Re: FFI again

[Eli Zaretskii <eliz@gnu.org>]

> From: Stefan Monnier <monnier@iro.umontreal.ca>
> Date: Sat, 05 Oct 2013 12:11:26 -0400
> 
> I think a "cheapish" way to do that is to make it possible for an ELPA
> package to come with a .c file that exports a "syms_of_module" function
> that can call things like defsubsr.
> 
> Installing such an ELPA package would require running a C compiler,
> obviously (unless we also provide some pre-compiled versions for
> particular target systems?).  And we'd need to add some function that
> can load the resulting compiled object (along with the .so libraries it
> depends on, since in many cases the whole purpose would be to call
> functions in those .so libs).

On Windows, having a foreign library call any of the functions
implemented within Emacs will require us to produce an import library,
as part of building Emacs.  It's easy to do that, and GNU Make in its
latest pretest already does something similar, but I thought I'd
mention that anyway.  When the .c file in question is linked into a
shared library, the import library will have to be passed to the
linker as one of the command-line arguments.