Hi, as a test I changed the depend generation to main nuttx Makefiles to this:
%.dd: %.c $(Q) $(MKDEP) $(DEPPATH) "$(CC)" -- $(CFLAGS) -- $< > $@ makedepfile: $(patsubst %.c,%.dd,$(SRCS)) @for f in $^; do cat $$f; done > Make.dep $(call DELFILE, $^) .depend: Makefile $(SRCS) $(TOPDIR)$(DELIM).config $(Q) $(MAKE) makedepfile $(Q) touch $@ This allows to parallelize each MKDEP call, which currently is done once with all $(SRCS) together. Original: make depend -j8 11.29s user 6.67s system 106% cpu 16.888 total Parallel: make depend -j8 14.34s user 5.73s system 286% cpu 6.994 total So about 10 seconds less and much more CPU utilized. What do you think of the change? Any reason not to do this? Best, Matias
