Re: [Boost-bugs] [Boost C++ Libraries] #4533: timespec translation fails for times before 1970

Subject: Re: [Boost-bugs] [Boost C++ Libraries] #4533: timespec translation fails for times before 1970
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2011-12-09 17:44:45

#4533: timespec translation fails for times before 1970
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  Reporter:  Philipp Huber <phu@…>            |       Owner:  viboes       
      Type:  Bugs                             |      Status:  assigned     
 Milestone:  To Be Determined                 |   Component:  thread       
   Version:  Boost 1.43.0                     |    Severity:  Problem      
Resolution:                                   |    Keywords:  absolute time
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Comment (by viboes):

 Replying to [comment:8 phu@…]:
 > Replying to [comment:7 viboes]:
 > > Replying to [comment:6 phu@…]:
 > >
 > > Thanks for the explanation. IIUC,and if you where using directly the
 underlying platform you will need to make sure that the time given satisfy
 the interface constraints ...
 > Well, we have a correct linux system time. Even if it shows the year
 1919, I think it perfectly satisfy the interface constraints. Well, I
 might be a bit naive on that point.
 > > ... and when you did a difference you will ensure that the seconds and
 nanoseconds will be positive, isn't it?
 > We subtract two ptime values. I expect the value to be usable for
 further operations. I would not check every subtraction for its correct
 value (whether its components are positive or not), that is what I expect
 of the operation to do.
 > >

 What do you use to make this difference? Boost.Date?

 > > I think that you will do the same when using Boost.Chrono. The best I
 can do is to add an assertion so that the modification doesn't add code on
 release mode.
 > Sorry, but I might be misunderstanding this point. If we end up with an
 assertion instead of a working program flow, I'm not exactly happy with
 the solution. Then I prefer you do nothing at all and we continue the way
 we did so far.

 The question is if the ptime given as parameter must be a valid one, that
 is, if it is a precondition. IMO, this is the spirit of a lot of standard
 functions, so that the implementation is not required to test the validity
 of the informations received in the parameters.

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/4533#comment:9>
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