[PATCH] MIPS: VDSO: Always select -msoft-float

[Guenter Roeck <linux@roeck-us.net>]

Some toolchains fail to build mips images with the following build error.

arch/mips/vdso/gettimeofday.c:1:0: error: '-march=r3000' requires '-mfp32'

This is seen, for example, with the 'mipsel-linux-gnu-gcc (Debian 6.1.1-9)
6.1.1 20160705' toolchain as used by the 0Day build robot when building
decstation_defconfig.

Comparison of compile flags suggests that the major difference is a missing
'-soft-float', which is otherwise defined unconditionally.

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Cc: James Hogan <james.hogan@imgtec.com>
Fixes: ebb5e78cc634 ("MIPS: Initial implementation of a VDSO")
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
---
 arch/mips/vdso/Makefile | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/arch/mips/vdso/Makefile b/arch/mips/vdso/Makefile
index c3dc12a8b7d9..9bdd6641400f 100644
--- a/arch/mips/vdso/Makefile
+++ b/arch/mips/vdso/Makefile
@@ -6,7 +6,8 @@ ccflags-vdso := \
 	$(filter -I%,$(KBUILD_CFLAGS)) \
 	$(filter -E%,$(KBUILD_CFLAGS)) \
 	$(filter -mmicromips,$(KBUILD_CFLAGS)) \
-	$(filter -march=%,$(KBUILD_CFLAGS))
+	$(filter -march=%,$(KBUILD_CFLAGS)) \
+	-msoft-float
 cflags-vdso := $(ccflags-vdso) \
 	$(filter -W%,$(filter-out -Wa$(comma)%,$(KBUILD_CFLAGS))) \
 	-O2 -g -fPIC -fno-strict-aliasing -fno-common -fno-builtin -G 0 \
-- 
2.5.0