Re: Ada file depends on C file

[mockturtle <framefritti@gmail.com>]

On Sep 17, 3:07 pm, Ludovic Brenta <ludo...@ludovic-brenta.org> wrote:
> mockturtle wrote on comp.lang.ada:
>
>
>
>
>
> > Dear all,
> > I have a question that I am afraid is awfully trivial, but I spent
> > half a morning without finding any answer.
>
> > My setup: I am working with GPS and I have an Ada procedure (say
> > Interface_to_Addr in foo.adb) that needs to call a small C function
> > (char *interface_to_ip (char*)) defined in interface_to_ip.c.  So, in
> > my Ada code I wrote
>
> >    function interface_to_ip(interf : chars_ptr)  return chars_ptr;
> >    pragma Import(C, interface_to_ip);
>
> > Everything compiles fine, but when it is time to link, the linker
> > complains (correctly) that it cannot find "interface_to_ip".  The
> > problem is that the compiler does not know that interface_to_ip is in
> > interface_to_ip.c, or, in other words, it does not know that foo.adb
> > depends on interface_to_ip.c.
>
> > Currently I solved by adding the line
>
> >     pragma Linker_Options("../../interface_to_ip.o");
>
> > and by compiling "by hand" interface_to_ip.c to interface_to_ip.o, but
> > this solution is *UGLY*.
>
> > Everything would be fine if I could tell to the compiler that foo.adb
> > depends on interface_to_ip.c, but I do not know how to do it.  I
> > looked under the GPS "Project" menu, browsed the GNAT user & reference
> > manuals (although not in the deepest detail) and googled for a while,
> > but I could not find an answer.
>
> > Thank you in advance for your help.
>
> I normally use a Makefile to compile in such situations but there are
> two alternatives: gprmake and its successor, gprbuild. In GPS, you can
> specify that your project is multi-language; this will cause it to
> call the proper tool (instead of gnatmake, which is for Ada-only

I did.  If I open with an editor the .gpr file created by GPS I find
the line

   for Languages use ("Ada", "C");

> projects). I cannot be more specific as I don't use GPS myself.
> Hopefully the project manager interface in GPS should be intuitive
> enough.

Unfortunately I was not able to find any way to "logically connect"
the two files.
I must say that I am maybe using an old version (GPS 4.0.2 from
Help->About), maybe this is easier in the current version.  (For
several reasons,
I would avoid updating if possible)

>
> --
> Ludovic Brenta.