An assertion bug with VC 8.0 is partially correct at least in the version I found in CVS. options_description.cpp revision=1.16.2.1 This calculation does not assume the indent in the line used. The line_length added produces longer line sequence as would fit in the line, so a line wrap occurs. The output looks somehow ugly: -v [--version] test line dkakal alalalala a sdk dkdkdkd instead of: -v [--version] test line dkakal alalalala a sdk dkdkdkd Current calc: LineNo. 393 // Take care to never increment the iterator past 394 // the end, since MSVC 8.0 (brokenly), assumes that 395 // doing that, even if no access happens, is a bug. 396 unsigned remaining = distance(line_begin, par_end); 397 string::const_iterator line_end = line_begin + 398 ((remaining < line_length) ? remaining : line_length); My proposal would be adding before the while loop (line 377): size_t offset = line_length - indent; LineNo. 393 // Take care to never increment the iterator past 394 // the end, since MSVC 8.0 (brokenly), assumes that 395 // doing that, even if no access happens, is a bug. 396 unsigned remaining = distance(line_begin, par_end); 397 string::const_iterator line_end = line_begin + 398 ((remaining < offset) ? remaining : offset); With Kind Regards, Ovanes Markarian With Kind Regards, Ovanes