Fixed makefile

Fixed the ugly `debug` target that was overwritten with debugger options with the `-g` c flag

src/Makefile

@@ -2,20 +2,23 @@ CC = clang
 LD = clang
 DB = lldb
 
-CFLAGS = -I ../include -g
+CFLAGS_COMMON = -I ../include -Wall -Wextra
+CFLAGS = $(CFLAGS_COMMON)
 
 OBJ = main.o parse.o endian.o write.o
 BUILD = ../build
 
-all: clean jas
+all: clean jas debug
 
+jas: CFLAGS = $(CFLAGS_COMMON)
 jas: $(OBJ)
 	$(LD) $^ -o $(BUILD)/$@ 
 
-# TODO: fix this ugly hack!
-debug: clean jas $(OBJ)
-	 $(DB) $(BUILD)/jas
+debug: CFLAGS = $(CFLAGS_COMMON) -g
+debug: clean $(OBJ)
+	$(LD) $(wordlist 2,$(words $^),$^) -o $(BUILD)/$@ 
+	$(DB) $(BUILD)/debug
 
 clean:
 	rm -r -f *.o $(BUILD)
-	mkdir -p $(BUILD)
+	mkdir -p $(BUILD)