Makefile: Fix lpc176x and stm32f1 builds

Commit e18501d0 broke the build for targets that added objects to
klipper.elf via adding dependencies.  Rework the build so that it is
possible to add objects to klipper.elf via a new OBJS_klipper.elf
makefile variable.

Signed-off-by: Kevin O'Connor <kevin@koconnor.net>

Makefile

@@ -37,6 +37,8 @@ CFLAGS := -I$(OUT) -Isrc -I$(OUT)board-generic/ -std=gnu11 -O2 -MD -g \
     -ffunction-sections -fdata-sections
 CFLAGS += -flto -fwhole-program -fno-use-linker-plugin
 
+OBJS_klipper.elf = $(patsubst %.c, $(OUT)src/%.o,$(src-y))
+OBJS_klipper.elf += $(OUT)compile_time_request.o
 CFLAGS_klipper.elf = $(CFLAGS) -Wl,--gc-sections
 
 CPPFLAGS = -I$(OUT) -P -MD -MT $@
@@ -83,9 +85,9 @@ $(OUT)compile_time_request.o: $(patsubst %.c, $(OUT)src/%.o.ctr,$(src-y)) ./scri
 	$(Q)$(PYTHON) ./scripts/buildcommands.py -d $(OUT)klipper.dict -t "$(CC);$(AS);$(LD);$(OBJCOPY);$(OBJDUMP);$(STRIP)" $(OUT)klipper.compile_time_request $(OUT)compile_time_request.c
 	$(Q)$(CC) $(CFLAGS) -c $(OUT)compile_time_request.c -o $@
 
-$(OUT)klipper.elf: $(patsubst %.c, $(OUT)src/%.o,$(src-y)) $(OUT)compile_time_request.o
+$(OUT)klipper.elf: $(OBJS_klipper.elf)
 	@echo "  Linking $@"
-	$(Q)$(CC) $(patsubst %.c, $(OUT)src/%.o,$(src-y)) $(OUT)compile_time_request.o $(CFLAGS_klipper.elf) -o $@
+	$(Q)$(CC) $(OBJS_klipper.elf) $(CFLAGS_klipper.elf) -o $@
 	$(Q)scripts/check-gcc.sh $@ $(OUT)compile_time_request.o
 
 ################ Kconfig rules

src/lpc176x/Makefile

@@ -9,9 +9,6 @@ dirs-y += lib/lpc176x/device/TOOLCHAIN_GCC_ARM
 CFLAGS += -mthumb -mcpu=cortex-m3
 CFLAGS += -Ilib/lpc176x/device -Ilib/cmsis-core
 
-CFLAGS_klipper.elf += -T $(OUT)LPC1768.ld
-CFLAGS_klipper.elf += --specs=nano.specs --specs=nosys.specs
-
 # Add source files
 src-y += lpc176x/main.c lpc176x/gpio.c
 src-$(CONFIG_HAVE_GPIO_ADC) += lpc176x/adc.c
@@ -23,21 +20,23 @@ src-y += ../lib/lpc176x/device/system_LPC17xx.c
 src-$(CONFIG_USBSERIAL) += lpc176x/usbserial.c generic/usb_cdc.c
 src-$(CONFIG_SERIAL) += lpc176x/serial.c generic/serial_irq.c
 
-# Add the TOOLCHAIN_GCC_ARM files to the build
+# Add assembler build rules
 $(OUT)%.o: %.S
 	@echo "  Assembling $@"
 	$(Q)$(AS) $< -o $@
 
 asmsrc-y := ../lib/lpc176x/device/TOOLCHAIN_GCC_ARM/startup_LPC17xx.S
+OBJS_klipper.elf += $(patsubst %.S, $(OUT)src/%.o,$(asmsrc-y))
 
-$(OUT)klipper.elf: $(patsubst %.S, $(OUT)src/%.o,$(asmsrc-y))
+# Build the linker script
-
-target-y := $(OUT)LPC1768.ld $(target-y)
-
 $(OUT)LPC1768.ld: lib/lpc176x/device/TOOLCHAIN_GCC_ARM/LPC1768.ld $(OUT)board-link
 	@echo "  Preprocessing $@"
 	$(Q)$(CPP) -P -MD -MT $@ -DMBED_APP_START=$(CONFIG_FLASH_START) -DMBED_APP_SIZE="(512K - $(CONFIG_FLASH_START))" $< -o $@
 
+CFLAGS_klipper.elf += -T $(OUT)LPC1768.ld
+CFLAGS_klipper.elf += --specs=nano.specs --specs=nosys.specs
+$(OUT)klipper.elf : $(OUT)LPC1768.ld
+
 # Build the additional bin output file
 target-y += $(OUT)klipper.bin
 

src/stm32f1/Makefile

@@ -12,9 +12,6 @@ CFLAGS += -Ilib/cmsis-core
 CFLAGS += -Ilib/cmsis-stm32f1/include -Ilib/hal-stm32f1/include
 CFLAGS += -DSTM32F103xB
 
-CFLAGS_klipper.elf += -T $(OUT)stm32f1.ld
-CFLAGS_klipper.elf += --specs=nano.specs --specs=nosys.specs
-
 # Add source files
 src-y += stm32f1/main.c stm32f1/gpio.c
 src-$(CONFIG_HAVE_GPIO_ADC) += stm32f1/adc.c
@@ -24,22 +21,24 @@ src-y += generic/crc16_ccitt.c generic/armcm_irq.c generic/armcm_timer.c
 src-y += ../lib/cmsis-stm32f1/source/system_stm32f1xx.c
 src-$(CONFIG_USBSERIAL) += stm32f1/usbserial.c generic/usb_cdc.c
 src-$(CONFIG_SERIAL) += stm32f1/serial.c generic/serial_irq.c
-asmsrc-y = ../lib/cmsis-stm32f1/source/startup_stm32f103xb.s
 
 # Add assembler build rules
 $(OUT)%.o: %.s $(OUT)autoconf.h $(OUT)board-link
 	@echo "  Assembling $@"
 	$(Q)$(AS) $< -o $@
 
-$(OUT)klipper.elf: $(patsubst %.s, $(OUT)src/%.o,$(asmsrc-y))
+asmsrc-y = ../lib/cmsis-stm32f1/source/startup_stm32f103xb.s
+OBJS_klipper.elf += $(patsubst %.s, $(OUT)src/%.o,$(asmsrc-y))
 
 # Build the linker script
-target-y := $(OUT)stm32f1.ld $(target-y)
-
 $(OUT)stm32f1.ld: src/stm32f1/stm32f1.ld $(OUT)board-link
 	@echo "  Preprocessing $@"
 	$(Q)$(CPP) -P -MD -MT $@ -DFLASH_START=$(CONFIG_FLASH_START) $< -o $@
 
+CFLAGS_klipper.elf += -T $(OUT)stm32f1.ld
+CFLAGS_klipper.elf += --specs=nano.specs --specs=nosys.specs
+$(OUT)klipper.elf : $(OUT)stm32f1.ld
+
 # Binary output file rules
 target-y += $(OUT)klipper.bin