On 2015-08-01 23:51, Thiago Macieira wrote: > QDateTime API accepts the offset from UTC in seconds, but all existing > timezones are multiples of a quarter hour. With a range from -12 to > +13.5, we > need ceil(log((13.5 + 12) * 4) / log(2)) = 7 bits for the timezone. > With the > one bit for the tag, we have 48 bits left for the msecs portion on > 64-bit > platforms. > > A 48-bit millisecond field spans 3257812 days. JD 3257812 is > 4207-06-27.
Actually you used 1 + 7 + 48 = 56 bits, which leave another 8 bits for useful data such as Spec. Or am I missing something obvious here? What is the recommended way to share a d-ptr with other data? By using a union on the d-ptr and a struct containing bit fields? > Anyone want to try this? > > Please note you cannot manipulate the this pointer in a member > function, so > all the QDateTimePrivate member functions need to be made static first. Regards, Mark Langezaal _______________________________________________ Development mailing list [email protected] http://lists.qt-project.org/mailman/listinfo/development
