Re: [Boost-bugs] [Boost C++ Libraries] #2819: boost::posix_time::hours, minutes, and seconds assume sizeof(long) == sizeof(int)

Subject: Re: [Boost-bugs] [Boost C++ Libraries] #2819: boost::posix_time::hours, minutes, and seconds assume sizeof(long) == sizeof(int)
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2010-07-29 17:32:02

#2819: boost::posix_time::hours, minutes, and seconds assume sizeof(long) ==
sizeof(int)
-----------------------------------+----------------------------------------
  Reporter:  pelee@…               |       Owner:  az_sw_dude
      Type:  Bugs                  |      Status:  new       
 Milestone:  Boost 1.39.0          |   Component:  date_time 
   Version:  Boost Release Branch  |    Severity:  Problem   
Resolution:                        |    Keywords:            
-----------------------------------+----------------------------------------

Comment (by Rob Stewart <robert.stewart@…>):

 I just ran afoul of this impedance mismatch yet again.  The value fit
 long, but not int, the underlying type of time_duration::sec_type in this
 case.  The truncation caused a large negative value to be treated as a
 sizable positive value silently creating a future rather than past time.

 I think the proper solution is to change the classes to use the typedefs
 from the base class, giving the following:

 {{{
   class hours : public time_duration
   {
   public:
     explicit hours(hour_type h) :
       time_duration(h,0,0)
     {}
   };

   class minutes : public time_duration
   {
   public:
     explicit minutes(min_type m) :
       time_duration(0,m,0)
     {}
   };

   class seconds : public time_duration
   {
   public:
     explicit seconds(sec_type s) :
       time_duration(0,0,s)
     {}
   };
 }}}

 Ensuring values fit within those types then becomes the caller's
 responsibility; !DateTime won't silently truncate or otherwise alter them.

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/2819#comment:3>
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