Re: Question about dependencies

[Galen Seitz]

Sam Ravnborg wrote:
> On Thu, Apr 09, 2009 at 06:38:56PM +1000, Gilles Gigan wrote:
> > Hi,
> > i have a question about automatically generating prerequisites as
> > explained in section 4.14 of the make manual:
> > If I understand this section correctly, the .d files must be shipped
> > with the source code and must not be removed by a "clean" target.
> > Otherwise, the next "make" will complain about not being able to
> > include them, even though they will be generated afterwards.
> > Is this correct ?
> >
> > Now, I would like to get around having to ship these files with the
> > source code. Is there a way to have make generate these .d files IFF
> > they are missing, and then include them ?
>
> First off make cannot possibly generate the dependency files,
> you need some tool for that.
>
> The typical way to deeal with generating .d files is to
> generate them in the same command as used to generate .o files.
>
> Then you can do a simple:
>
> ifneq ($(wildcard *.d),)
> include $(wildcard *.d)
> endif
>
> So you do not try to include .d files that does not yet exist.

Another way to do this is to use -include.  This will silently ignore 
any files that don't exist.

-include $(wildcard *.d)

You can find lots of good information on dependency generation here:
http://make.mad-scientist.us/autodep.html

--
Galen Seitz
address@hidden