diff --git a/board/adder/Makefile b/board/adder/Makefile
index 6b3706d..70205f1 100644
--- a/board/adder/Makefile
+++ b/board/adder/Makefile
@@ -26,7 +26,7 @@
 
 include $(TOPDIR)/config.mk
 
-LIB	= $(obj)lib$(BOARD).a
+LIB	= $(obj)lib$(BOARD).o
 
 COBJS	:= $(BOARD).o
 
@@ -35,7 +35,7 @@
 SOBJS	:= $(addprefix $(obj),$(SOBJS))
 
 $(LIB):	$(obj).depend $(OBJS)
-	$(AR) $(ARFLAGS) $@ $(OBJS)
+	$(call cmd_link_o_target, $(OBJS))
 
 clean:
 	rm -f $(SOBJS) $(OBJS)