[PATCH 1/2] x86: Use -mno-avx when available

From: Andi Kleen
Date: Wed Mar 28 2012 - 14:51:42 EST


From: Andi Kleen <ak@xxxxxxxxxxxxxxx>

On gccs that support AVX it's a good idea to disable that too, similar to
how SSE2, SSE1 etc. are already disabled. This prevents the compiler
from generating AVX ever implicitely.

No failure observed, just from review.

Signed-off-by: Andi Kleen <ak@xxxxxxxxxxxxxxx>
---
arch/x86/Makefile | 1 +
1 files changed, 1 insertions(+), 0 deletions(-)

diff --git a/arch/x86/Makefile b/arch/x86/Makefile
index 209ba12..2c8aefd 100644
--- a/arch/x86/Makefile
+++ b/arch/x86/Makefile
@@ -113,6 +113,7 @@ KBUILD_CFLAGS += -Wno-sign-compare
KBUILD_CFLAGS += -fno-asynchronous-unwind-tables
# prevent gcc from generating any FP code by mistake
KBUILD_CFLAGS += $(call cc-option,-mno-sse -mno-mmx -mno-sse2 -mno-3dnow,)
+KBUILD_CFLAGS += $(call cc-option,-mno-avx,)

KBUILD_CFLAGS += $(mflags-y)
KBUILD_AFLAGS += $(mflags-y)
--
1.7.7.6

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