diff --git a/core/cleanbuild.mk b/core/cleanbuild.mk
index a753554..7e68d6f 100644
--- a/core/cleanbuild.mk
+++ b/core/cleanbuild.mk
@@ -16,28 +16,40 @@
 INTERNAL_CLEAN_STEPS :=
 
 # Builds up a list of clean steps.  Creates a unique
-# id for each step by taking INTERNAL_CLEAN_BUILD_VERSION
+# id for each step by taking makefile path, INTERNAL_CLEAN_BUILD_VERSION
 # and appending an increasing number of '@' characters.
 #
 # $(1): shell command to run
+# $(2): indicate to not use makefile path as part of step id if not empty.
+#       $(2) should only be used in build/core/cleanspec.mk: just for compatibility.
 define _add-clean-step
   $(if $(strip $(INTERNAL_CLEAN_BUILD_VERSION)),, \
       $(error INTERNAL_CLEAN_BUILD_VERSION not set))
-  $(eval _acs_id := $(strip $(lastword $(INTERNAL_CLEAN_STEPS))))
-  $(if $(_acs_id),,$(eval _acs_id := $(INTERNAL_CLEAN_BUILD_VERSION)))
-  $(eval _acs_id := $(_acs_id)@)
+  $(eval _acs_makefile_prefix := $(lastword $(MAKEFILE_LIST)))
+  $(eval _acs_makefile_prefix := $(subst /,_,$(_acs_makefile_prefix)))
+  $(eval _acs_makefile_prefix := $(subst .,-,$(_acs_makefile_prefix)))
+  $(eval _acs_makefile_prefix := $(_acs_makefile_prefix)_acs)
+  $(if $($(_acs_makefile_prefix)),,\
+      $(eval $(_acs_makefile_prefix) := $(INTERNAL_CLEAN_BUILD_VERSION)))
+  $(eval $(_acs_makefile_prefix) := $($(_acs_makefile_prefix))@)
+  $(if $(strip $(2)),$(eval _acs_id := $($(_acs_makefile_prefix))),\
+      $(eval _acs_id := $(_acs_makefile_prefix)$($(_acs_makefile_prefix))))
   $(eval INTERNAL_CLEAN_STEPS += $(_acs_id))
   $(eval INTERNAL_CLEAN_STEP.$(_acs_id) := $(1))
   $(eval _acs_id :=)
+  $(eval _acs_makefile_prefix :=)
 endef
 define add-clean-step
-$(if $(call _add-clean-step,$(1)),)
+$(eval # for build/core/cleanspec.mk, dont use makefile path as part of step id) \
+$(if $(filter %/cleanspec.mk,$(lastword $(MAKEFILE_LIST))),\
+    $(eval $(call _add-clean-step,$(1),true)),\
+    $(eval $(call _add-clean-step,$(1))))
 endef
 
 # Defines INTERNAL_CLEAN_BUILD_VERSION and the individual clean steps.
 # cleanspec.mk is outside of the core directory so that more people
 # can have permission to touch it.
-include build/cleanspec.mk
+include $(BUILD_SYSTEM)/cleanspec.mk
 INTERNAL_CLEAN_BUILD_VERSION := $(strip $(INTERNAL_CLEAN_BUILD_VERSION))
 
 # If the clean_steps.mk file is missing (usually after a clean build)
diff --git a/core/cleanspec.mk b/core/cleanspec.mk
new file mode 100644
index 0000000..c95dda6
--- /dev/null
+++ b/core/cleanspec.mk
@@ -0,0 +1,171 @@
+# Copyright (C) 2007 The Android Open Source Project
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+
+# Just bump this if you want to force a clean build.
+# **********************************************************************
+# WHEN DOING SO
+# 1. DELETE ANY "add-clean-step" ENTRIES THAT HAVE PILED UP IN THIS FILE.
+# 2. REMOVE ALL FILES NAMED CleanSpec.mk.
+# 3. BUMP THE VERSION.
+# IDEALLY, THOSE STEPS SHOULD BE DONE ATOMICALLY.
+# **********************************************************************
+#
+INTERNAL_CLEAN_BUILD_VERSION := 3
+#
+# ***********************************************************************
+# Do not touch INTERNAL_CLEAN_BUILD_VERSION if you've added a clean step!
+# ***********************************************************************
+
+# If you don't need to do a full clean build but would like to touch
+# a file or delete some intermediate files, add a clean step to the end
+# of the list.  These steps will only be run once, if they haven't been
+# run before.
