Re: [Mingw-users] exporting symbols from an archive (fwd)

[Jack D. <jjd...@da...>]

On Mon, 19 Jan 2004, Luke Dunstan wrote:
> 
> ----- Original Message ----- 
> From: "Justin Forest" <vh...@us...>
> To: <min...@li...>
> Sent: Monday, January 19, 2004 4:47 AM
> Subject: [Mingw-users] exporting symbols from an archive
> 
> 
> > Hello.
> >
> > I'm building a dynamic library from several *.o and *.a files.
> > Everything is normal except that symbols from *.a, even though they are
> > definde as __declspec(dllexport), are not exported.  The ones from *.o
> > files are, as expected.
> >
> > However, if I add a non-exported function like:
> >
> > void dummy(void)
> > {
> > a_function_from_ar(/* args */);
> > }
> >
> > Then the function is exported.  Is there a way to tell the linker to
> > export symbols from the archive, even if they are not referenced,
> > without using such a trick?
> 
> IMHO this is a bit outside the intended use of archives, so I am not
> surprised that it doesn't work. Perhaps the linker options "--undefined"
> and/or "--whole-archive" will help to achieve the same effect as your dummy
> function.
> 
> Luke

--whole-archive works for me.  One hint; it's a switch that applies
to archives after it in the link command line and can/should be
toggled off so you'll probably want something like:

$ gcc -shared -o mycode.dll -Wl,--whole-archive mycode.a \
   -Wl,--no-whole-archive otherarchive.a -lnetapi32 -lwsock32

The above example will pull in *all* the exported symbols 
from mycode.a but only *unresolved* symbols from otherarchive.a.

Hope this helps,

Jack D.
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