id summary reporter owner description type status milestone component version severity resolution keywords cc 9550 gcc warn will break strict-aliasing rule in win_iocp_handle_service.ipp:49 anonymous chris_kohlhoff "{{{ In file included from C:/boost_1_55_0/boost/asio/detail/win_iocp_handle_service.hpp:319:0, from C:/boost_1_55_0/boost/asio/detail/win_iocp_serial_port_service.hpp:26, from C:/boost_1_55_0/boost/asio/serial_port_service.hpp:27, from C:/boost_1_55_0/boost/asio/basic_serial_port.hpp:30, from C:/boost_1_55_0/boost/asio/serial_port.hpp:24, C:/boost_1_55_0/boost/asio/detail/impl/win_iocp_handle_service.ipp: In constructor 'boost::asio::detail::win_iocp_handle_service::overlapped_wrapper::overlapped_wrapper(boost::system::error_code&)': C:/boost_1_55_0/boost/asio/detail/impl/win_iocp_handle_service.ipp:49:44: warning: dereferencing type-punned pointer will break strict-aliasing rules [-Wstrict-aliasing] *reinterpret_cast(&hEvent) |= 1; }}} I think that this problem can resolve by via lvalue char* type. {{{ char* comply_strict_aliasing_rule = reinterpret_cast(&hEvent); *reinterpret_cast(comply_strict_aliasing_rule) |= 1; }}}" Bugs closed To Be Determined asio Boost 1.55.0 Problem fixed