Move selection of C++ STL into the build system.

Preparing for migration from stlport to libc++. STL selection is done
with LOCAL_CXX_STL (valid values are default, none, libc++,
libc++_static, stlport, stlport_static, bionic).

The selection of the STL is as follows:

    if LOCAL_CXX_STL == 'default'
      ifdef LOCAL_SDK_VERSION
        Use whatever STL the other NDK options have selected.
      else
        Use bionic's libstdc++ for target, GNU libstdc++ for host. This
        is compatible with the existing build options.
      endif
    else
      if LOCAL_CXX_STL == 'stlport'
        Use stlport.
      else if LOCAL_CXX_STL == 'libc++'
        Use libc++.
      else if LOCAL_CXX_STL == ''
        Don't use any STL.
      endif
    endif

Bug: 15193147
Change-Id: If712ba0ae7908d8147a69e29da5c453a183d6540

9 files changed, 78 insertions, 23 deletions

diff --git a/core/binary.mk b/core/binary.mk
index 60cd4c6..936b429 100644
--- a/core/binary.mk
+++ b/core/binary.mk
@@ -107,6 +107,7 @@ my_shared_libraries := $(LOCAL_SHARED_LIBRARIES)
 my_cflags := $(LOCAL_CFLAGS)
 my_cppflags := $(LOCAL_CPPFLAGS)
 my_ldflags := $(LOCAL_LDFLAGS)
+my_ldlibs := $(LOCAL_LDLIBS)
 my_asflags := $(LOCAL_ASFLAGS)
 my_cc := $(LOCAL_CC)
 my_cxx := $(LOCAL_CXX)
@@ -164,11 +165,66 @@ my_whole_static_libraries := $(LOCAL_WHOLE_STATIC_LIBRARIES_$($(my_prefix)$(LOCA
 
 my_cflags := $(filter-out $($(LOCAL_2ND_ARCH_VAR_PREFIX)$(my_prefix)GLOBAL_UNSUPPORTED_CFLAGS),$(my_cflags))
 
+# Only around for development purposes. Will be removed soon.
+my_libcxx_is_default := false
+
+# Select the appropriate C++ STL
+ifeq ($(strip $(LOCAL_CXX_STL)),default)
+    ifndef LOCAL_SDK_VERSION
+        ifeq ($(strip $(my_libcxx_is_default)),true)
+            # Platform code. Select the appropriate STL.
+            my_cxx_stl := libc++
+        else
+            my_cxx_stl := bionic
+        endif
+    else
+        my_cxx_stl := ndk
+    endif
+else
+    my_cxx_stl := $(strip $(LOCAL_CXX_STL))
+endif
+
+ifneq ($(filter $(my_cxx_stl),libc++ libc++_static),)
+    my_cflags += -D_USING_LIBCXX
+    my_c_includes += external/libcxx/include
+    ifeq ($(my_cxx_stl),libc++)
+        my_shared_libraries += libc++
+    else
+        my_static_libraries += libc++_static
+    endif
 
-# Replace libstdc++ with libc++ if it's seen
-my_libcxx := $(filter libc++, $(my_shared_libraries))
-ifdef my_libcxx
-my_system_shared_libraries := $(filter-out libstdc++, $(my_system_shared_libraries))
+    ifdef LOCAL_IS_HOST_MODULE
+        my_cppflags += -nostdinc++
+        my_ldflags += -nodefaultlibs
+        my_ldlibs += -lc -lm
+    endif
+else ifneq ($(filter $(my_cxx_stl),stlport stlport_static),)
+    my_c_includes += external/stlport/stlport bionic/libstdc++/include bionic
+    ifeq ($(my_cxx_stl),stlport)
+        my_shared_libraries += libstdc++ libstlport
+    else
+        my_static_libraries += libstdc++ libstlport_static
+    endif
+else ifeq ($(my_cxx_stl),ndk)
+    # Using an NDK STL. Handled farther up in this file.
+    ifndef LOCAL_IS_HOST_MODULE
+        my_system_shared_libraries += libstdc++
+    endif
+else ifeq ($(my_cxx_stl),bionic)
+    # Using bionic's basic libstdc++. Not actually an STL. Only around until the
+    # tree is in good enough shape to not need it.
+    ifndef LOCAL_IS_HOST_MODULE
+        my_c_includes += bionic/libstdc++/include
+        my_system_shared_libraries += libstdc++
+    endif
+    # Host builds will use GNU libstdc++.
+else ifeq ($(my_cxx_stl),none)
+    ifdef LOCAL_IS_HOST_MODULE
+        my_cppflags += -nostdinc++
+        my_ldflags += -nodefaultlibs -lc -lm
+    endif
+else
+    $(error $(my_cxx_stl) is not a supported STL.)
 endif
 
