id	summary	reporter	owner	description	type	status	milestone	component	version	severity	resolution	keywords	cc
12963	boost::time_period::span() returns invalid period if one of the periods is not-a-date-time	willi.burkhardt@…	az_sw_dude	"In some cases, the time_period::span() function returns a less than optimal result.
The expected behavior is that if one of the two periods is invalid/not-a-date-time the other is returned.

What I observed is that if one of the two source periods is not-a-date-time, the length() of the period returned is wrong/broken; invalidating the resulting time_period.

I might be wrong with my expectation above, but in this case it should be at least documented. Attached is a global function that I use to ""fix"" it in my code."	Bugs	new	To Be Determined	date_time	Boost 1.62.0	Problem		time_period span