Re: Target depending variables?

[Stefano Lattarini]

On 04/01/2012 06:52 PM, Jules Colding wrote:
> Hi,
> 
> I'd like my SUBDIRS variable not to be set when, and only when,
> the target is distclean. I can't seem to find a way to do that
> in my Makefile.am. Is it possible at all?
>
If you can assume GNU make, yes:

  SUBDIRS = foo bar
  distclean-recursive: SUBDIRS =

If you need something that works also with non-GNU make implementations,
you could resort to the following hack (which abuses Automake internal
details):

  distclean-recursive:
  RECURSIVE_CLEAN_TARGETS = \
    mostlyclean-recursive \
    clean-recursive \
    maintainer-clean-recursive

Note that there is no assurance this will continue to work with future
versions of Automake.

HTH,
  Stefano