Re: [Boost-users] [Serialization] Linker error on BOOST_CLASS_EXPORTupgrading from 1.44.0

Subject: Re: [Boost-users] [Serialization] Linker error on BOOST_CLASS_EXPORTupgrading from 1.44.0
From: Enrico Carrara (enrico.ecamail_at_[hidden])
Date: 2011-08-01 12:02:29

On Fri, Jul 29, 2011 at 6:35 PM, Robert Ramey <ramey_at_[hidden]> wrote:

> I'm going to guess that there's too much instatiation going on.
>

I agree

>  Try the
> following:
>

a) try changing the headers so they don't inlcude inline functions.  Put
> definitions in a separate cpp or ipp file.
>

Yes, I already have (almost) all inline code outside headers. I'll revise it
further.

>

b) since a is a huge amount of work.  Try this:  build your above
> module a little at a time.  That is - comment out most of the headers
> and try to build - of course it will fail to link.  Add headers until
> it starts to have the problem.  The basic goal is to find which
> templates are being "accdently instantiated multiple times.
>
> Doing as you wisely suggest, I noticed that the compiler's heap seems to
blow up when trying to produce code for template member function "serialize"
of some specific classes, which are are roots of containment structures made
out of lists, vectors and maps of shared_ptr to other objects, which are in
turn a composition of other objects. The containment structures is 3-4
levels deep. Think of it as a "Sketch" root object, containing a list of
shared_ptr to "Polyline", each containing a list of shared_ptr to
"LineSegment" or "ArcSegment", each containing a pair of "Point" and some
more data. When the compiler parses/generates code for "Sketch::serialize",
about two gigabytes of memory are allocated.

I found a workaround, anyway, tweaking some compiler optimizations. I also
revised all the header files and moved some code outside, then isolated all
BOOST_CLASS_EXPORT_IMPLEMENTs in one .cpp and moved any other serialization
code in other two cpp. This seems to have solved my problem.

Unfortunately, I haven't found a more effective strategy for reducing code
bloat, so I am ready to accept/try any further advice in this regard.

Thanks again for your advices.
Enrico