Using Makefile to clean subdirectories

Question

Is it possible to perform a make clean from the parent directory which also recursively cleans all sub-directories without having to include a makefile in each sub-directory?

For example, currently in my Makefile, I have something like:

SUBDIRS = src, src1

.PHONY: clean subdirs $(SUBDIRS)

clean: $(SUBDIRS)
    rm -rf *.o *~ core .depend .*.cmd *.ko *.mod.c

$(SUBDIRS):
    $(MAKE) -C $(SUBDIRS) clean 

However, this requires me to have a Makefile in both src and src1. Otherwise, I would get the error

No rule to make target clean

Since I only want to run the command "rm -rf *.o ~ core .depend ..cmd *.ko *.mod.c" in each subdirectory anyways, it seems redundant to have to include a Makefile in every subdirectory with the exact same line for clean. Is there no way to simply have the same clean command run in each of the subdirectories?

Answer 1

I agree that you could just have the rm command operate on subdirs. But something like the following allows recursive make using only a single makefile:

SUBDIRS = . src src1
SUBDIRSCLEAN=$(addsuffix clean,$(SUBDIRS))

clean: $(SUBDIRSCLEAN)

clean_curdir:
    rm -rfv *.o *~ core .depend .*.cmd *.ko *.mod.c

%clean: %
    $(MAKE) -C $< -f $(PWD)/Makefile clean_curdir