(in theory correct rounding can be achieved but with big implementation cost,
see <a href="http://lipforge.ens-lyon.fr/www/crlibm/">crlibm</a>)
<li>At least the following functions must be correctly rounded:
-ceil, copysign, fabs, fdim, floor, fma, fmax, fmin, frexp, ldexp,
+ceil, copysign, fabs, fdim, floor, fma, fmax, fmin, frexp, ldexp, logb,
modf, nearbyint, nextafter, nexttoward, rint, round, scalbln, scalbn,
sqrt, trunc.
<li>Mathematical properties of functions should be as expected