diff --git a/core/config.mk b/core/config.mk
index c993c1b..debe918 100644
--- a/core/config.mk
+++ b/core/config.mk
@@ -665,14 +665,28 @@
 
 COLUMN:= column
 
-# Path to tools.jar, or empty if EXPERIMENTAL_USE_OPENJDK9 is set
+ifeq ($(EXPERIMENTAL_USE_OPENJDK9),)
+USE_OPENJDK9 :=
+TARGET_OPENJDK9 :=
+else ifeq ($(EXPERIMENTAL_USE_OPENJDK9),false)
+USE_OPENJDK9 :=
+TARGET_OPENJDK9 :=
+else ifeq ($(EXPERIMENTAL_USE_OPENJDK9),1.8)
+USE_OPENJDK9 := true
+TARGET_OPENJDK9 :=
+else ifeq ($(EXPERIMENTAL_USE_OPENJDK9),true)
+USE_OPENJDK9 := true
+TARGET_OPENJDK9 := true
+endif
+
+# Path to tools.jar, or empty if USE_OPENJDK9 is unset
 HOST_JDK_TOOLS_JAR :=
 # TODO: Remove HOST_JDK_TOOLS_JAR and all references to it once OpenJDK 8
-# toolchains are no longer supported (i.e. when what is now
-# EXPERIMENTAL_USE_OPENJDK9 becomes the standard). http://b/38418220
-ifeq ($(EXPERIMENTAL_USE_OPENJDK9),)
+# toolchains are no longer supported (i.e. when USE_OPENJDK9 is enforced).
+# http://b/38418220
+ifndef USE_OPENJDK9
 HOST_JDK_TOOLS_JAR := $(ANDROID_JAVA_TOOLCHAIN)/../lib/tools.jar
-endif # ifeq ($(EXPERIMENTAL_USE_OPENJDK9),)
+endif # ifdef USE_OPENJDK9
 
 # It's called md5 on Mac OS and md5sum on Linux
 ifeq ($(HOST_OS),darwin)
diff --git a/core/definitions.mk b/core/definitions.mk
index 8b4051d..13bd47c 100644
--- a/core/definitions.mk
+++ b/core/definitions.mk
@@ -2381,7 +2381,7 @@
 @rm -rf $(dir $@)/desugar_dumped_classes
 @mkdir $(dir $@)/desugar_dumped_classes
 $(hide) $(JAVA) \
-    $(if $(EXPERIMENTAL_USE_OPENJDK9),--add-opens java.base/java.lang.invoke=ALL-UNNAMED,) \
+    $(if $(USE_OPENJDK9),--add-opens java.base/java.lang.invoke=ALL-UNNAMED,) \
     -Djdk.internal.lambda.dumpProxyClasses=$(abspath $(dir $@))/desugar_dumped_classes \
     -jar $(DESUGAR) \
     $(addprefix --bootclasspath_entry ,$(PRIVATE_BOOTCLASSPATH)) \
@@ -2774,7 +2774,7 @@
 ###########################################################
 ## Commands to call Proguard
 ###########################################################
-ifeq ($(EXPERIMENTAL_USE_OPENJDK9),true)
+ifdef TARGET_OPENJDK9
 define transform-jar-to-proguard
 @echo Skipping Proguard: $<$(PRIVATE_PROGUARD_INJAR_FILTERS) $@
 $(hide) cp '$<' $@
diff --git a/core/droiddoc.mk b/core/droiddoc.mk
index 45b8af0..d66b688 100644
--- a/core/droiddoc.mk
+++ b/core/droiddoc.mk
@@ -213,7 +213,7 @@
 ##
 ##
 
-ifneq ($(EXPERIMENTAL_USE_OPENJDK9),)
+ifdef USE_OPENJDK9
 # For OpenJDK 9 we use --patch-module to define the core libraries code.
 # TODO(tobiast): Reorganize this when adding proper support for OpenJDK 9
 # modules. Here we treat all code in core libraries as being in java.base
diff --git a/core/java.mk b/core/java.mk
index 09e5371..7fa1447 100644
--- a/core/java.mk
+++ b/core/java.mk
@@ -555,7 +555,7 @@
 
 $(eval $(call copy-one-file,$(full_classes_jarjar_jar),$(full_classes_jar)))
 
-ifeq ($(EXPERIMENTAL_USE_OPENJDK9),true)
+ifdef TARGET_OPENJDK9
 LOCAL_DX_FLAGS := $(filter-out --multi-dex,$(LOCAL_DX_FLAGS)) --multi-dex
 endif
 
diff --git a/core/java_common.mk b/core/java_common.mk
index 37de700..6ae1415 100644
--- a/core/java_common.mk
+++ b/core/java_common.mk
@@ -23,8 +23,7 @@
     # TODO(ccross): allow 1.9 for current and unbundled once we have SDK system modules
     LOCAL_JAVA_LANGUAGE_VERSION := 1.8
   else
-    # DEFAULT_JAVA_LANGUAGE_VERSION is 1.8 unless EXPERIMENTAL_USE_OPENJDK9=true
-    # in which case it is 1.9
+    # DEFAULT_JAVA_LANGUAGE_VERSION is 1.8, unless TARGET_OPENJDK9 in which case it is 1.9
     LOCAL_JAVA_LANGUAGE_VERSION := $(DEFAULT_JAVA_LANGUAGE_VERSION)
   endif
 endif