 # Add static HAL libraries
@@ -947,7 +1003,7 @@ $(LOCAL_INTERMEDIATE_TARGETS): PRIVATE_DEBUG_CFLAGS := $(debug_cflags)
 $(LOCAL_INTERMEDIATE_TARGETS): PRIVATE_C_INCLUDES := $(my_c_includes)
 $(LOCAL_INTERMEDIATE_TARGETS): PRIVATE_IMPORT_INCLUDES := $(import_includes)
 $(LOCAL_INTERMEDIATE_TARGETS): PRIVATE_LDFLAGS := $(my_ldflags)
-$(LOCAL_INTERMEDIATE_TARGETS): PRIVATE_LDLIBS := $(LOCAL_LDLIBS)
+$(LOCAL_INTERMEDIATE_TARGETS): PRIVATE_LDLIBS := $(my_ldlibs)
 $(LOCAL_INTERMEDIATE_TARGETS): PRIVATE_NO_CRT := $(strip $(LOCAL_NO_CRT) $(LOCAL_NO_CRT_$(TARGET_$(LOCAL_2ND_ARCH_VAR_PREFIX)ARCH)))
 $(LOCAL_INTERMEDIATE_TARGETS): PRIVATE_LIBCXX := $(my_libcxx)
 
diff --git a/core/clear_vars.mk b/core/clear_vars.mk
index baa32e2..61a0927 100644
--- a/core/clear_vars.mk
+++ b/core/clear_vars.mk
@@ -157,6 +157,7 @@ LOCAL_MODULE_UNSUPPORTED_TARGET_ARCH:=
 LOCAL_MODULE_UNSUPPORTED_TARGET_ARCH_WARN:=
 LOCAL_MODULE_HOST_ARCH:=
 LOCAL_NO_FPIE :=
+LOCAL_CXX_STL := default
 
 # arch specific variables
 LOCAL_SRC_FILES_$(TARGET_ARCH):=
diff --git a/core/combo/TARGET_linux-arm.mk b/core/combo/TARGET_linux-arm.mk
index 7c7f1f4..c9a34e7 100644
--- a/core/combo/TARGET_linux-arm.mk
+++ b/core/combo/TARGET_linux-arm.mk
@@ -153,7 +153,6 @@ $(combo_2nd_arch_prefix)TARGET_RELEASE_CFLAGS := \
 
 libc_root := bionic/libc
 libm_root := bionic/libm
-libstdc++_root := bionic/libstdc++
 
 
 ## on some hosts, the target cross-compiler is not available so do not run this command
@@ -176,7 +175,6 @@ KERNEL_HEADERS := $(KERNEL_HEADERS_COMMON) $(KERNEL_HEADERS_ARCH)
 $(combo_2nd_arch_prefix)TARGET_C_INCLUDES := \
 	$(libc_root)/arch-arm/include \
 	$(libc_root)/include \
-	$(libstdc++_root)/include \
 	$(KERNEL_HEADERS) \
 	$(libm_root)/include \
 	$(libm_root)/include/arm \
@@ -190,7 +188,7 @@ $(combo_2nd_arch_prefix)TARGET_CRTEND_SO_O := $($(combo_2nd_arch_prefix)TARGET_O
 
 $(combo_2nd_arch_prefix)TARGET_STRIP_MODULE:=true
 
-$(combo_2nd_arch_prefix)TARGET_DEFAULT_SYSTEM_SHARED_LIBRARIES := libc libstdc++ libm
+$(combo_2nd_arch_prefix)TARGET_DEFAULT_SYSTEM_SHARED_LIBRARIES := libc libm
 
 $(combo_2nd_arch_prefix)TARGET_CUSTOM_LD_COMMAND := true
 
diff --git a/core/combo/TARGET_linux-arm64.mk b/core/combo/TARGET_linux-arm64.mk
index 3cef5e5..82eb7fd 100644
--- a/core/combo/TARGET_linux-arm64.mk
+++ b/core/combo/TARGET_linux-arm64.mk
@@ -126,7 +126,6 @@ TARGET_RELEASE_CFLAGS := \
 
 libc_root := bionic/libc
 libm_root := bionic/libm
-libstdc++_root := bionic/libstdc++
 
