share/mk/dirdeps.mk

37 # This is what we do with DIRDEPS
56 #	Also, for each fully qualified directory target, we will search
62 #	Before each Makefile.depend file is read, we set
112 #		# make sure we know what TARGET_SPEC is
113 #		# as we may need it to find Makefile.depend*
124 #		If ALL_MACHINES is defined, we build for all the
176 # the first time we are included the _DIRDEP_USE target will not be defined
177 # we can use this as a clue to do initialization and other one time things.
180 # do some setup we only need once
205 # make sure we get the behavior we expect
215 # we allow for this to be a subset
218 # this is what we started with
220 # this is what we mostly use below
223 # make sure we have defaults
230 # In order to stay sane, we need to ensure that all the build_dirs
231 # we compute below are fully qualified wrt DEP_TARGET_SPEC.
233 # so we need to construct a set of modifiers to fill in the gaps.
281 # for machine specific dependfiles we require ${MACHINE} to be at the end
282 # also for the sake of sanity we require a common prefix
296 # this is how we identify non-machine specific dependfiles
299 # this gets reset for each dirdep we check
302 # remember the initial value of DEP_RELDIR - we test for it below.
326 # First off, we want to know what ${MACHINE} to build for.
327 # This can be complicated if we are using a mixture of ${MACHINE} specific
330 # if we were included recursively _DEP_TARGET_SPEC should be valid.
335 # record that we've read dependfile for this
342 # we need to parse DEP_MACHINE may or may not contain more info
362 # we can avoid the overhead of re-computing the tree dependencies.
368 # this is where we will cache all our work
383 # things we skip for host tools
388 # things we always skip
415 # this is what we run below
418 # we normally want the default target
428 # when we want to report.
435 # we suppress SUBDIR when visiting the leaves
436 # we assume sys.mk will set MACHINE_ARCH
438 # if there is no makefile in the target directory, we skip it.
453 # we start with everything
456 # some things we know we want to ignore
466 # first trim things we know we want to skip
509 # we must be boot-strapping
521 # if ONLY_TARGET_SPEC_LIST or ONLY_MACHINE_LIST is set, we are limited to that.
535 # we must first qualify
548 # make sure we have a starting place?
562 # we do this via sub-make
590 # we need the .meta file to ensure we update if
614 # we want to capture the dirdeps count in the cache
630 # the rest is done repeatedly for every Makefile.depend we read.
631 # if we are anything but the original dir we care only about the
632 # machine type we were included for..
649 # this is the machine list we actually use below
653 # we need to build this guy's dependencies for host as well.
665 # we need to tweak _machines
667 # apply the same filtering that we do when qualifying DIRDEPS.
669 # Again we expect that any already qualified machines are fully qualified.
690 # these we reset each time through as they can depend on DEP_MACHINE
700 # this is what we start with
704 # we can tell the unqualified ones easily - because they exist
709 # if it was called out - we likely need it.
722 # _build_dirs is what we will feed to _DIRDEP_USE
733 # make sure we do not mess with qualifying "host" entries
747 # we do not want to waste time chasing DIRDEPS
748 # but if we want to count the number of Makefile.depend* read, we do.
752 # we use _cache_script to minimize the number of times we fork the shell
818 # we do not have the same limits on command lines
846 # we pass _DEP_TARGET_SPEC to tell the next step what we want
869 # we can skip :tA since we computed the path above
878 # set these as if we found Makefile.depend*
896 # we are building something
899 # Since we are/should be included by .MAKE.DEPENDFILE
939 # if we are bootstrapping create the default