diff --git a/core/binary.mk b/core/binary.mk
index ebb40c8..cd8982c 100644
--- a/core/binary.mk
+++ b/core/binary.mk
@@ -451,7 +451,6 @@
 ifeq ($(LOCAL_CPP_EXTENSION),)
   LOCAL_CPP_EXTENSION := .cpp
 endif
-$(LOCAL_INTERMEDIATE_TARGETS): PRIVATE_CPP_EXTENSION := $(LOCAL_CPP_EXTENSION)
 
 # Certain modules like libdl have to have symbols resolved at runtime and blow
 # up if --no-undefined is passed to the linker.
@@ -763,79 +762,57 @@
 endif  # $(aidl_src) non-empty
 
 ###########################################################
-## YACC: Compile .y and .yy files to .cpp and the to .o.
+## YACC: Compile .y/.yy files to .c/.cpp and then to .o.
 ###########################################################
 
 y_yacc_sources := $(filter %.y,$(my_src_files))
-y_yacc_cpps := $(addprefix \
-    $(intermediates)/,$(y_yacc_sources:.y=$(LOCAL_CPP_EXTENSION)))
+y_yacc_cs := $(addprefix \
+    $(intermediates)/,$(y_yacc_sources:.y=.c))
+ifneq ($(y_yacc_cs),)
+$(y_yacc_cs): $(intermediates)/%.c: \
+    $(TOPDIR)$(LOCAL_PATH)/%.y \
+    $(my_additional_dependencies)
+	$(call transform-y-to-c-or-cpp)
+
+my_generated_sources += $(y_yacc_cs)
+endif
 
 yy_yacc_sources := $(filter %.yy,$(my_src_files))
 yy_yacc_cpps := $(addprefix \
     $(intermediates)/,$(yy_yacc_sources:.yy=$(LOCAL_CPP_EXTENSION)))
-
-yacc_cpps := $(y_yacc_cpps) $(yy_yacc_cpps)
-yacc_headers := $(yacc_cpps:$(LOCAL_CPP_EXTENSION)=.h)
-yacc_objects := $(yacc_cpps:$(LOCAL_CPP_EXTENSION)=.o)
-
-ifneq ($(strip $(y_yacc_cpps)),)
-$(y_yacc_cpps): $(intermediates)/%$(LOCAL_CPP_EXTENSION): \
-    $(TOPDIR)$(LOCAL_PATH)/%.y \
-    $(lex_cpps) $(my_additional_dependencies)
-	$(call transform-y-to-cpp,$(PRIVATE_CPP_EXTENSION))
-$(yacc_headers): $(intermediates)/%.h: $(intermediates)/%$(LOCAL_CPP_EXTENSION)
-endif
-
-ifneq ($(strip $(yy_yacc_cpps)),)
+ifneq ($(yy_yacc_cpps),)
 $(yy_yacc_cpps): $(intermediates)/%$(LOCAL_CPP_EXTENSION): \
     $(TOPDIR)$(LOCAL_PATH)/%.yy \
-    $(lex_cpps) $(my_additional_dependencies)
-	$(call transform-y-to-cpp,$(PRIVATE_CPP_EXTENSION))
-$(yacc_headers): $(intermediates)/%.h: $(intermediates)/%$(LOCAL_CPP_EXTENSION)
-endif
+    $(my_additional_dependencies)
+	$(call transform-y-to-c-or-cpp)
 
-ifneq ($(strip $(yacc_cpps)),)
-$(yacc_objects): PRIVATE_ARM_MODE := $(normal_objects_mode)
-$(yacc_objects): PRIVATE_ARM_CFLAGS := $(normal_objects_cflags)
-$(yacc_objects): $(intermediates)/%.o: $(intermediates)/%$(LOCAL_CPP_EXTENSION)
-	$(transform-$(PRIVATE_HOST)cpp-to-o)
+my_generated_sources += $(yy_yacc_cpps)
 endif
 
