makefiles/dependency_resolution: add outer loop for DEFAULT_MODULE deps

[fjmolinas]

Contribution description

Some DEFAULT_MODULEs in tree have dependencies of their own. This is
usually done for aliases of init modules, and do not have dependencies
themselves.

This adds the final stage to dependency resolutions where DEFAULT_MODULEs
dependencies MAY be included. These included modules MUST NOT have
dependencies themselves.

This allows for modules to disable DEFAULT_MODULEs during dependencies
resolution independent of the inclusion order.

auto_init and periph_init modules are moved to this outer-loop, allowing
therefore for modules to disable them during the dependency resolution

Testing procedure

Dependencies should not have changed.

Issues/PRs references

Could be used by #17584

[benpicco]

Looks like something broke

[fjmolinas]

@benpicco all green, can I squash? I run the dependency check script in parallel after I squash

[benpicco]

Yes please squash!

[benpicco]

looks good to me

[fjmolinas]

I ran the save_dependency_debug script, there were some differences, but IMO they are expected, basically in some cases xtimer and ztimer would get select instead of ztimer, this depends on inclusion order for some applications and boils down to the fact that now gnrc_netif_init_devs becomes a MODULE at the end. Although this module does not have explicit dependencies it has some because of wildcards:

ifneq (,$(filter gnrc_netif_%,$(USEMODULE)))
  USEMODULE += gnrc_netif
endif

ifneq (,$(filter gnrc_netif,$(USEMODULE)))
  USEMODULE += netif
  USEMODULE += l2util
  USEMODULE += fmt
  USEMODULE += ztimer_msec
  ...
endif

So with de previous DEFAULT_MODULE inclusion ztimer_msec got included early on and the when conditional xtimer/ztimer dependencies arrived xtimer was not included:

# unless ztimer_xtimer_compat is used, make xtimer use ztimer_usec as backend.
ifneq (,$(filter ztimer_periph_timer,$(USEMODULE)))
  ifneq  (,$(filter xtimer,$(USEMODULE)))
    ifeq (,$(filter ztimer_xtimer_compat,$(USEMODULE)))
      USEMODULE += xtimer_on_ztimer
    endif
  endif
  ifneq (,$(filter evtimer,$(USEMODULE)))
    USEMODULE += evtimer_on_ztimer
  endif
endif

IMO these differences are OK, since they are based in changes in order of inclusions, this will always happen, and simply adding USEMODULE += ztimer_* earlier would solve it for the target application.

If you agree please hit the green button @benpicco

[fjmolinas]

Maybe @maribu or @leandrolanzieri would like to give it the go, since they have looked at build system a lot :)

[benpicco]

auto_init_gnrc_netif is not a DEFAULT_MODULE

[fjmolinas]

Ahh, I thought it was because of the auto_init_ prefix..., I'll remove it from here then..

[fjmolinas]

If you agree please hit the green button @benpicco

@benpicco pointed out the auto_init_gnrc_netif is not a default module, but the analysis still stands, because I had moved the gnrc_netif_% dependency against it to the end.

[fjmolinas]

Thanks @benpicco!