Re: [boost] boost and 2007 US DST change

From: Graham Bennett (graham-boost_at_[hidden])
Date: 2007-01-10 16:34:51

On Wed, Jan 10, 2007 at 08:19:57AM -0700, Jeff Garland wrote:
> Graham Bennett wrote:
> > Hi,
> > 
> > I'm trying to evaluate whether some applications which use Boost are
> > exposed to problems with the change to the start and end dates of
> > Daylight Saving Time in the US this year
> > (http://en.wikipedia.org/wiki/Energy_Policy_Act_of_2005#Change_to_daylight_saving_time).
> > 
> >>From an initial inspection, it seems there are at least two areas which
> > may cause incorrect behaviour after the change is made:
> > 
> >  - There is a deprecated template class boost::date_time::us_dst_rules
> >    (http://www.boost.org/boost/date_time/dst_rules.hpp) which hard-codes
> > the rules for US DST changes.  Admittedly this class is deprecated, but
> > it remains in the code base.
> 
> True -- it should be updated as I know there are some users.

Ok, I'll have a go at making a patch.

> >  - Boost ships with a database of timezone and DST information in CSV
> >    format.  This appears to contain the old dates for the DST changeover
> > as reported here
> > http://sourceforge.net/tracker/index.php?func=detail&aid=1478619&group_id=7586&atid=207586.
> > 
> > Does the above seem right?  Also, have these problems been fixed in the
> > upcoming 1.34 release?  From a quick scan of CVS it seems not.
> 
> Nope, see other recent post on this topic.
> 
> > I'd also be grateful if people could comment on any other areas within
> > Boost that could be problematic, if any.
> > 
> > Lastly I wonder if it's worth perhaps summarising this on the Boost site
> > somewhere so that it's easier for others to find the information.
> 
> It should probably go in the date-time docs and the 1.34 release notes -- care 
> to write a summary blurb?

I'll try to send this along with the patch.

cheers,

Graham