Restructure and refactor makefiles

- Allow rebuilds without rebuilding everything
 By detecting changes everywhere that matters (flags, objects and headers).
- Add progress bar
- Fully clean everything when clean goal is used

modules/hekate_libsys_minerva/Makefile

@@ -5,12 +5,16 @@ endif
 include $(DEVKITARM)/base_rules
 
 TARGET := libsys_minerva
-BUILD := ../../build/$(TARGET)
-OUTPUT := ../../output
+BUILDDIR := ../../build/$(TARGET)
+OUTPUTDIR := ../../output
 BDKDIR := bdk
 BDKINC := -I../../$(BDKDIR)
 
-OBJS = $(addprefix $(BUILD)/,\
+# Track compiler flags
+TRACK_CFLAGS = $(BUILDDIR)/.cflags
+TRACK_LDFLAGS = $(BUILDDIR)/.ldflags
+
+OBJS = $(addprefix $(BUILDDIR)/,\
 	sys_sdrammtc.o \
 )
 
@@ -18,17 +22,21 @@ ARCH := -march=armv4t -mtune=arm7tdmi -mthumb-interwork
 CFLAGS = $(ARCH) -O2 -nostdlib -fpie -ffunction-sections -fdata-sections -fomit-frame-pointer -std=gnu11 -Wall -Wsign-compare $(CUSTOMDEFINES)
 LDFLAGS = $(ARCH) -fpie -pie -nostartfiles -lgcc
 
-.PHONY: clean all
+.PHONY: all
 
 all: $(TARGET).bso
-$(BUILD)/%.o: ./%.c
-	@mkdir -p "$(BUILD)"
-	@$(CC) $(CFLAGS) $(BDKINC) -c $< -o $@
+$(BUILDDIR)/%.o: ./%.c $(TRACK_CFLAGS)
+	@mkdir -p "$(BUILDDIR)"
+	@$(CC) $(CFLAGS) $(BDKINC) -MMD -MP -c $< -o $@
 
-$(TARGET).bso: $(OBJS)
-	@$(CC) $(LDFLAGS) -e minerva_entry $^ -o $(OUTPUT)/$(TARGET).bso
-	@$(STRIP) -g $(OUTPUT)/$(TARGET).bso
-	@echo  -e "-------------\nBuilt module: "$(TARGET)".bso\n-------------"
+$(TARGET).bso: $(OBJS) $(TRACK_LDFLAGS)
+	@$(CC) $(LDFLAGS) -e minerva_entry $(OBJS) -o $(OUTPUTDIR)/$(TARGET).bso
+	@$(STRIP) -g $(OUTPUTDIR)/$(TARGET).bso
+	@echo "Built module: "$(TARGET)".bso"
 
-clean:
-	@rm -rf $(OUTPUT)/$(TARGET).bso
+# Non objects change detectors.
+$(TRACK_CFLAGS): $(BUILDDIR)
+	@echo '$(CFLAGS)' | cmp -s - $@ || echo '$(CFLAGS)' > $@
+$(TRACK_LDFLAGS): $(BUILDDIR)
+	@echo '$(LDFLAGS)' | cmp -s - $@ || echo '$(LDFLAGS)' > $@
+-include $(OBJS:.o=.d)