 ###########################################################
-## LEX: Compile .l and .ll files to .cpp and then to .o.
+## LEX: Compile .l/.ll files to .c/.cpp and then to .o.
 ###########################################################
 
 l_lex_sources := $(filter %.l,$(my_src_files))
-l_lex_cpps := $(addprefix \
-    $(intermediates)/,$(l_lex_sources:.l=$(LOCAL_CPP_EXTENSION)))
+l_lex_cs := $(addprefix \
+    $(intermediates)/,$(l_lex_sources:.l=.c))
+ifneq ($(l_lex_cs),)
+$(l_lex_cs): $(intermediates)/%.c: \
+    $(TOPDIR)$(LOCAL_PATH)/%.l
+	$(transform-l-to-c-or-cpp)
+
+my_generated_sources += $(l_lex_cs)
+endif
 
 ll_lex_sources := $(filter %.ll,$(my_src_files))
 ll_lex_cpps := $(addprefix \
     $(intermediates)/,$(ll_lex_sources:.ll=$(LOCAL_CPP_EXTENSION)))
-
-lex_cpps := $(l_lex_cpps) $(ll_lex_cpps)
-lex_objects := $(lex_cpps:$(LOCAL_CPP_EXTENSION)=.o)
-
-ifneq ($(strip $(l_lex_cpps)),)
-$(l_lex_cpps): $(intermediates)/%$(LOCAL_CPP_EXTENSION): \
-    $(TOPDIR)$(LOCAL_PATH)/%.l
-	$(transform-l-to-cpp)
-endif
-
-ifneq ($(strip $(ll_lex_cpps)),)
+ifneq ($(ll_lex_cpps),)
 $(ll_lex_cpps): $(intermediates)/%$(LOCAL_CPP_EXTENSION): \
     $(TOPDIR)$(LOCAL_PATH)/%.ll
-	$(transform-l-to-cpp)
-endif
+	$(transform-l-to-c-or-cpp)
 
-ifneq ($(strip $(lex_cpps)),)
-$(lex_objects): PRIVATE_ARM_MODE := $(normal_objects_mode)
-$(lex_objects): PRIVATE_ARM_CFLAGS := $(normal_objects_cflags)
-$(lex_objects): $(intermediates)/%.o: \
-    $(intermediates)/%$(LOCAL_CPP_EXTENSION) \
-    $(my_additional_dependencies) \
-    $(yacc_headers)
-	$(transform-$(PRIVATE_HOST)cpp-to-o)
+my_generated_sources += $(ll_lex_cpps)
 endif
 
 ###########################################################
@@ -1140,8 +1117,6 @@
     $(gen_c_objects) \
     $(objc_objects) \
     $(objcpp_objects) \
-    $(yacc_objects) \
-    $(lex_objects) \
     $(proto_generated_objects) \
     $(addprefix $(TOPDIR)$(LOCAL_PATH)/,$(LOCAL_PREBUILT_OBJ_FILES))
 
diff --git a/core/config.mk b/core/config.mk
index 26c354d..47eb60d 100644
--- a/core/config.mk
+++ b/core/config.mk
@@ -536,8 +536,6 @@
 # Tool to merge AndroidManifest.xmls
 ANDROID_MANIFEST_MERGER := java -classpath prebuilts/devtools/tools/lib/manifest-merger.jar com.android.manifmerger.Main merge
 
-YACC_HEADER_SUFFIX:= .hpp
-
 COLUMN:= column
 
 # We may not have the right JAVA_HOME/PATH set up yet when this is run from envsetup.sh.
diff --git a/core/definitions.mk b/core/definitions.mk
index a6218cc..5fe126d 100644
--- a/core/definitions.mk
+++ b/core/definitions.mk
@@ -875,7 +875,7 @@
 ## Commands for running lex
 ###########################################################
 
-define transform-l-to-cpp
+define transform-l-to-c-or-cpp
 @echo "Lex: $(PRIVATE_MODULE) <= $<"
 @mkdir -p $(dir $@)
 $(hide) $(LEX) -o$@ $<
@@ -884,20 +884,14 @@
 ###########################################################
 ## Commands for running yacc
 ##
-## Because the extension of c++ files can change, the
-## extension must be specified in $1.
-## E.g, "$(call transform-y-to-cpp,.cpp)"
 ###########################################################
 
-define transform-y-to-cpp
+define transform-y-to-c-or-cpp
 @echo "Yacc: $(PRIVATE_MODULE) <= $<"
 @mkdir -p $(dir $@)
-$(YACC) $(PRIVATE_YACCFLAGS) -o $@ $<
-touch $(@:$1=$(YACC_HEADER_SUFFIX))
-echo '#ifndef '$(@F:$1=_h) > $(@:$1=.h)
-echo '#define '$(@F:$1=_h) >> $(@:$1=.h)
-cat $(@:$1=$(YACC_HEADER_SUFFIX)) >> $(@:$1=.h)
-echo '#endif' >> $(@:$1=.h)
+$(YACC) $(PRIVATE_YACCFLAGS) \
+  --defines=$(basename $@).h \
+  -o $@ $<
 endef
 
 ###########################################################