On Mon, Oct 29, 2018 at 10:10 AM ndesaulniers@google.com wrote:
From: Tri Vo trong@android.com
commit 2a6c7c367de82951c98a290a21156770f6f82c84 upstream
x0 is not callee-saved in the PCS. So there is no need to specify -fcall-used-x0.
Clang doesn't currently support -fcall-used flags. This patch will help building the kernel with clang.
Tested-by: Nick Desaulniers ndesaulniers@google.com Acked-by: Will Deacon will.deacon@arm.com Signed-off-by: Tri Vo trong@android.com Signed-off-by: Catalin Marinas catalin.marinas@arm.com Signed-off-by: Nick Desaulniers ndesaulniers@google.com
Sending to stable for inclusion in 4.14. Needed for CONFIG_ARM64_LSE_ATOMICS.
Please take this patch into 4.9 too.
arch/arm64/lib/Makefile | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/arm64/lib/Makefile b/arch/arm64/lib/Makefile index f28f91fd96a2..69ff9887f724 100644 --- a/arch/arm64/lib/Makefile +++ b/arch/arm64/lib/Makefile @@ -12,7 +12,7 @@ lib-y := clear_user.o delay.o copy_from_user.o \ # when supported by the CPU. Result and argument registers are handled # correctly, based on the function prototype. lib-$(CONFIG_ARM64_LSE_ATOMICS) += atomic_ll_sc.o -CFLAGS_atomic_ll_sc.o := -fcall-used-x0 -ffixed-x1 -ffixed-x2 \ +CFLAGS_atomic_ll_sc.o := -ffixed-x1 -ffixed-x2 \ -ffixed-x3 -ffixed-x4 -ffixed-x5 -ffixed-x6 \ -ffixed-x7 -fcall-saved-x8 -fcall-saved-x9 \ -fcall-saved-x10 -fcall-saved-x11 -fcall-saved-x12 \ -- 2.19.1.568.g152ad8e336-goog