+#
+# E.g.:
+#     $(call add-clean-step, touch -c external/sqlite/sqlite3.h)
+#     $(call add-clean-step, rm -rf $(PRODUCT_OUT)/obj/STATIC_LIBRARIES/libz_intermediates)
+#
+# Always use "touch -c" and "rm -f" or "rm -rf" to gracefully deal with
+# files that are missing or have been moved.
+#
+# Use $(PRODUCT_OUT) to get to the "out/target/product/blah/" directory.
+# Use $(OUT_DIR) to refer to the "out" directory.
+#
+# If you need to re-do something that's already mentioned, just copy
+# the command and add it to the bottom of the list.  E.g., if a change
+# that you made last week required touching a file and a change you
+# made today requires touching the same file, just copy the old
+# touch step and add it to the end of the list.
+#
+# ************************************************
+# NEWER CLEAN STEPS MUST BE AT THE END OF THE LIST
+# ************************************************
+
+# For example:
+#$(call add-clean-step, rm -rf $(OUT_DIR)/target/common/obj/APPS/AndroidTests_intermediates)
+#$(call add-clean-step, rm -rf $(OUT_DIR)/target/common/obj/JAVA_LIBRARIES/core_intermediates)
+#$(call add-clean-step, find $(OUT_DIR) -type f -name "IGTalkSession*" -print0 | xargs -0 rm -f)
+#$(call add-clean-step, rm -rf $(PRODUCT_OUT)/data/*)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/obj/SHARED_LIBRARIES/libwebcore_intermediates)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/obj/STATIC_LIBRARIES/libwebcore_intermediates)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/obj/SHARED_LIBRARIES/libwebcore_intermediates)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/obj/STATIC_LIBRARIES/libwebcore_intermediates)
+$(call add-clean-step, rm -rf $(OUT_DIR)/target/common/obj/JAVA_LIBRARIES/com.google.android.datamessaging_intermediates)
+$(call add-clean-step, rm -rf $(OUT_DIR)/target/product/sholes/obj/SHARED_LIBRARIES/libhardware_legacy_intermediates)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/system/etc/pvasflocal.cfg)
+$(call add-clean-step, rm -rf $(OUT_DIR)/target/product/sholes)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/obj/SHARED_LIBRARIES/libwebcore_intermediates)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/obj/STATIC_LIBRARIES/libwebcore_intermediates)
+$(call add-clean-step, rm -rf $(OUT_DIR)/target/common/obj/JAVA_LIBRARIES/framework_intermediates)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/system/media/audio/ringtones/Silence.ogg)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/system/media/audio/ringtones/notifications/Silence.ogg)
+$(call add-clean-step, rm -rf $(OUT_DIR)/target/product/passion/obj/SHARED_LIBRARIES/libhardware_legacy_intermediates)
+$(call add-clean-step, rm -rf $(OUT_DIR)/target/common/obj/JAVA_LIBRARIES/com.google.android.datamessaging_intermediates)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/obj/SHARED_LIBRARIES/libcrypto_intermediates)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/obj/SHARED_LIBRARIES/libssl_intermediates)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/obj/EXECUTABLES/openssl_intermediates)
+$(call add-clean-step, rm -rf $(OUT_DIR)/target/product/sholes/system/build.prop)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/obj/SHARED_LIBRARIES/libwebcore_intermediates)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/obj/STATIC_LIBRARIES/libwebcore_intermediates)
+$(call add-clean-step, rm -rf $(OUT_DIR)/target/common/obj/JAVA_LIBRARIES/framework_intermediates)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/system/bin/bugreport)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/obj/SHARED_LIBRARIES/libwebcore_intermediates)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/obj/STATIC_LIBRARIES/libwebcore_intermediates)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/obj/SHARED_LIBRARIES/libdvm_intermediates)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/obj/SHARED_LIBRARIES/libandroid_runtime_intermediates)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/obj/STATIC_LIBRARIES/libwebcore_intermediates)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/obj/SHARED_LIBRARIES/libwebcore_intermediates)
+$(call add-clean-step, rm -rf $(OUT_DIR)/obj/target/common/obj/APPS/VoiceSearch_intermediates)
+$(call add-clean-step, rm -rf $(OUT_DIR)/target/common/obj/APPS/VoiceSearch_intermediates)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/obj/STATIC_LIBRARIES/libgps-rpc_intermediates)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/obj/STATIC_LIBRARIES/pdsm_atl_intermediates)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/obj/SHARED_LIBRARIES/libgps_intermediates)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/obj/SHARED_LIBRARIES/libhardware_legacy_intermediates)
+$(call add-clean-step, rm -rf $(OUT_DIR)/target/product/*/system/app/Launcher.apk)
+$(call add-clean-step, rm -rf $(OUT_DIR)/target/common/obj/JAVA_LIBRARIES/framework_intermediates/src/core/java/android/bluetooth/)
+$(call add-clean-step, rm -rf $(OUT_DIR)/target/product/sholes/system/build.prop)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/obj/APPS/com.amazon.mp3_intermediates)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/system/app/com.amazon.mp3.apk)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/system/build.prop)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/obj/APPS)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/system/app)
