diff --git a/make/defs-orig.mk b/make/defs-orig.mk
index 96ca297a..d89b378f 100644
--- a/make/defs-orig.mk
+++ b/make/defs-orig.mk
@@ -52,7 +52,7 @@ PREREQ_CPP  = $(foreach dir,$(PREREQ_DIR),$(wildcard $(dir)/*.c)) \
 PREREQ_CSRC = $(PREREQ_H) $(PREREQ_C) $(PREREQ_CPP)
 
 CONTRIB_MOD = $(addprefix contrib/,$(CONTRIB_LIBS))
-REQUIRED   += $(CONTRIB_MOD)
+REQUIRED   := $(CONTRIB_MOD) $(REQUIRED)
 ALL_H       = $(LOCAL_H) $(PREREQ_H)
 ALL_C       = $(LOCAL_C) $(PREREQ_CPP)
 ALL_CPP     = $(LOCAL_CPP) $(PREREQ_CPP)