Generic Makefile honoring 'Why recursive make is harmful' http://aegis.sourceforge.net/auug97.pdf

depend.sh

#!/bin/sh --posix
SRC="$1"
DIR=`dirname $SRC`
SUFFIX=o.mk

shift 1
# append dependency information
RULE=`cc -MM -MG "$@"`
#OBJ=`echo "$RULE" | cut -d':' -f 1`
SRC=`echo "$RULE" | cut -d':' -f 2`

cat <<EOF
${DIR}/${RULE}

SRC += ${SRC}
EOF

Makefile

-include Settings.mk

# [ project ]
# ===========
default: all

# [ settings ]
# ============
BASE_DIR := $(realpath $(PWD))

BUILD_DIR := $(BASE_DIR)/build
OS := $(shell uname -s)
GCOV_TOOL ?= gcov
CFLAGS += -I$(INCLUDE_DIR)

# use this in modules to reference to the included modules.mk
DIR = $(realpath $(patsubst %/,%,$(dir $(lastword $(MAKEFILE_LIST)))))

# each module may append to this
OBJS :=
SRC :=
PROGRAMS :=
TESTS :=

# include the description for each module
-include module.mk
include $(patsubst %,%/module.mk,$(MODULES))

# look for include files in each of the modules
# use -isystem ?
CFLAGS += $(patsubst %,-I%,$(MODULES))

all: $(OBJS) $(PROGRAMS) $(TESTS)

# [ os ]
# ======

ifeq ($(DEBUG), true)
ifeq ($(OS),Darwin)
CFLAGS += -gdwarf-2 -g -O0 -fno-inline
endif
ifeq ($(OS),Linux)
CFLAGS += -g -O0 -fno-inline
endif
endif


# [ build ]
# =========
define PROGRAM_template
$(1): $$($(2)_OBJS) $(1).c
	$$(CC) $$(CFLAGS) $$($(2)_CFLAGS) $$(LDFLAGS) $$($(2)_LDFLAGS) \
	-o $(1) $$($(2)_OBJS)

OBJS += $$($(2)_OBJS)
endef
$(foreach prog,$(PROGRAMS),$(eval $(call PROGRAM_template,$(prog),$(notdir $(prog)))))

define TEST_template
$(1): $$($(2)_OBJS) $(1).c
	$$(CC) $$(CFLAGS) $$($(2)_CFLAGS) $$(LDFLAGS) $$($(2)_LDFLAGS) \
	-o $(1) $$($(2)_OBJS) && $(1)

OBJS += $$($(2)_OBJS)
endef
$(foreach prog,$(TESTS),$(eval $(call TEST_template,$(prog),$(notdir $(prog)))))


# [ headers ]
# ===========
# calculate C include dependencies
%.o.mk: %.c
	$(BASE_DIR)/depend.sh $*.c $(CFLAGS) $*.c > $@
	
# include the C include dependencies
include $(OBJS:=.mk)
	

# [ uncrustify ]
# ==============
.uncrustify: $(SRC)
	uncrustify --mtime -c $(BASE_DIR)/uncrustify.cfg --replace $? &&\
	touch .uncrustify
	
uncrustify: .uncrustify;
	
	
# [ ragel ]
# ===========
# object generation rules
.PRECIOUS: %.c
%.c: %.rl
	ragel -L -G2 -o $@ $<	

%.dot: %.rl
	ragel -V -p -o $@ $<

%.png: %.dot
	dot -Tpng $< -o $@


# [ gcov/lcov ]
# =============
LCOV_INFO_FILE := coverage.info
LCOV_DIR := coverage

$(LCOV_DIR)/index.html: $(LCOV_INFO_FILE)
	genhtml --ignore-errors source $(LCOV_INFO_FILE) \
	--output-directory $(LCOV_DIR)

$(LCOV_INFO_FILE): $(TESTS)
	lcov --capture --directory $(BASE_DIR) \
	--no-external --output-file $(LCOV_INFO_FILE) \
	--gcov-tool $(GCOV_TOOL)
	
coverage: $(LCOV_DIR)/index.html;


# [ clean ]
# =========
# contains only existing artifacts
ARTIFACTS := $(OBJS) $(OBJS:=.mk) \
	$(OBJS:.o=.gcda) $(OBJS:.o=.gcno) \
	$(LCOV_DIR) $(LCOV_INFO_FILE)

clean: 
	rm -rf $(ARTIFACTS)
	
-include Rules.mk