add subdirs

Makefile

@@ -69,6 +69,7 @@ FIX := tools/gbafix/gbafix
 # Secondary expansion is required for dependency variables in object rules.
 .SECONDEXPANSION:
 
+
 $(shell mkdir -p $(C_BUILDDIR) $(ASM_BUILDDIR) $(DATA_ASM_BUILDDIR) $(SONG_BUILDDIR) $(MID_BUILDDIR))
 
 infoshell = $(foreach line, $(shell $1 | sed "s/ /__SPACE__/g"), $(info $(subst __SPACE__, ,$(line))))
@@ -101,6 +102,10 @@ MID_OBJS := $(patsubst $(MID_SUBDIR)/%.mid,$(MID_BUILDDIR)/%.o,$(MID_SRCS))
 OBJS := $(C_OBJS) $(ASM_OBJS) $(DATA_ASM_OBJS) $(SONG_OBJS) $(MID_OBJS)
 OBJS_REL := $(patsubst $(OBJ_DIR)/%,%,$(OBJS))
 
+SUBDIRS  := $(sort $(dir $(OBJS)))
+
+$(shell mkdir -p $(SUBDIRS))
+
 TOOLDIRS := $(filter-out tools/agbcc tools/binutils,$(wildcard tools/*))
 TOOLBASE = $(TOOLDIRS:tools/%=%)
 TOOLS = $(foreach tool,$(TOOLBASE),tools/$(tool)/$(tool)$(EXE))