Re: [boost] Re: serialization - build shared libs

From: martin.ecker_at_[hidden]
Date: 2004-09-07 07:04:57

Neal Becker wrote:
> Is this perhaps a MS-windows specific problem?  I did build a shared lib
> (using scons, I haven't learned jam yet), and AFAICT it is working, on
> Linux.

I'm pretty sure you will also run into problems with shared objects 
under Linux. The problem is that certain global variables (e.g. for 
the type registry) are defined as static member variables in header 
files. Under Windows, if two different DLLs include this header file, 
you will get two different copies of that static member variable - one 
in each DLL - although there should only be one. Maybe the linker 
under Linux is smart enough to resolve such issues.

Have you tried to serialize a class defined in one shared object 
(which is registered in the type registry via BOOST_CLASS_EXPORT) from 
code in another shared object? That's when you might run into 
problems. You definitely will under Windows.

You might also run into problems when you dynamically (i.e. explicitly 
in your code via dlopen) load a shared object, which contains classes 
that use BOOST_CLASS_EXPORT to register themselves. Again, under 
Windows you definitely will.

Regards,
Martin

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