diff --git a/screen/Makefile b/screen/Makefile
index 932bc13..3ecdb30 100644
--- a/screen/Makefile
+++ b/screen/Makefile
@@ -5,7 +5,7 @@ MACFLAGS+=-i../include
 
 SRCC=a_1_buf.c a_2_buf.c a_z_buf.c n_screen.c s_1_buf.c scr2spr.c
 SRCS=cl_screen.s cl_z_screen.s
-SRCS=f_screen.s f_z_screen.s
+SRCS+=f_screen.s f_z_screen.s
 SRCS+=p_pixel.s p_pixels.s
 SRCS+=hline.s vline.s line.s
 SRCS+=scr_copy.s scr_rotate.s