id	summary	reporter	owner	description	type	status	milestone	component	version	severity	resolution	keywords	cc
4708	regex::sub_match::length()	robin.snyder@…	John Maddock	"code does not match documentation. if matched==false length() does not return 0, instead it results in an assertion of ""string iterators incompatible""
docs state:
{{{
static difference_type length();

Effects: returns the length of this matched sub-expression, or 0 if this sub-expression was not matched: matched ? distance(first, second) : 0). 
}}}

Checked the source, code is broke.
"	Bugs	closed	To Be Determined	regex	Boost 1.44.0	Problem	fixed	regex sub_match length