From: Brian Candler <B.Candler@...>
Date: 2003-03-22T22:45:53+09:00
Subject: Re: Rake problem?

On Sat, Mar 22, 2003 at 10:19:41PM +0900, Jim Weirich wrote:
> If all we are doing with the sub-directory rakefile is record
> dependencies, then there are several ways of handling it.  For example
> 
> (1) Record dependencies in a rakefile in each subdirectory and
> recursively include them.
> (2) Calculate and append the dependencies to a master Rakefile.
> (3) Calculate and store the dependencies in a single file, but separate
> from the master Rakefile.
> (4) Recalculate the dependencies dynamically each time Rake is invoked.
> (5) Calculate and store the dependencies in a serialized format (e.g.
> using Marshall or PStore).

When you say 'calculate dependencies' do you mean like 'make depend' - i.e.
running the source code through the preprocessor to determine which
additional files it uses?

I was just thinking about explicit (hand-written) rules. If you have a
subdirectory with certain source files in it, then to me it makes sense to
include the build rules within that directory - especially if that directory
ends up getting grafted into a different project. I don't think it should be
much less efficient than having a central file.

As for 'make depend'-type dependencies: fixing that would be a big bonus.
ISTM that whenever you compile foo.c to foo.o, that is the right time also
to determine (and store) the automatic dependencies. gcc -M or -MD gives you
output in Makefile format of course, so it still needs to be parsed - but
sticking it into a serialised object seems a very good way to make it
persist (whether that be one per directory, or one per project)

Doing it this way would mean never having to do a 'make depend'!

Regards,

Brian.