[PATCH 4.19 097/148] kbuild: consolidate Clang compiler flags

From: Greg Kroah-Hartman
Date: Fri Jan 11 2019 - 09:39:07 EST


4.19-stable review patch. If anyone has any objections, please let me know.

------------------

From: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx>

commit 238bcbc4e07fad2fff99c5b157d0c37ccd4d093c upstream.

Collect basic Clang options such as --target, --prefix, --gcc-toolchain,
-no-integrated-as into a single variable CLANG_FLAGS so that it can be
easily reused in other parts of Makefile.

Signed-off-by: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx>
Reviewed-by: Nick Desaulniers <ndesaulniers@xxxxxxxxxx>
Tested-by: Nick Desaulniers <ndesaulniers@xxxxxxxxxx>
Acked-by: Greg Hackmann <ghackmann@xxxxxxxxxx>
Signed-off-by: Nathan Chancellor <natechancellor@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
Makefile | 13 ++++++-------
1 file changed, 6 insertions(+), 7 deletions(-)

--- a/Makefile
+++ b/Makefile
@@ -482,18 +482,17 @@ endif

ifeq ($(cc-name),clang)
ifneq ($(CROSS_COMPILE),)
-CLANG_TARGET := --target=$(notdir $(CROSS_COMPILE:%-=%))
+CLANG_FLAGS := --target=$(notdir $(CROSS_COMPILE:%-=%))
GCC_TOOLCHAIN_DIR := $(dir $(shell which $(LD)))
-CLANG_PREFIX := --prefix=$(GCC_TOOLCHAIN_DIR)
+CLANG_FLAGS += --prefix=$(GCC_TOOLCHAIN_DIR)
GCC_TOOLCHAIN := $(realpath $(GCC_TOOLCHAIN_DIR)/..)
endif
ifneq ($(GCC_TOOLCHAIN),)
-CLANG_GCC_TC := --gcc-toolchain=$(GCC_TOOLCHAIN)
+CLANG_FLAGS += --gcc-toolchain=$(GCC_TOOLCHAIN)
endif
-KBUILD_CFLAGS += $(CLANG_TARGET) $(CLANG_GCC_TC) $(CLANG_PREFIX)
-KBUILD_AFLAGS += $(CLANG_TARGET) $(CLANG_GCC_TC) $(CLANG_PREFIX)
-KBUILD_CFLAGS += -no-integrated-as
-KBUILD_AFLAGS += -no-integrated-as
+CLANG_FLAGS += -no-integrated-as
+KBUILD_CFLAGS += $(CLANG_FLAGS)
+KBUILD_AFLAGS += $(CLANG_FLAGS)
endif

RETPOLINE_CFLAGS_GCC := -mindirect-branch=thunk-extern -mindirect-branch-register