[PATCH 1/3] [RESEND] ARM: pass -march=armv7-a when building NEON files with clang

From: Arnd Bergmann
Date: Thu Feb 18 2016 - 12:06:10 EST


clang ignores the -mfpu=neon flag when building with -march=armv6:

In file included from lib/raid6/neon1.c:27:
clang/3.8.0/include/arm_neon.h:28:2: error: "NEON support not enabled"

There is no real need to build the file with -march=armv6 in a
multi-CPU enabled kernel, as nothing in here will ever get called
on an ARMv6 CPU. Adding -march=armv7 doesn't hurt and can only
improve the code quality.

Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
---
arch/arm/lib/Makefile | 2 +-
lib/raid6/Makefile | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/arm/lib/Makefile b/arch/arm/lib/Makefile
index d8a780799506..a86c6c8e0648 100644
--- a/arch/arm/lib/Makefile
+++ b/arch/arm/lib/Makefile
@@ -35,7 +35,7 @@ $(obj)/csumpartialcopy.o: $(obj)/csumpartialcopygeneric.S
$(obj)/csumpartialcopyuser.o: $(obj)/csumpartialcopygeneric.S

ifeq ($(CONFIG_KERNEL_MODE_NEON),y)
- NEON_FLAGS := -mfloat-abi=softfp -mfpu=neon
+ NEON_FLAGS := -mfloat-abi=softfp -mfpu=neon -march=armv7-a
CFLAGS_xor-neon.o += $(NEON_FLAGS)
obj-$(CONFIG_XOR_BLOCKS) += xor-neon.o
endif
diff --git a/lib/raid6/Makefile b/lib/raid6/Makefile
index 3b10a48fa040..4ef3e800fb39 100644
--- a/lib/raid6/Makefile
+++ b/lib/raid6/Makefile
@@ -23,7 +23,7 @@ endif
ifeq ($(CONFIG_KERNEL_MODE_NEON),y)
NEON_FLAGS := -ffreestanding
ifeq ($(ARCH),arm)
-NEON_FLAGS += -mfloat-abi=softfp -mfpu=neon
+NEON_FLAGS += -mfloat-abi=softfp -mfpu=neon -march=armv7-a
endif
ifeq ($(ARCH),arm64)
CFLAGS_REMOVE_neon1.o += -mgeneral-regs-only
--
2.7.0