id summary reporter owner description type status milestone component version severity resolution keywords cc 12708 Cannot use Boost Units cmath.hpp with custom systems Kamil Rojewski Matthias Schabel "When creating a new, custom unit sustem in Boost Units using boost::units::make_system, there's an issue when including cmath.hpp: {{{ In file included from boost/boost/units/cmath.hpp:29: In file included from boost/boost/units/systems/si/plane_angle.hpp:14: In file included from boost/boost/units/systems/si/base.hpp:20: In file included from boost/boost/units/base_units/si/meter.hpp:17: /boost/boost/units/base_unit.hpp:108:9: error: functions that differ only in their return type cannot be overloaded check_double_register(const units::base_unit_ordinal&) ^ Common/Units.h:26:15: note: in instantiation of template class 'boost::units::base_unit >, boost::units::dimensionless_type>, -9, void>' requested here : boost::units::base_unit ^ boost/boost/units/base_unit.hpp:108:9: note: previous declaration is here check_double_register(const units::base_unit_ordinal&) ^ boost/boost/units/base_unit.hpp:114:9: error: redefinition of 'boost_units_unit_is_registered' }}} As you can see, cmath includes the full si system and you cannot make your own after that." Bugs new To Be Determined units Boost 1.62.0 Problem