Re: Win32 libltdl issue

[Ralf Wildenhues]

Hi Bob, Howard, others,

* Bob Friesenhahn wrote on Wed, Apr 27, 2005 at 06:34:47PM CEST:
> On Wed, 27 Apr 2005, Howard Chu wrote:
> >>
> >>Related question: Do I have to specify the declspec(export) in the same
> >>translation unit in which I define the function?  This is what bugs us
> >>in mingw ATM.  Specifying the declspec in another translation unit
> >>seems to work with cygwin but fail on mingw.  (Of course, the unit gets
> >>linked into the same lib in any case).
> >
> >Yes, I think so, but not entirely sure. Since all the code I work with 
> >always puts the declarations in a header file that every source file 
> >includes, it has never been an issue for me.
> 
> The declarations should be consistently applied across all translation 
> units in the same DLL.  If a function prototype is supplied, then it 
> should be appropriately scoped during compilation.

Well, just to satisfy this rule we would need to break binary
compatibility on win32, since the *_preloaded_symbols lists created on
the fly in `libtool' might need them.  As far as I understand, it would
be much easier though to do the right thing[tm] and replace them with
accessor functions right away.

This has the additional small benefit that we only need break once -- we
could do the accessor functions for object and functions symbols
correctly right away (TODO 1.2, first entry).

> >I see that more recent versions of cygwin/mingw appear to have made using 
> >declspec unnecessary:

> This assumes that libtool should only support the GCC compiler under 
> Windows.  Microsoft, Borland, and others, need not apply.  Is there a 
> good reason to rule out all compilers except for GCC?

I agree with Bob.  Unless there is compelling reason against keeping
support in, we should.  Obviously, there is no reason against optimizing
the case where we have a good linker either.

BTW: Does anyone have access to non-gcc compilers on win32 and some
incentive to test Libtool HEAD with them?  We need more test coverage
there (and probably a couple of patches, too).

Regards,
Ralf