[PATCH] ARM: pass -msoft-float to gcc earlier

From: Arnd Bergmann
Date: Tue May 19 2020 - 18:09:48 EST


Szabolcs Nagy ran into a kernel build failure with a custom gcc
toochain that sets -mfpu=auto -mfloat-abi=hard:

/tmp/ccmNdcdf.s:1898: Error: selected processor does not support `cpsid i' in ARM mode

The problem is that $(call cc-option, -march=armv7-a) fails before the
kernel overrides the gcc options to also pass -msoft-float.

Move the option to the beginning the Makefile, before we call
cc-option for the first time.

Reported-by: Szabolcs Nagy <szabolcs.nagy@xxxxxxx>
Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=87302
Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
---
arch/arm/Makefile | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/arch/arm/Makefile b/arch/arm/Makefile
index 7d5cd0f85461..e428ea6eb0fa 100644
--- a/arch/arm/Makefile
+++ b/arch/arm/Makefile
@@ -16,6 +16,8 @@ LDFLAGS_vmlinux += --be8
KBUILD_LDFLAGS_MODULE += --be8
endif

+KBUILD_CFLAGS += -msoft-float
+
ifeq ($(CONFIG_ARM_MODULE_PLTS),y)
KBUILD_LDS_MODULE += $(srctree)/arch/arm/kernel/module.lds
endif
@@ -135,7 +137,7 @@ AFLAGS_ISA :=$(CFLAGS_ISA)
endif

# Need -Uarm for gcc < 3.x
-KBUILD_CFLAGS +=$(CFLAGS_ABI) $(CFLAGS_ISA) $(arch-y) $(tune-y) $(call cc-option,-mshort-load-bytes,$(call cc-option,-malignment-traps,)) -msoft-float -Uarm
+KBUILD_CFLAGS +=$(CFLAGS_ABI) $(CFLAGS_ISA) $(arch-y) $(tune-y) $(call cc-option,-mshort-load-bytes,$(call cc-option,-malignment-traps,)) -Uarm
KBUILD_AFLAGS +=$(CFLAGS_ABI) $(AFLAGS_ISA) $(arch-y) $(tune-y) -include asm/unified.h -msoft-float

CHECKFLAGS += -D__arm__
--
2.26.2