Re: [boost] [filesystem] regressions for operations_test

From: JOAQUIN LOPEZ MU?Z (joaquin_at_[hidden])
Date: 2004-11-01 12:52:58

----- Mensaje original -----
De: Beman Dawes <bdawes_at_[hidden]>
Fecha: Domingo, Octubre 31, 2004 11:03 pm
Asunto: Re: [boost] [filesystem] regressions for operations_test

> At 03:56 PM 10/31/2004, JOAQUIN LOPEZ MU?Z wrote:
> >Hi,
> >
> >msvc, msvc-stlport, iw-7_1-vc6
> >and iw-7_1-vc6-stlp-4_5_3 currently fail this
> >test (see for instance http://tinyurl.com/4xo4a).
> >I don't know for sure, but I've got the hunch this
> >might be related with the fact that 2004 is
> >a leap year and today we've had a 1-hour adjustment
> >in some countries due to the daylight saving policy.
> >These two facts combined might yield an offset
> >outside the expected range.
> >Just wanted to note this in case it might ring a
> >bell for somebody.
> 
> Or it might just be because offsets cross the daylight savings 
> time 
> boundary.
> 

Well, that's what I was saying. The leap year and the
cross-daylight saving issues combined will yield a
time difference of 366*24*3600+3600 seconds, off the
expected value by 1 hour.

> I'll wait until the tests have cycled again, and then take a look.
> 

If my theory's correct, these tests will revert to normal
by November 2. This phenomenon will happen again
2008, October 26 to 28, and 2012 October 28 to 30.
In 2016, however, the cross-daylight offset plays on
the subtracting raher than the adding side, so the
tests won't fail :) Excuse my indulgence on this
silly issue.

Joaquín M Lópeez Muñoz
Telefónica, Investigación y Desarrollo