id	summary	reporter	owner	description	type	status	milestone	component	version	severity	resolution	keywords	cc
12525	cpp_bin_float: Anal fixation. Part 2. Sign of trunc(x) for x in range (-1..0)	Michael Shatz	John Maddock	"trunc(x) for x in range (-1..0).

I have no idea what IEEE-754 says about it, but I see that in practice all sane implementations return -0.

Except for boost::cpp_bin_float.
"	Feature Requests	closed	Boost 1.63.0	multiprecision	Boost 1.62.0	Cosmetic	fixed