[Boost-users] Compiler warnings when using boost::accumulators with gcc

Subject: [Boost-users] Compiler warnings when using boost::accumulators with gcc
From: Rob Wheeler (wheeler_at_[hidden])
Date: 2009-08-03 15:45:53

If I turn on gcc's -Wextra option when compiling code that uses an
accumulator with tag::max, I get a screen full of compiler warnings:

[wheeler_at_cib: /var/tmp/acc] cat acc.cpp
#include <iostream>
#include <boost/accumulators/accumulators.hpp>
#include <boost/accumulators/statistics/stats.hpp>
#include <boost/accumulators/statistics/max.hpp>
using namespace boost::accumulators;

int main()
{
    accumulator_set<double, stats<tag::max> > acc;

    acc(1.2);
    acc(2.3);
    acc(3.4);
    acc(4.5);

    std::cout << "Max: " << max(acc) << std::endl;

    return 0;
}

[wheeler_at_cib: /var/tmp/acc] g++ -W -I /opt/ros/include/boost-1_37/ acc.cpp
-o acc
/opt/ros/include/boost-1_37/boost/concept_check.hpp: In instantiation of
‘boost::UnaryFunction<boost::numeric::functional::as_min<const double,
void>, double, const double&>’:
/opt/ros/include/boost-1_37/boost/concept/detail/has_constraints.hpp:40:
instantiated from ‘const bool
boost::concept::not_satisfied<boost::UnaryFunction<boost::numeric::functional::as_min<const
double, void>, double, const double&> >::value’
/opt/ros/include/boost-1_37/boost/concept/detail/has_constraints.hpp:43:
instantiated from
‘boost::concept::not_satisfied<boost::UnaryFunction<boost::numeric::functional::as_min<const
double, void>, double, const double&> >’
/opt/ros/include/boost-1_37/boost/mpl/if.hpp:67:   instantiated from
‘boost::mpl::if_<boost::concept::not_satisfied<boost::UnaryFunction<boost::numeric::functional::as_min<const
double, void>, double, const double&> >,
boost::concept::constraint<boost::UnaryFunction<boost::numeric::functional::as_min<const
double, void>, double, const double&> >,
boost::concept::requirement<boost::UnaryFunction<boost::numeric::functional::as_min<const
double, void>, double, const double&> > >’
/opt/ros/include/boost-1_37/boost/concept/detail/general.hpp:19:
instantiated from ‘boost::concept::requirement_<void
(*)(boost::UnaryFunction<boost::numeric::functional::as_min<const double,
void>, double, const double&>)>’
/opt/ros/include/boost-1_37/boost/accumulators/numeric/detail/function1.hpp:67:
instantiated from ‘typename
boost::detail::function1<F>::result<boost::detail::function1<F> ()(const
A0&)>::type boost::detail::function1<F>::operator()(const A0&) const [with
A0 = double, F =
boost::numeric::functional::as_min<mpl_::arg<-0x00000000000000001>,
boost::numeric::functional::tag<mpl_::arg<-0x00000000000000001> > >]’
/opt/ros/include/boost-1_37/boost/accumulators/statistics/max.hpp:36:
instantiated from
‘boost::accumulators::impl::max_impl<Sample>::max_impl(const Args&) [with
Args =
boost::parameter::aux::arg_list<boost::parameter::aux::tagged_argument<boost::accumulators::tag::accumulator,
boost::accumulators::accumulator_set<double,
boost::accumulators::stats<boost::accumulators::tag::max, mpl_::na,
mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na,
mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na,
mpl_::na, mpl_::na, mpl_::na, mpl_::na>, void> >,
boost::parameter::aux::empty_arg_list>, Sample = double]’
/opt/ros/include/boost-1_37/boost/accumulators/framework/depends_on.hpp:282:
instantiated from
‘boost::accumulators::detail::accumulator_wrapper<Accumulator,
Feature>::accumulator_wrapper(const Args&) [with Args =
boost::parameter::aux::arg_list<boost::parameter::aux::tagged_argument<boost::accumulators::tag::accumulator,
