Re: [PATCH v2 1/5] powerpc/Makefiles: Fix clang/llvm build
From: Nick Desaulniers <ndesaulniers@google.com>
Date: 2018-09-14 17:41:56
On Thu, Sep 13, 2018 at 9:07 PM Joel Stanley [off-list ref] wrote:
From: Anton Blanchard <redacted>
Commit 15a3204d24a3 ("powerpc/64s: Set assembler machine type to POWER4")
passes -mpower4 to the assembler. We have more recent instructions in our
assembly files, but gas permits them. The clang/llvm integrated assembler
is more strict, and we get a build failure.Note that we disable clang's integrated assembler in the top level Makefile for now, but it will still validate constraints for inline assembly. Do you know which case is meant by "build failure?" Is there a link to the Clang bug? It would be good to have that context in the commit message.
quoted hunk ↗ jump to hunk
Fix this by calling the assembler with -mcpu=power8 if as supports it, else fall back to power4. Suggested-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Anton Blanchard <redacted> Signed-off-by: Joel Stanley <joel@jms.id.au> --- arch/powerpc/Makefile | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)diff --git a/arch/powerpc/Makefile b/arch/powerpc/Makefile index 11a1acba164a..a70639482053 100644 --- a/arch/powerpc/Makefile +++ b/arch/powerpc/Makefile@@ -238,7 +238,7 @@ cpu-as-$(CONFIG_4xx) += -Wa,-m405 cpu-as-$(CONFIG_ALTIVEC) += $(call as-option,-Wa$(comma)-maltivec) cpu-as-$(CONFIG_E200) += -Wa,-me200 cpu-as-$(CONFIG_E500) += -Wa,-me500 -cpu-as-$(CONFIG_PPC_BOOK3S_64) += -Wa,-mpower4 +cpu-as-$(CONFIG_PPC_BOOK3S_64) += $(call as-option,-Wa$(comma)-mpower8,-Wa$(comma)-mpower4) cpu-as-$(CONFIG_PPC_E500MC) += $(call as-option,-Wa$(comma)-me500mc) KBUILD_AFLAGS += $(cpu-as-y) --2.17.1
-- Thanks, ~Nick Desaulniers