Given this program fragment (based on the Getting Started example) using Boost::program_options compiled with MinGW: options_description desc("Program options"); ... variables_map vm; store(parse_command_line(argc, argv, desc), vm); gave the following error (reformatted for readability): error: no matching function for call to `store(boost::program_options::basic_parsed_options<const char>, boost::program_options::variables_map&)' candidates are: store(const boost::program_options::basic_parsed_options<char>&, boost::program_options::variables_map&, bool) store(const boost::program_options::basic_parsed_options<wchar_t>&, boost::program_options::variables_map&) I can add a "true" as a third argument to store(), but the mismatch still remains in the first argument: <const char> versus <char>&. If I assigned the result of parse_command_line() to an intermediate variable, I can match the &, but the const char versus char still remains. What is the problem way of calling store()? Merrill