diff --git a/core/base_rules.mk b/core/base_rules.mk
index 07ef024675..5c508cd25f 100644
--- a/core/base_rules.mk
+++ b/core/base_rules.mk
@@ -434,8 +434,7 @@ endif
 ###########################################################
 cleantarget := clean-$(LOCAL_MODULE)
 $(cleantarget) : PRIVATE_MODULE := $(LOCAL_MODULE)
-$(cleantarget) : PRIVATE_CLEAN_FILES := \
-    $(PRIVATE_CLEAN_FILES) \
+$(cleantarget) : PRIVATE_CLEAN_FILES += \
     $(LOCAL_BUILT_MODULE) \
     $(LOCAL_INSTALLED_MODULE) \
     $(intermediates)
diff --git a/core/dynamic_binary.mk b/core/dynamic_binary.mk
index 0ca1858b10..6ede57f8d9 100644
--- a/core/dynamic_binary.mk
+++ b/core/dynamic_binary.mk
@@ -128,8 +128,7 @@ endif
 endif # LOCAL_STRIP_MODULE
 
 
-$(cleantarget): PRIVATE_CLEAN_FILES := \
-			$(PRIVATE_CLEAN_FILES) \
-			$(linked_module) \
-			$(symbolic_output) \
-			$(compress_output)
+$(cleantarget): PRIVATE_CLEAN_FILES += \
+    $(linked_module) \
+    $(symbolic_output) \
+    $(compress_output)