diff --git a/Makefile.common b/Makefile.common
new file mode 100644
index 0000000..e65879e
--- /dev/null
+++ b/Makefile.common
@@ -0,0 +1,5 @@
+INCFLAGS := -I$(CORE_DIR)/drivers/libretro -I$(CORE_DIR) -I$(CORE_DIR)/input -I$(CORE_DIR)/boards -I$(CORE_DIR)/mappers
+
+FCEU_SRC_DIRS := $(CORE_DIR)/boards $(CORE_DIR)/input $(CORE_DIR)/mappers
+SOURCES_C := $(foreach dir,$(FCEU_SRC_DIRS),$(wildcard $(dir)/*.c))
+SOURCES_C += $(CORE_DIR)/drivers/libretro/griffin.c $(CORE_DIR)/ines.c $(CORE_DIR)/unif.c $(CORE_DIR)/x6502.c
diff --git a/Makefile.libretro b/Makefile.libretro
index f160408..caf851b 100644
--- a/Makefile.libretro
+++ b/Makefile.libretro
@@ -173,17 +173,13 @@ ifeq ($(EXTERNAL_ZLIB), 1)
 	CFLAGS += -DHAVE_EXTERNAL_ZLIB
 endif
 
-LIBRETRO_DIR := ./src/drivers/libretro
-FCEU_DIR := ./src
+CORE_DIR := src
+
+include Makefile.common
 
 CFLAGS += -DWANT_GRIFFIN
-FCEU_SRC_DIRS := $(FCEU_DIR)/boards $(FCEU_DIR)/input $(FCEU_DIR)/mappers
-FCEU_CSRCS := $(foreach dir,$(FCEU_SRC_DIRS),$(wildcard $(dir)/*.c))
-FCEU_CSRCS += $(LIBRETRO_DIR)/griffin.c $(FCEU_DIR)/ines.c $(FCEU_DIR)/unif.c $(FCEU_DIR)/x6502.c
 
-FCEU_COBJ := $(FCEU_CSRCS:.c=.o)
-
-OBJS := $(FCEU_COBJ)
+OBJECTS := $(SOURCES_C:.c=.o)
 
 FCEU_DEFINES := -D__LIBRETRO__ -DSOUND_QUALITY=0 -DPATH_MAX=1024 -DINLINE=inline -DPSS_STYLE=1 -DFCEU_VERSION_NUMERIC=9813 -DFRONTEND_SUPPORTS_RGB565 $(PLATFORM_DEFINES)
 
@@ -196,30 +192,29 @@ endif
 CFLAGS += $(CODE_DEFINES) $(fpic) $(WARNING_DEFINES) $(FCEU_DEFINES) $(ENDIANNESS_DEFINES)
 LDFLAGS += -lm
 
-INCDIRS := -I$(LIBRETRO_DIR) -I$(FCEU_DIR) -I$(FCEU_DIR)/input -I$(FCEU_DIR)/boards -I$(FCEU_DIR)/mappers
 LIBS :=
 
 ifeq ($(platform), psp1)
-	INCDIRS += -I$(shell psp-config --pspsdk-path)/include
+	INCFLAGS += -I$(shell psp-config --pspsdk-path)/include
 endif
 
 all: $(TARGET)
 
-$(TARGET): $(OBJS)
+$(TARGET): $(OBJECTS)
 ifeq ($(STATIC_LINKING), 1)
-	$(AR) rcs $@ $(OBJS)
+	$(AR) rcs $@ $(OBJECTS)
 else
-	$(CC) -o $@ $(SHARED) $(OBJS) $(CFLAGS) $(LDFLAGS) $(LIBS)
+	$(CC) -o $@ $(SHARED) $(OBJECTS) $(CFLAGS) $(LDFLAGS) $(LIBS)
 endif
 
 %.o: %.c
-	$(CC) -c -o $@ $< $(CFLAGS) $(INCDIRS)
+	$(CC) -c -o $@ $< $(CFLAGS) $(INCFLAGS)
 
 clean-objs:
-	rm -f $(OBJS)
+	rm -f $(OBJECTS)
 
 clean:
-	rm -f $(OBJS)
+	rm -f $(OBJECTS)
 	rm -f $(TARGET)
 
 .PHONY: clean clean-objs
diff --git a/src/drivers/libretro/jni/Android.mk b/src/drivers/libretro/jni/Android.mk
index 7af373f..62c2bc9 100644
--- a/src/drivers/libretro/jni/Android.mk
+++ b/src/drivers/libretro/jni/Android.mk
@@ -15,17 +15,15 @@ ifeq ($(TARGET_ARCH),mips)
 LOCAL_CFLAGS += -DANDROID_MIPS -D__mips__ -D__MIPSEL__
 endif
 
-FCEU_DIR := ../../..
-LIBRETRO_DIR := ..
+CORE_DIR := ../../..
 
 LOCAL_MODULE    := retro
-FCEU_SRC_DIRS := $(FCEU_DIR)/boards $(FCEU_DIR)/input $(FCEU_DIR)/mappers
 
-FCEU_SRC_FILES := $(foreach dir,$(FCEU_SRC_DIRS),$(wildcard $(dir)/*.c))
+include ../../../../Makefile.common
 
-LOCAL_SRC_FILES  = $(LIBRETRO_DIR)/griffin.c $(FCEU_DIR)/ines.c $(FCEU_DIR)/unif.c $(FCEU_DIR)/x6502.c $(FCEU_SRC_FILES)
+LOCAL_SRC_FILES  = $(SOURCES_C)
 
 LOCAL_CFLAGS += -DWANT_GRIFFIN -DINLINE=inline -DSOUND_QUALITY=0 -DPSS_STYLE=1 -DLSB_FIRST -D__LIBRETRO__ -DHAVE_ASPRINTF -DFCEU_VERSION_NUMERIC=9813 -DFRONTEND_SUPPORTS_RGB565
-LOCAL_C_INCLUDES = $(LOCAL_PATH)/$(FCEU_DIR)
+LOCAL_C_INCLUDES = $(LOCAL_PATH)/$(CORE_DIR)
 
 include $(BUILD_SHARED_LIBRARY)