* C:\upp\out\autotest\CLANGx64.Debug.Debug_Full\DoubleNull.exe 14.12.2020 10:29:29, user: cxl

IsNull(x) = true
IsNull(y) = false
IsNull(1e300) = false
IsNull(1e-320) = false
IsNull(DBL_MAX) = false
IsNull(0) = false
IsNull(log(-1)) = true
IsNull(1 / zero) = true
