All implicit rules in notmuch Makefiles are "pattern rules"; Deleting the
default suffixes (to support obsolete, old-fashioned "suffix rules") from
make reduces the output of 'make -d' by 40 to 90 percent, helping e.g.
debugging make problems.
DEPS := $(SRCS:%.c=.deps/%.d)
DEPS := $(DEPS:%.cc=.deps/%.d)
-include $(DEPS)
DEPS := $(SRCS:%.c=.deps/%.d)
DEPS := $(DEPS:%.cc=.deps/%.d)
-include $(DEPS)
+
+.SUFFIXES: # Delete the default suffixes. Old-Fashioned Suffix Rules not used.