diff --git a/src/asm/Makefile b/src/asm/Makefile
new file mode 100644
index 00000000..9957c2ca
--- /dev/null
+++ b/src/asm/Makefile
@@ -0,0 +1,13 @@
+all: rgbasm
+
+asmy.y: yaccprt1.y gameboy/yaccprt2.y yaccprt3.y gameboy/yaccprt4.y
+	cat $^ > $@
+
+.y.c:
+	bison -d -o $@ $^
+
+.c.o:
+	gcc -Wall -DGAMEBOY -I. -I.. -Iinclude -Igameboy -g -c -o $@ $<
+
+rgbasm: $(patsubst %.c,%.o,$(wildcard *.c) $(wildcard gameboy/*.c))
+	gcc -Wall -o $@ $^ -lm
diff --git a/src/asm/include/output.h b/src/asm/include/output.h
index 17b3519a..c96c43aa 100644
--- a/src/asm/include/output.h
+++ b/src/asm/include/output.h
@@ -1,6 +1,7 @@
 #ifndef OUTPUT_H
 #define OUTPUT_H 1
 
+#include	"rpn.h"
 #include	"types.h"
 
 struct Section
@@ -32,4 +33,4 @@ void out_RelLong (struct Expression *expr);
 void	out_PushSection( void );
 void	out_PopSection( void );
 
-#endif
\ No newline at end of file
+#endif