Added automatic dependency generation to makefile

makefile

@@ -1,9 +1,8 @@
+TARGET = rx
 MCU = attiny85
 F_CPU = 16000000
-RM = rm -rf
-MKDIR = mkdir -p
 EXTRAINCDIR = include
-CSTANDARD = gnu99
+CSTANDARD = c99
 BUILDDIR = build
 
 GCC = avr-gcc
@@ -11,6 +10,8 @@ SIZE = avr-size
 OBJCOPY = avr-objcopy
 OBJDUMP = avr-objdump
 AVRDUDE = avrdude
+RM = rm -rf
+MKDIR = mkdir -p
 
 SRC = src/main.c
 SRC += src/timer.c
@@ -23,27 +24,24 @@ ifeq ($(DEBUG),1)
 	SRC += src/serial.c
 endif
 
-OBJ = $(addprefix $(BUILDDIR)/, $(SRC:.c=.o))
-
 CARGS = -mmcu=$(MCU)
 CARGS += -I$(EXTRAINCDIR)
 CARGS += -Os
-#CARGS += -funsigned-char
-#CARGS += -funsigned-bitfields
-#CARGS += -fpack-struct
-#CARGS += -fshort-enums
-CARGS += -Wall -pedantic -Wstrict-prototypes -Wshadow
-CARGS += -Wpointer-arith -Wcast-qual -Wextra
+CARGS += -funsigned-bitfields
+CARGS += -fpack-struct
+CARGS += -fshort-enums
+CARGS += -ffunction-sections
+CARGS += -Wall -Wextra -pedantic -Werror -Wshadow
+CARGS += -Wpointer-arith -Wcast-qual -Wstrict-prototypes
 CARGS += -Wno-main -Wno-write-strings -Wno-unused-parameter
 CARGS += -std=$(CSTANDARD)
 CARGS += -DF_CPU=$(F_CPU)
-#CARGS += -ffunction-sections
 
 ifeq ($(DEBUG),1)
 	CARGS += -DDEBUG
 endif
 
-#LINKER = -Wl,--relax
+LINKER = -Wl,--relax
 
 #PROGRAMMER = avrisp2
 #ISPPORT = usb
@@ -51,31 +49,46 @@ PROGRAMMER = arduino
 ISPPORT = /dev/tty.usbserial-A100OZQ1
 ISPBAUD = 57600
 
-TARGET = rx
+# -----------------------------------------------------------------------------
 
+OBJ = $(addprefix $(BUILDDIR)/, $(SRC:.c=.o))
+
+.PHONY: all
 all: $(BUILDDIR)/$(TARGET).hex
 
+.PHONY: debug
 debug:
 	$(MAKE) BUILDDIR=build/debug TARGET=debug MCU=atmega328 DEBUG=1 all
 
+.PHONY: debugProgram
+debugProgram:
+	$(MAKE) BUILDDIR=build/debug TARGET=debug MCU=atmega328p DEBUG=1 program
+
+.PHONY: program
+program: $(BUILDDIR)/$(TARGET).hex
+	$(AVRDUDE) -p $(MCU) -c $(PROGRAMMER) -b $(ISPBAUD) -P $(ISPPORT) -e -D -U $(BUILDDIR)/$(TARGET).hex
+
+.PHONY: clean
+clean:
+	$(RM) $(BUILDDIR)
+
+-include $(OBJ:.o=.d)
+
 $(BUILDDIR)/%.o: %.c
 	@$(MKDIR) $(BUILDDIR)/$(dir $<)
-	$(GCC) -c $< -o $@ $(CARGS)
+	$(GCC) $(CARGS) -c $< -o $@
+	@$(GCC) $(CARGS) -MM $*.c > $(BUILDDIR)/$*.d
+	@mv -f $(BUILDDIR)/$*.d $(BUILDDIR)/$*.d.tmp
+	@sed -e 's|.*:|$(BUILDDIR)/$*.o:|' < $(BUILDDIR)/$*.d.tmp > $(BUILDDIR)/$*.d
+	@sed -e 's/.*://' < $(BUILDDIR)/$*.d.tmp | sed -e 's/\\$$//' | \
+		fmt -1 | sed -e 's/^ *//' | sed -e 's/$$/:/' >> $(BUILDDIR)/$*.d
+	@rm -f $(BUILDDIR)/$*.d.tmp
 
 $(BUILDDIR)/$(TARGET).elf: $(OBJ)
-	$(GCC) $(CARGS) $(OBJ) --output $@ $(LINKER) -Wl,-Map -Wl,$(@:.elf=.map)
+	$(GCC) $(CARGS) $(OBJ) $(LINKER) -Wl,-Map -Wl,$(@:.elf=.map) --output $@
 	$(SIZE) $@
 
 $(BUILDDIR)/$(TARGET).hex: $(BUILDDIR)/$(TARGET).elf
 	$(OBJCOPY) -O ihex $< $@
 	$(OBJDUMP) -h -S $< > $(@:.hex=.lss)
 
-program: $(BUILDDIR)/$(TARGET).hex
-	$(AVRDUDE) -p $(MCU) -c $(PROGRAMMER) -b $(ISPBAUD) -P $(ISPPORT) -e -D -U $(BUILDDIR)/$(TARGET).hex
-
-debugProgram:
-	$(MAKE) BUILDDIR=build/debug TARGET=debug MCU=atmega328p DEBUG=1 program
-
-clean:
-	$(RM) $(BUILDDIR)
-