dirs.mk: Now shortcutting already built directories (dirs.done)

make/dirs.mk

@@ -11,32 +11,59 @@ SUBDIRS ?= $(FIND_SUBDIRS)
 
 ifeq ($(SUBDIRS_TO_ITERATE),)
 
-all:
-subdirs:
-clean distclean:
+all install clean distclean:
+
+else
+
+ifeq ($(MAKECMDGOALS),)
+SUBDIR_TARGETS = all
+else
+SUBDIR_TARGETS = $(filter all install clean distclean,$(MAKECMDGOALS))
+endif
+
+all: dirs.done
+subdirs: dirs.done
+clean: dirs.clean
+distclean: dirs.clean dirs.distclean
+
 .DEFAULT:
 install:
 
-else
 .PHONY: $(SUBDIRS_TO_ITERATE)
 
-ifeq ($(MAKECMDGOALS),)
-all:
-	$(make_subdirs)
-endif
+#ifeq ($(MAKECMDGOALS),)
+#all:
+#	$(make_subdirs)
+#	touch dirs.done
+#
+#$(MAKECMDGOALS):
+#	$(make_subdirs_target)
+#	touch dirs.done
 
-$(MAKECMDGOALS):
-	$(make_subdirs_target)
 
-clean: dirs.clean
-distclean: dirs.distclean clean
+define make_dirs
+	set -e; for t in $(SUBDIR_TARGETS); do \
+		for d in $(SUBDIRS) ; do \
+			make -wC $$d $$t ;\
+		done ;\
+	done
+endef
+
+PREREQ_DIRS_DONE = $(foreach p,$(PREREQ),$($(p)_DIR)/dirs.done)
+
+dirs.done: $(wildcard $(BUILD_HDRDIR)) $(PREREQ_DIRS_DONE)
+	$(make_dirs)
+	touch $@
 
 dirs.clean:
+	$(make_dirs)
 	rm -rf $(TEXTCLEAN) $(CLEAN) dist *.done *~ .*.swp *.tmp core *.rep
 
 dirs.distclean:
+	$(make_dirs)
 	rm -rf $(DISTCLEAN)
 
 .DEFAULT:
-	$(make_subdirs_target)
-endif
+	$(make_dirs)
+
+endif # SUBDIRS_TO_ITERATE