Re: [Chicken-hackers] Re: separate build directory support for Chicken

[Peter Bex]

On Sun, Jan 13, 2008 at 11:26:30AM +0600, Ivan Shmakov wrote:
>       And, well, I have some trouble understanding the manageability
>       or even readability of the Makefile fragments like the
>       following:
> 
> --cut--
> FOO-1$(O): FOO-1.c
>       COMPILE-IT
> FOO-2$(O): FOO-2.c
>       COMPILE-IT
> [ ... 74 lines skipped... ]
> FOO-40$(O): FOO-40.c
>       COMPILE-IT
> --cut--
> 
>       Rather, I'd have:
> 
> --cut--
> FOO_SOURCES = FOO-1.c FOO-2.c ... FOO-40.c
> FOO_OBJECTS = $(FOO_SOURCES:.c=$(O))
> 
> $(FOO_OBJECTS) : %$(O) : %.c
>       COMPILE-IT
> --cut--

With pmake (BSD makefiles), this can be done in an elegant way as well
and without the horrible resulting Makefile.in/configure/Makefile mess
that you get with autofools:

--cut--
PROG=foo
SRCS=foo-1.c foo-2.c foo-3.c ... foo-40.c

.include <bsd.prog.mk>
--cut--

That's it, and that's all you need.  No messing about with autohell
versions, no undecipherable configure scripts or Makefile.in files.
Instead of generating a huge standalone build environment with the info
you need to build the program in it, the BSD make system puts this in
a system-wide directory, so your program does not need to carry it.
Politically this might be hard to implement, in this brave GNU world
(I wouldn't care, though).

>       Would there be more dependencies for FOO-N objects, I'd add them
>       as follows:
> 
> $(FOO_OBJECTS)          : GENERIC-FOO-DEPENDENCIES
> FOO-X$(O) FOO-Y$(O)     : SPECIFIC-FOO-X-Y-DEPENDENCIES
> FOO-Z$(O)               : SPECIFIC-FOO-Z-DEPENDENCIES

You can add to the default rules generated by pmake too, like you
would with any regular make script:

foo.c: foo-something.h

>       Furthermore, I'd suggest using the C compiler to compute
>       dependencies, and not to hardcode them in the makefile.

You can use mkdep(1) for that, which calls the C compiler and outputs
a nice file that pmake can use.  Of course pmake comes with default
targets to generate this file automatically.

However, having said all this, I don't think the current Makefile
system is all that complicated.  It's pretty redundant but that does
not have to be a problem.

Cheers,
Peter
-- 
http://sjamaan.ath.cx
--
"The process of preparing programs for a digital computer
 is especially attractive, not only because it can be economically
 and scientifically rewarding, but also because it can be an aesthetic
 experience much like composing poetry or music."
                                                        -- Donald Knuth

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