Re: [Boost-users] boost serialization archive compatibility

Subject: Re: [Boost-users] boost serialization archive compatibility
From: Robert Ramey (ramey_at_[hidden])
Date: 2010-06-24 12:38:16

Markus Henschel wrote:
> Hello group!
>
> We are upgrading boost from version 1.34.1 to 1.43.0. A quick test
> revealed that after the upgrade our binary archives cannot be loaded
> anymore. It seems like the type of the class id was changed from int
> to short making the old archive from 1.34.1 incompatible to our
> current application using 1.43.0. Is this a bug or expected behavior?

This would be contrary to the intention of maintaining backward 
compatibility.

> How does boost serialization treat backwards compatibility? Will
> archives created by earlier versions of the library be still
> loadable?

They are meant to be.

> Do different archives behave differently in this regard?

The archive classes included with the library are meant all work
exactly the same way.

> We do not really require backwards compatibility. I would just like to
> know what to expect.

That's a relief!!!  But I'm interested in finding more about this.

I believe that as an unintended consequence of "fixing" all level 4 warnings
I made this change in 1.43 and didn't foresee this issue.  I'll look into 
it.

Robert Ramey