 TARGET_LIBGCC := $(shell $(TARGET_CC) $(TARGET_GLOBAL_CFLAGS) \
 	-print-libgcc-file-name)
@@ -140,7 +139,6 @@ KERNEL_HEADERS := $(KERNEL_HEADERS_COMMON) $(KERNEL_HEADERS_ARCH)
 TARGET_C_INCLUDES := \
 	$(libc_root)/arch-arm64/include \
 	$(libc_root)/include \
-	$(libstdc++_root)/include \
 	$(KERNEL_HEADERS) \
 	$(libm_root)/include \
 	$(libm_root)/include/arm64 \
@@ -154,7 +152,7 @@ TARGET_CRTEND_SO_O := $(TARGET_OUT_INTERMEDIATE_LIBRARIES)/crtend_so.o
 
 TARGET_STRIP_MODULE:=true
 
-TARGET_DEFAULT_SYSTEM_SHARED_LIBRARIES := libc libstdc++ libm
+TARGET_DEFAULT_SYSTEM_SHARED_LIBRARIES := libc libm
 
 TARGET_CUSTOM_LD_COMMAND := true
 
diff --git a/core/combo/TARGET_linux-mips.mk b/core/combo/TARGET_linux-mips.mk
index 5ec537a..92ad21a 100644
--- a/core/combo/TARGET_linux-mips.mk
+++ b/core/combo/TARGET_linux-mips.mk
@@ -121,7 +121,6 @@ $(combo_2nd_arch_prefix)TARGET_RELEASE_CFLAGS := \
 
 libc_root := bionic/libc
 libm_root := bionic/libm
-libstdc++_root := bionic/libstdc++
 
 
 ## on some hosts, the target cross-compiler is not available so do not run this command
@@ -148,7 +147,6 @@ KERNEL_HEADERS := $(KERNEL_HEADERS_COMMON) $(KERNEL_HEADERS_ARCH)
 $(combo_2nd_arch_prefix)TARGET_C_INCLUDES := \
 	$(libc_root)/arch-mips/include \
 	$(libc_root)/include \
-	$(libstdc++_root)/include \
 	$(KERNEL_HEADERS) \
 	$(libm_root)/include \
 	$(libm_root)/include/mips \
@@ -162,7 +160,7 @@ $(combo_2nd_arch_prefix)TARGET_CRTEND_SO_O := $($(combo_2nd_arch_prefix)TARGET_O
 
 $(combo_2nd_arch_prefix)TARGET_STRIP_MODULE:=true
 
-$(combo_2nd_arch_prefix)TARGET_DEFAULT_SYSTEM_SHARED_LIBRARIES := libc libstdc++ libm
+$(combo_2nd_arch_prefix)TARGET_DEFAULT_SYSTEM_SHARED_LIBRARIES := libc libm
 
 $(combo_2nd_arch_prefix)TARGET_CUSTOM_LD_COMMAND := true
 
diff --git a/core/combo/TARGET_linux-mips64.mk b/core/combo/TARGET_linux-mips64.mk
index a2e64c5..3435814 100644
--- a/core/combo/TARGET_linux-mips64.mk
+++ b/core/combo/TARGET_linux-mips64.mk
@@ -121,7 +121,6 @@ TARGET_RELEASE_CFLAGS := \
 
 libc_root := bionic/libc
 libm_root := bionic/libm
-libstdc++_root := bionic/libstdc++
 libthread_db_root := bionic/libthread_db
 
 
@@ -150,7 +149,6 @@ KERNEL_HEADERS := $(KERNEL_HEADERS_COMMON) $(KERNEL_HEADERS_ARCH)
 TARGET_C_INCLUDES := \
 	$(libc_root)/arch-mips64/include \
 	$(libc_root)/include \
-	$(libstdc++_root)/include \
 	$(KERNEL_HEADERS) \
 	$(libm_root)/include \
 	$(libm_root)/include/mips \
diff --git a/core/combo/TARGET_linux-x86.mk b/core/combo/TARGET_linux-x86.mk
index c17a8ef..6e5f5ac 100644
--- a/core/combo/TARGET_linux-x86.mk
+++ b/core/combo/TARGET_linux-x86.mk
@@ -70,7 +70,6 @@ $(combo_2nd_arch_prefix)TARGET_NO_UNDEFINED_LDFLAGS := -Wl,--no-undefined
 
 libc_root := bionic/libc
 libm_root := bionic/libm
-libstdc++_root := bionic/libstdc++
 
