linker: use LOCAL_MULTILIB := both style to build linker64

Use LOCAL_MODULE_STEM_32 and LOCAL_MODULE_STEM_64 to build
linker and linker64.  Set LOCAL_MULTILIB := both for consistency
with other rules of this type, although LOCAL_MULTILIB := both is
only consumed by executable.mk which is skipped by
linker_executable.mk.  Duplicate the necessary new parts of
executable.mk.

Change-Id: I888e87cf125cfbcfdee6a55b6377d8bc5ce402ea

linker/Android.mk

@@ -1,9 +1,70 @@
 LOCAL_PATH:= $(call my-dir)
 
-linker_2nd_arch_var_prefix :=
-include $(LOCAL_PATH)/linker.mk
+LOCAL_PATH:= $(call my-dir)
+include $(CLEAR_VARS)
 
+LOCAL_SRC_FILES:= \
+    debugger.cpp \
+    dlfcn.cpp \
+    linker.cpp \
+    linker_environ.cpp \
+    linker_phdr.cpp \
+    rt.cpp \
+
+LOCAL_SRC_FILES_arm     := arch/arm/begin.S
+LOCAL_SRC_FILES_arm64   := arch/arm64/begin.S
+LOCAL_SRC_FILES_x86     := arch/x86/begin.c
+LOCAL_SRC_FILES_x86_64  := arch/x86_64/begin.S
+LOCAL_SRC_FILES_mips    := arch/mips/begin.S
+
+LOCAL_LDFLAGS := \
+    -shared \
+    -Wl,-Bsymbolic \
+    -Wl,--exclude-libs,ALL \
+
+LOCAL_CFLAGS += \
+    -fno-stack-protector \
+    -Wstrict-overflow=5 \
+    -fvisibility=hidden \
+    -Wall -Wextra -Werror \
+
+LOCAL_CONLYFLAGS += \
+    -std=gnu99 \
+
+LOCAL_CPPFLAGS += \
+    -std=gnu++11 \
+
+# We need to access Bionic private headers in the linker.
+LOCAL_CFLAGS += -I$(LOCAL_PATH)/../libc/
+
+# we don't want crtbegin.o (because we have begin.o), so unset it
+# just for this module
+LOCAL_NO_CRT := true
+# TODO: split out the asflags.
+LOCAL_ASFLAGS := $(LOCAL_CFLAGS)
+
+LOCAL_ADDITIONAL_DEPENDENCIES := $(LOCAL_PATH)/Android.mk $(LOCAL_PATH)/linker_executable.mk
+
+LOCAL_STATIC_LIBRARIES := libc_nomalloc
+
+LOCAL_FORCE_STATIC_EXECUTABLE := true # not necessary when not including BUILD_EXECUTABLE
+
+LOCAL_2ND_ARCH_VAR_PREFIX := $(linker_2nd_arch_var_prefix)
+
+LOCAL_MODULE := linker
+LOCAL_MODULE_STEM_32 := linker
+LOCAL_MODULE_STEM_64 := linker64
+LOCAL_MULTILIB := both
+
+include $(LOCAL_PATH)/linker_executable.mk
 ifdef TARGET_2ND_ARCH
-linker_2nd_arch_var_prefix := $(TARGET_2ND_ARCH_VAR_PREFIX)
-include $(LOCAL_PATH)/linker.mk
+LOCAL_2ND_ARCH_VAR_PREFIX := $(TARGET_2ND_ARCH_VAR_PREFIX)
+OVERRIDE_BUILT_MODULE_PATH :=
+LOCAL_BUILT_MODULE :=
+LOCAL_INSTALLED_MODULE :=
+LOCAL_MODULE_STEM :=
+LOCAL_BUILT_MODULE_STEM :=
+LOCAL_INSTALLED_MODULE_STEM :=
+LOCAL_INTERMEDIATE_TARGETS :=
+include $(LOCAL_PATH)/linker_executable.mk
 endif

linker/linker.mk

@@ -1,58 +0,0 @@
-LOCAL_PATH:= $(call my-dir)
-include $(CLEAR_VARS)
-
-LOCAL_SRC_FILES:= \
-    debugger.cpp \
-    dlfcn.cpp \
-    linker.cpp \
-    linker_environ.cpp \
-    linker_phdr.cpp \
-    rt.cpp \
-
-LOCAL_SRC_FILES_arm     := arch/arm/begin.S
-LOCAL_SRC_FILES_arm64   := arch/arm64/begin.S
-LOCAL_SRC_FILES_x86     := arch/x86/begin.c
-LOCAL_SRC_FILES_x86_64  := arch/x86_64/begin.S
-LOCAL_SRC_FILES_mips    := arch/mips/begin.S
-
-LOCAL_LDFLAGS := \
-    -shared \
-    -Wl,-Bsymbolic \
-    -Wl,--exclude-libs,ALL \
-
-LOCAL_CFLAGS += \
-    -fno-stack-protector \
-    -Wstrict-overflow=5 \
-    -fvisibility=hidden \
-    -Wall -Wextra -Werror \
-
-LOCAL_CONLYFLAGS += \
-    -std=gnu99 \
-
-LOCAL_CPPFLAGS += \
-    -std=gnu++11 \
-
-# We need to access Bionic private headers in the linker.
-LOCAL_CFLAGS += -I$(LOCAL_PATH)/../libc/
-
-# we don't want crtbegin.o (because we have begin.o), so unset it
-# just for this module
-LOCAL_NO_CRT := true
-# TODO: split out the asflags.
-LOCAL_ASFLAGS := $(LOCAL_CFLAGS)
-
-LOCAL_ADDITIONAL_DEPENDENCIES := $(LOCAL_PATH)/Android.mk $(LOCAL_PATH)/linker.mk $(LOCAL_PATH)/linker_executable.mk
-
-LOCAL_STATIC_LIBRARIES := libc_nomalloc
-
-LOCAL_FORCE_STATIC_EXECUTABLE := true # not necessary when not including BUILD_EXECUTABLE
-
-LOCAL_2ND_ARCH_VAR_PREFIX := $(linker_2nd_arch_var_prefix)
-
-ifeq ($(TARGET_IS_64_BIT)|$(linker_2nd_arch_var_prefix),true|)
-LOCAL_MODULE := linker64
-else
-LOCAL_MODULE := linker
-endif
-
-include $(LOCAL_PATH)/linker_executable.mk