+$(call add-clean-step, rm -rf $(OUT_DIR)/target/common/obj/APPS)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/system/build.prop)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/obj/SHARED_LIBRARIES/libwebcore_intermediates)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/obj/STATIC_LIBRARIES/libwebcore_intermediates)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/obj/)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/obj/APPS)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/system/app)
+$(call add-clean-step, rm -rf $(OUT_DIR)/target/common/obj/APPS)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/system/build.prop)
+$(call add-clean-step, rm -rf $(OUT_DIR)/target/common/obj/JAVA_LIBRARIES/framework_intermediates)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/obj/EXECUTABLES/openssl_intermediates)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/obj/SHARED_LIBRARIES/libwebcore_intermediates)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/obj/STATIC_LIBRARIES/libwebcore_intermediates)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/obj/STATIC_LIBRARIES/libv8_intermediates)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/obj/SHARED_LIBRARIES/libwebcore_intermediates)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/obj/STATIC_LIBRARIES/libwebcore_intermediates)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/obj/STATIC_LIBRARIES/libjs_intermediates)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/obj/STATIC_LIBRARIES/libv8_intermediates)
+$(call add-clean-step, rm -rf $(OUT_DIR)/target/common/obj/JAVA_LIBRARIES/framework_intermediates/src/core/java/com/android/internal/os/IDropBoxService.java)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/obj/APPS)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/system/app)
+$(call add-clean-step, rm -rf $(OUT_DIR)/target/common/obj/APPS)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/system/build.prop)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/system/app/GoogleSubscribedFeedsProvider.apk)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/system/build.prop)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/system/build.prop)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/obj/APPS)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/system/app)
+$(call add-clean-step, rm -rf $(OUT_DIR)/target/common/obj/APPS)
+$(call add-clean-step, rm -rf $(OUT_DIR)/target/common/obj/JAVA_LIBRARIES/framework_intermediates)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/obj/SHARED_LIBRARIES/libhardware_legacy_intermediates)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/system/build.prop)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/obj/APPS)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/system/app)
+$(call add-clean-step, rm -rf $(OUT_DIR)/target/common/obj/APPS)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/obj/SHARED_LIBRARIES/libmediaplayerservice_intermediates)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/obj/SHARED_LIBRARIES/libstagefright_intermediates)
+$(call add-clean-step, rm -rf $(OUT_DIR)/target/common/obj/APPS/GoogleServicesFramework_intermediates)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/system/app/VoiceSearchWithKeyboard.apk)
+$(call add-clean-step, rm -rf $(OUT_DIR)/target/common/obj/APPS/Email_intermediates)
+$(call add-clean-step, rm -rf $(OUT_DIR)/target/common/obj/APPS/Email_intermediates)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/obj/vendor/google_voiceime)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/system/app/QuickSearchBox.apk)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/obj/SHARED_LIBRARIES/libdvm_intermediates)
+$(call add-clean-step, rm -rf $(OUT_DIR)/target/common/obj/JAVA_LIBRARIES/framework_intermediates/src/core/java/android/speech)
+$(call add-clean-step, rm -rf $(OUT_DIR)/target/common/obj/APPS/Email_intermediates)
+$(call add-clean-step, rm -rf $(OUT_DIR)/target/common/obj/APPS/AndroidTests_intermediates)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/system/app/EnhancedGoogleSearchProvider.apk)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/system/app/*)
+$(call add-clean-step, rm -rf $(OUT_DIR)/target/common/obj/JAVA_LIBRARIES/framework_intermediates)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/system/app/GoogleCheckin.apk)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/obj/SHARED_LIBRARIES/libdvm*)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/obj/STATIC_LIBRARIES/libgtest_main_intermediates)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/obj/STATIC_LIBRARIES/libgtest_intermediates)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/obj/APPS/Music*)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/system/app/Music*)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/obj/APPS/Music*)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/system/app/Music*)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/system/app/Launcher.apk)
+
+# ************************************************
+# NEWER CLEAN STEPS MUST BE AT THE END OF THE LIST
+# ************************************************
+
+subdir_cleanspecs := \
+    $(shell build/tools/findleaves.py --prune=out --prune=.repo --prune=.git . CleanSpec.mk)
+include $(subdir_cleanspecs)
+subdir_cleanspecs :=