‘f’

const boost::unique_future<foo>& fut = boost::make_ready_future( foo f(42) );

t.cpp:12:42: warning: unused variable ‘fut’ [-Wunused-variable]

const boost::unique_future<foo>& fut = boost::make_ready_future( foo f(42) );

In file included from ../../deps/boost/include/boost/system/system_error.hpp:14:0,

from ../../deps/boost/include/boost/thread/exceptions.hpp:22, from ../../deps/boost/include/boost/thread/pthread/mutex.hpp:12, from ../../deps/boost/include/boost/thread/mutex.hpp:16, from ../../deps/boost/include/boost/thread/future.hpp:24, from t.cpp:2:

../../deps/boost/include/boost/system/error_code.hpp: At global scope: ../../deps/boost/include/boost/system/error_code.hpp:222:36: warning: ‘boost::system::posix_category’ defined but not used [-Wunused-variable]

static const error_category & posix_category = generic_category();

../../deps/boost/include/boost/system/error_code.hpp:223:36: warning: ‘boost::system::errno_ecat’ defined but not used [-Wunused-variable]

static const error_category & errno_ecat = generic_category();

../../deps/boost/include/boost/system/error_code.hpp:224:36: warning: ‘boost::system::native_ecat’ defined but not used [-Wunused-variable]

static const error_category & native_ecat = system_category();

I have replicated this with Clang 3.4, also with Boost 1.54 on both compilers, and without -DBOOST_THREAD_USES_MOVE too. From the boost-users mailing list it looks like it has been replicated with 1.56 too.