[Boost-users] [program_options] strange assertions

9 Aug 2006

      Hi!

I use MS VC8.0 (2005) Express Edition.

This code sample causes the following assertion:

int main(int argc, char* argv[])
{
    options_description generic("Generic options");
    generic.add_options()
        ("version,v", "print version string")
        ("help,h", "produce help message")
        ;

    // Declare a group of options that will be
    // allowed both on command line and in
    // config file
    options_description config("Configuration");
    config.add_options()
		("worker-threads,w", po::value<int>()->default_value(20), "Each worker thread starts parsing of
one file.\ndefault: 20")
		;

	options_description cmdline_opt, cfgf_opt;
	cmdline_opt.add(generic).add(config);
	cfgf_opt.add(config);

	variables_map vm;
	store(command_line_parser(argc, argv).options(cmdline_opt).run(), vm);

	ifstream ifs("scanning_options.cfg");
	store(parse_config_file(ifs, cfgf_opt), vm);
	notify(vm);

	if(vm.count("help"))
		cout << config << endl;

    //... some other code

    return 0;
}

In this line:
	cout << config << endl;

I receive an assertion:

Debug Assertion Failed!

Program: e:\projects\...\protocol_scanner.exe
File: e:\program files\microsoft visual studio 8\vc\include\xstring
Line: 173

Expression: ("_Myptr + _Off <= (((_Mystring *)this->_Mycont)->_Myptr() + ((_Mystring
*)this->_Mycont)->_Mysize) && _Myptr + _Off >= ((_Mystring*)this->_Mycont)->_Myptr()",0)

...

line 173 is part of a function in xstring

	_Myt& __CLR_OR_THIS_CALL operator+=(difference_type _Off)
		{	// increment by integer
		if (this->_Mycont != _IGNORE_MYCONT)
		{
			_SCL_SECURE_VALIDATE(this->_Mycont != NULL);
			_SCL_SECURE_VALIDATE_RANGE(
				_Myptr + _Off <= (((_Mystring *)this->_Mycont)->_Myptr() + ((_Mystring
*)this->_Mycont)->_Mysize) &&
				_Myptr + _Off >= ((_Mystring *)this->_Mycont)->_Myptr()); // <- line 173
		}
		_Myptr += _Off;
		return (*this);
		}

Output in stdout window looks like:

Generic options:
  -v [ --version ]      print version string
  -h [ --help ]         produce help message

Configuration:
  -w [ --worker-threads ] arg (=20)

-------------------------^^^^^^^^^^ this looks really weired!!! Here should be another message.

Last line is really weired...

Stack trace is:
...
protocol_scanner.exe!std::_String_const_iterator & os={...},
std::basic_string par="Each worker thread
starts parsing of one file.", unsigned int first_column_width=36, unsigned int line_length=79) 
Line 381 + 0x28 bytes	C++
protocol_scanner.exe!boost::program_options::`anonymous
namespace'::format_description(std::basic_ostream & os={...}, const
std::basic_string & desc="Each worker thread
starts parsing of one file.\ndefault: 20", unsigned int first_column_width=36, unsigned int
line_length=79)  Line 453 + 0x34 bytes	C++

protocol_scanner.exe!boost::program_options::`anonymous
namespace'::format_one(std::basic_ostream & os={...}, const
boost::program_options::option_description & opt={...}, unsigned int first_column_width=36,
unsigned int line_length=80)  Line 489 + 0x1a bytes	C++
 	protocol_scanner.exe!boost::program_options::options_description::print(std::basic_ostream
...
& os={...})  Line 522 + 0x1e bytes	C++
   protocol_scanner.exe!boost::program_options::operator<<(std::basic_ostream
Parameter of executable is:
 --help

With Kind Regards,

Ovanes Markarian