Re: [Boost-bugs] [Boost C++ Libraries] #4214: Use collection_size_type/version_type consistently (fixes Boost.MPI)

Subject: Re: [Boost-bugs] [Boost C++ Libraries] #4214: Use collection_size_type/version_type consistently (fixes Boost.MPI)
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2010-05-16 02:57:57

#4214: Use collection_size_type/version_type consistently (fixes Boost.MPI)
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  Reporter:  dgregor                  |       Owner:  ramey        
      Type:  Patches                  |      Status:  reopened     
 Milestone:  Boost 1.44.0             |   Component:  serialization
   Version:  Boost Development Trunk  |    Severity:  Problem      
Resolution:                           |    Keywords:               
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Changes (by ramey):

  * status:  closed => reopened
  * resolution:  fixed =>

Comment:

 I'm a little concerned that this might break the ability to read older
 archives.  Did you consider this?

 I think what may have happened is:

 a) I changed version_type unsigned char
 b) so an archive is created with a different type than before.
 c) then when things are read in - we read 16 bit int - error.
 d) so you've fixed it so that now it reads an 8 bit type. - no error on
 test.
 e) BUT - now any attempt to read an archive created in a previous system
 won't work - IT will have an error when it is trying to load.

 In short, I think I introduced a bug in 1.43 (or ? 1.42). and that now
 we've fixed it in the wrong place.  The best fix is likely:

 a) increment the value returned by get_libray_version()
 b) include conditional code around your fix.

 Does this make sense to you?

 Robert Ramey

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/4214#comment:3>
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