[PATCH] x86: turn off -fcf-protection for realmode

From: Arnd Bergmann
Date: Tue Mar 23 2021 - 08:49:43 EST

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From: Arnd Bergmann <arnd@xxxxxxxx>

The new Ubuntu gcc packages turn on -fcf-protection globally,
which causes a build failure in the x86 realmode code:

cc1: error: ‘-fcf-protection’ is not compatible with this target

Turn it off explicitly on compilers that understand this option.

Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
---
arch/x86/Makefile | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/Makefile b/arch/x86/Makefile
index 5689d799bd12..0a1278512cc9 100644
--- a/arch/x86/Makefile
+++ b/arch/x86/Makefile
@@ -27,7 +27,7 @@ endif
REALMODE_CFLAGS := -m16 -Os -DDISABLE_BRANCH_PROFILING \
-Wall -Wstrict-prototypes -march=i386 -mregparm=3 \
-fno-strict-aliasing -fomit-frame-pointer -fno-pic \
- -mno-mmx -mno-sse
+ -mno-mmx -mno-sse $(call cc-option,-fcf-protection=none)

REALMODE_CFLAGS += -ffreestanding
REALMODE_CFLAGS += -fno-stack-protector
--
2.29.2