CROSS_COMPILE ?=

TARGET_FILE ?= bootloader

CXXFLAGS += -O0
CXXFLAGS += -ggdb3
CXXFLAGS += -std=c++17
CXXFLAGS += -pedantic
CXXFLAGS += -pedantic-errors
CXXFLAGS += -ffunction-sections -fdata-sections
CXXFLAGS += -fno-implicit-inline-templates
CXXFLAGS += -Isrc
CXXFLAGS += -std=c++20


LD_LIBS := -lc -lgcc -lpthread

CC = $(CROSS_COMPILE)gcc
CXX = $(CROSS_COMPILE)g++

OBJ_DIR := obj
BIN_DIR := bin
SRC_DIR := src

CC_SRCS = $(wildcard $(SRC_DIR)/*.cc)

CC_OBJS = $(patsubst %.cc,$(OBJ_DIR)/%.o,$(notdir $(CC_SRCS)))

OBJS = $(CC_OBJS)
TARGET = $(BIN_DIR)/$(TARGET_FILE)


.PHONY: all
all: $(TARGET)

$(TARGET): $(OBJS) Makefile
	@mkdir -p $(BIN_DIR)
	$(CXX) $(LD_FLAGS) $(OBJS) $(LD_LIBS) -o $@

$(OBJ_DIR)/%.o: $(SRC_DIR)/%.cc
	@mkdir -p $(dir $@)
	@$(call makedep,$<,$@,$(patsubst %.cc,%.d,$(OBJ_DIR)/$(notdir $<)),$(CXXFLAGS))
	$(CXX) -c $(CXXFLAGS) -o $@ $<

.PHONY: clean
clean:
	rm -rf \
	$(OBJS) \
	$(patsubst %.o,%.d,$(OBJS)) \
	$(TARGET)

define makedep
	$(CXX) -MM -MF $3 -MP -MT $2 $4 $1
endef

ifneq ($(MAKECMDGOALS),clean)
-include $(subst .o,.d,$(OBJS))
endif