+ @for d in $(CONTRIB_SUBDIRS); do (cd $$d && $(MAKE) clean); done
+
+install:
+ @for d in $(CONTRIB_SUBDIRS); do (cd $$d && $(MAKE) install); done
+
+uninstall:
+ @for d in $(CONTRIB_SUBDIRS); do (cd $$d && $(MAKE) uninstall); done
+
+.PHONY: all clean install uninstall