Re: how to extend the Makefile templates?

[Ralf Wildenhues]

Hi Harald,

* Harald Dunkel wrote on Wed, Aug 17, 2005 at 10:15:57AM CEST:
> Ralf Wildenhues wrote:
> > * Harald Dunkel wrote on Tue, Aug 16, 2005 at 12:39:46PM CEST:
> > 
> >>I would need some way to add recursive targets to all generated
> >>Makefiles, without asking every owner of every Makefile.am
> >>to append some include statement or some keyword to be replaced
> >>by AC_SUBST_FILE.
*snip*

> > For other people (e.g. me), requirements such as above would be much
> > easier to understand if a good reason for it was given as well.
> > I mean, what is it that prevents you from doing something like this
> > 
> >   find $top_srcdir -name Makefile.am | while read file
> >   do
> >     echo 'include $top_srcdir/some_snippet.am' >>"$file"
> >   done
> > 
> 
> This would assume that I am allowed to change the foreign
> Makefile.am files,

Yes.  What prevents this?

> it assumes that this command wasn't run before,

This can easily be checked.  You also need to do this
only _once_.  And never again.

> and it assumes that there is no AC_CONFIG_SUBDIRS.

Why? This is trivial to check, too.  Oh, you mean you would
need several copies of some_snippet.am?  Well, you can adjust
the path for subpackages.  A bit more work, but still not much.

> If something like this is supposed to be run, then it
> should work on the generated Makefile.in files. (That
> would be the job of automake, anyway.) The some_snippet.am
> would have to be converted into some_snippet.in in
> $(top_srcdir), and this would break the $(top_srcdir)
> variable for all Makefiles in subdirectories.

I don't understand this.  Why can't you change Makefile.am
before running automake?  Is it because you are neither the
packages' author nor do you have the tools to modify the
package?

Please clarify the reason for your seemingly unreasonable
constraints.  To me, they make no sense, because here:

> I would like to add recursive targets to extend the test
> framework (e.g. to not stop testing completely if a
> single unittest fails in a subdirectory deep inside), or
> to recursively create a coverage report, to add common
> build targets for the documentation, and so on.

What is the test framework composed of?  Simple Automake TESTS/
check_* stuff, or Autotest, or DejaGNU, or something else?

> My suggestion would be something like this: Some macro in
> configure.ac

You suggest adding stuff to configure.ac.

Why is it that you may adjust configure.ac (and possibly
subpackages' configure.ac files?) but not Makefile.am files?

>       AM_ADD_TARGET([mytarget],[dependencies],
>               some
>               program
>               lines
>               could
>               go here
>       )
> 
> It could be used to create targets "mytarget" and "mytarget-am"
> as for the existing recursive targets, to add mytarget-recursive
> to $(RECURSIVE_TARGETS), to add it to .PHONY, and so on.

I can see the usefulness of something vaguely similar to this,
but I don't see why you need it in the issue you describe.

> Of course this might introduce problems, too (e.g. when using
> recursive targets in the dependencies). It would be necessary
> to document the difference between "install" and "install-am",
> for example.

To summarize: you still have not convinced me, that the problem
you really want to solve is best solved the way you describe.
If you can make the problem space clear, there may be a chance
that someone can suggest a better way to solve it.

Cheers,
Ralf