Re: GNAT and GNU build system

[Stephen Leake <stephen_leake@acm.org>]

Ludovic Brenta <ludovic.brenta@insalien.org> writes:

> Tapio Kelloniemi writes:
> > I would really prefer typing:
> > ./configure --prefix=/usr --enable-goldobj
> 
> I understand your concern completely.  My concern, though, is the
> sheer complecity of the ./configure script itself, and that of the
> Makefile it generates.  Most of that complexity is unnecessary with
> Ada programs, and in fact really gets in the way.  With Ada, you would
> normally want to take full advantage of GNAT project files.  The only
> places where ./configure may be of help are for the installation
> target (--prefix), and finding any Ada libraries you depend on.

This is true. So we need to start generating patches to auto* that
take advantage of Ada's simplicity. Not an easy task, but in the long
run it is the right solution.

Hmm. Maybe rewriting auto* in Ada first would be easier; I'm not
sure :).

> <plug mode=shameless>
> 
> This problem is solved nicely in Debian GNU/Linux.  Each library has a
> GNAT project file in a well-known location
> (/usr/share/ada/adalib/library.gpr).  Your program just "withs" them
> as required.

That sounds good. But Ada still needs to cooperate with autoconf.

> Furthermore, on non-Debian systems, the GNU Ada Environment
> Specification[1] says where library files should be installed.  Here
> again, you would not need a ./configure at all; just use -aI and -aO
> as necessary.

Only if you have a pure Ada project. I find this unlikely; I like
LaTeX or Texinfo for documentation, and I want my makefiles to run
test drivers.

> Since Debian follows the GNAE, your GNAT project file can be portable
> without the need for ./configure.

That's good.

-- 
-- Stephe