 KERNEL_HEADERS_COMMON := $(libc_root)/kernel/uapi
 KERNEL_HEADERS_ARCH   := $(libc_root)/kernel/uapi/asm-x86 # x86 covers both x86 and x86_64.
@@ -130,7 +129,6 @@ $(combo_2nd_arch_prefix)TARGET_GLOBAL_LDFLAGS += -Wl,--gc-sections
 $(combo_2nd_arch_prefix)TARGET_C_INCLUDES := \
 	$(libc_root)/arch-x86/include \
 	$(libc_root)/include \
-	$(libstdc++_root)/include \
 	$(KERNEL_HEADERS) \
 	$(libm_root)/include \
 	$(libm_root)/include/i387 \
@@ -144,7 +142,7 @@ $(combo_2nd_arch_prefix)TARGET_CRTEND_SO_O := $($(combo_2nd_arch_prefix)TARGET_O
 
 $(combo_2nd_arch_prefix)TARGET_STRIP_MODULE:=true
 
-$(combo_2nd_arch_prefix)TARGET_DEFAULT_SYSTEM_SHARED_LIBRARIES := libc libstdc++ libm
+$(combo_2nd_arch_prefix)TARGET_DEFAULT_SYSTEM_SHARED_LIBRARIES := libc libm
 
 $(combo_2nd_arch_prefix)TARGET_CUSTOM_LD_COMMAND := true
 define $(combo_2nd_arch_prefix)transform-o-to-shared-lib-inner
diff --git a/core/combo/TARGET_linux-x86_64.mk b/core/combo/TARGET_linux-x86_64.mk
index 905dfff..0fb8795 100644
--- a/core/combo/TARGET_linux-x86_64.mk
+++ b/core/combo/TARGET_linux-x86_64.mk
@@ -70,7 +70,6 @@ TARGET_NO_UNDEFINED_LDFLAGS := -Wl,--no-undefined
 
 libc_root := bionic/libc
 libm_root := bionic/libm
-libstdc++_root := bionic/libstdc++
 
 KERNEL_HEADERS_COMMON := $(libc_root)/kernel/uapi
 KERNEL_HEADERS_ARCH   := $(libc_root)/kernel/uapi/asm-x86 # x86 covers both x86 and x86_64.
@@ -135,7 +134,6 @@ TARGET_GLOBAL_LDFLAGS += -Wl,--gc-sections
 TARGET_C_INCLUDES := \
 	$(libc_root)/arch-x86_64/include \
 	$(libc_root)/include \
-	$(libstdc++_root)/include \
 	$(KERNEL_HEADERS) \
 	$(libm_root)/include \
 	$(libm_root)/include/amd64 \
@@ -149,7 +147,7 @@ TARGET_CRTEND_SO_O := $(TARGET_OUT_INTERMEDIATE_LIBRARIES)/crtend_so.o
 
 TARGET_STRIP_MODULE:=true
 
-TARGET_DEFAULT_SYSTEM_SHARED_LIBRARIES := libc libstdc++ libm
+TARGET_DEFAULT_SYSTEM_SHARED_LIBRARIES := libc libm
 
 TARGET_CUSTOM_LD_COMMAND := true
 define transform-o-to-shared-lib-inner
diff --git a/core/target_test_internal.mk b/core/target_test_internal.mk
index 95d4159..6b147b1 100644
--- a/core/target_test_internal.mk
+++ b/core/target_test_internal.mk
@@ -5,7 +5,17 @@
 LOCAL_CFLAGS += -DGTEST_OS_LINUX_ANDROID -DGTEST_HAS_STD_STRING
 
 LOCAL_C_INCLUDES += external/gtest/include
-ifneq ($(filter libc++,$(LOCAL_SHARED_LIBRARIES)),)
+
+my_test_libcxx := false
+ifndef LOCAL_SDK_VERSION
+ifeq (,$(TARGET_BUILD_APPS))
+ifeq ($(strip $(LOCAL_CXX_STL)),libc++)
+my_test_libcxx := true
+endif
+endif
+endif
+
+ifeq ($(my_test_libcxx),true)
 LOCAL_STATIC_LIBRARIES += libgtest_libc++ libgtest_main_libc++
 else
 LOCAL_STATIC_LIBRARIES += libgtest libgtest_main