boost::accumulators::accumulator_set<double,
boost::accumulators::stats<boost::accumulators::tag::max, mpl_::na,
mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na,
mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na,
mpl_::na, mpl_::na, mpl_::na, mpl_::na>, void> >,
boost::parameter::aux::empty_arg_list>, Accumulator =
boost::accumulators::impl::max_impl<double>, Feature =
boost::accumulators::tag::max]’
/opt/ros/include/boost-1_37/boost/accumulators/framework/depends_on.hpp:215:
instantiated from ‘static boost::fusion::cons<typename
boost::fusion::result_of::value_of<Iterator>::type, typename
boost::accumulators::detail::build_acc_list<typename
boost::fusion::result_of::next<Iterator>::type, Last,
boost::fusion::result_of::equal_to<typename
boost::fusion::result_of::next<Iterator>::type,Last>::value>::type>
boost::accumulators::detail::build_acc_list<First, Last, false>::call(const
Args&, const First&, const Last&) [with Args =
boost::parameter::aux::arg_list<boost::parameter::aux::tagged_argument<boost::accumulators::tag::accumulator,
boost::accumulators::accumulator_set<double,
boost::accumulators::stats<boost::accumulators::tag::max, mpl_::na,
mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na,
mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na,
mpl_::na, mpl_::na, mpl_::na, mpl_::na>, void> >,
boost::parameter::aux::empty_arg_list>, First =
boost::fusion::mpl_iterator<boost::mpl::v_iter<boost::mpl::v_item<boost::accumulators::detail::accumulator_wrapper<boost::accumulators::impl::max_impl<double>,
boost::accumulators::tag::max>, boost::mpl::vector0<mpl_::na>, 0>, 0l> >,
Last =
boost::fusion::mpl_iterator<boost::mpl::v_iter<boost::mpl::v_item<boost::accumulators::detail::accumulator_wrapper<boost::accumulators::impl::max_impl<double>,
boost::accumulators::tag::max>, boost::mpl::vector0<mpl_::na>, 0>, 1l> >]’
/opt/ros/include/boost-1_37/boost/accumulators/framework/depends_on.hpp:234:
instantiated from ‘typename
boost::accumulators::detail::meta::make_acc_list<Sequence>::type
boost::accumulators::detail::make_acc_list(const Sequence&, const Args&)
[with Sequence =
boost::mpl::v_item<boost::accumulators::detail::accumulator_wrapper<boost::accumulators::impl::max_impl<double>,
boost::accumulators::tag::max>, boost::mpl::vector0<mpl_::na>, 0>, Args =
boost::parameter::aux::arg_list<boost::parameter::aux::tagged_argument<boost::accumulators::tag::accumulator,
boost::accumulators::accumulator_set<double,
boost::accumulators::stats<boost::accumulators::tag::max, mpl_::na,
mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na,
mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na,
mpl_::na, mpl_::na, mpl_::na, mpl_::na>, void> >,
boost::parameter::aux::empty_arg_list>]’
/opt/ros/include/boost-1_37/boost/accumulators/framework/accumulator_set.hpp:145:
instantiated from ‘boost::accumulators::accumulator_set<Sample, Features,
Weight>::accumulator_set() [with Sample = double, Features =
boost::accumulators::stats<boost::accumulators::tag::max, mpl_::na,
mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na,
mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na,
mpl_::na, mpl_::na, mpl_::na, mpl_::na>, Weight = void]’
acc.cpp:9:   instantiated from here
/opt/ros/include/boost-1_37/boost/concept_check.hpp:325: warning: non-static
reference ‘const double&
boost::UnaryFunction<boost::numeric::functional::as_min<const double, void>,
double, const double&>::arg’ in class without a constructor