[PATCH] x86: set fpmath to 387 to avoid gcc warnings

From: dragos . tatulea
Date: Mon Aug 06 2012 - 07:35:57 EST


From: Dragos Tatulea <dragos.tatulea@xxxxxxxxx>

If gcc has a different default fpmath set (e.g. sse),
many unuseful warnings will be spewed when compiling on an
architecture that doesn't support it.

An example would be Google's Android 4.1 x86 toochain which
is compiled with -mfpmath=sse.

This can affect out of tree modules that compile with
-Werror (ex: systemtap stp scripts).

Signed-off-by: Dragos Tatulea <dragos.tatulea@xxxxxxxxx>
---
arch/x86/Makefile | 1 +
1 file changed, 1 insertion(+)

diff --git a/arch/x86/Makefile b/arch/x86/Makefile
index b1c611e..f4fefb8 100644
--- a/arch/x86/Makefile
+++ b/arch/x86/Makefile
@@ -130,6 +130,7 @@ 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 += $(call cc-option,-mfpmath=387,)

KBUILD_CFLAGS += $(mflags-y)
KBUILD_AFLAGS += $(mflags-y)
--
1.7.9.5

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