Re: Recursive make harmful

[Alexandre Duret-Lutz]

>>> "Tom" == Tom Tromey <address@hidden> writes:

[...]

 Tom> The idea would be to read all the Makefile.am
 Tom> at once and then generate a single large Makefile.in.

 Tom> Unfortunately I think this is very hard.  We could
 Tom> probably do it if we could add additional constraints on
 Tom> the Makefile.am writer.  Unfortunately these constraints
 Tom> might be enough of a pain that it would be easier to just
 Tom> write a single Makefile.am in the first place.

There is something nice about having one Makefile.am in each
subdirectory, it's that it helps to make selfcontained and
reusable modules.
Actually I have three projects that share a few directories
(not unlike lib/ and m4/ in Textutils, Fileutils, and Shellutils).
If I do a single Makefile.am at the toplevel of each project
I will want a way to maintain the rules for these directories in
a single place.  One way is to include the set of rules from 
a file shared in these directories.

If one of the shared directory is foo/, I'll probably have
this in foo/rules.am:

   bin_PROGRAMS = foo/foo
   foo_SOURCES = foo/foo.c foo/bar.c foo/foo.h foo/bar.h

and the following in the toplevel Makefile.am:

   include $(top_srcdir)/foo/rules.am

I beleive this should work (BTW, I hope I'm allowed to have several
assignements to bin_PROGRAMS in the same file).  

But now one of the three project has the foo/ directory in
another directory.  Let's say it's bar/foo/ (or I could have
renamed foo/ into mumble/ it the same problem).  Using

   include $(top_srcdir)/bar/foo/rules.am

will not works because the rules in rules.am explicitely use
foo/ and not bar/foo/.

I think that one solution would be to use something like
this in foo/rules.am:

   bin_PROGRAMS = $(foo_LOCATION)/foo
   foo_SOURCES = $(foo_LOCATION)/foo.c $(foo_LOCATION)/bar.c 
$(foo_LOCATION)/foo.h $(foo_LOCATION)/bar.h

and the following in the toplevel Makefile.am:

   foo_LOCATION=bar/foo
   include $(top_srcdir)/bar/foo/rules.am

But that's really painful.  Does s.o. has another idea?  (I'm
thinking that maybe automake could figure `bar/foo' from the
include path, and do something helpful with that...).
-- 
Alexandre Duret-Lutz