[PATCH] [19/45] x86_64: Always accumulate compiler options in CFLAGS

From: Andi Kleen
Date: Fri Sep 21 2007 - 16:51:57 EST



This way they are used in further down cc-options tries
This avoids a problem with a probe not failing without -m64.
Analysis of original bug by Andy Whitcroft

TBD do for i386 too

Signed-off-by: Andi Kleen <ak@xxxxxxx>

---
arch/x86_64/Makefile | 62 +++++++++++++++++++++++++++------------------------
1 file changed, 33 insertions(+), 29 deletions(-)

Index: linux/arch/x86_64/Makefile
===================================================================
--- linux.orig/arch/x86_64/Makefile
+++ linux/arch/x86_64/Makefile
@@ -26,50 +26,54 @@ OBJCOPYFLAGS := -O binary -R .note -R .c
LDFLAGS_vmlinux :=
CHECKFLAGS += -D__x86_64__ -m64

-cflags-y :=
-cflags-kernel-y :=
-cflags-$(CONFIG_MK8) += $(call cc-option,-march=k8)
-cflags-$(CONFIG_MPSC) += $(call cc-option,-march=nocona)
-# gcc doesn't support -march=core2 yet as of gcc 4.3, but I hope it
-# will eventually. Use -mtune=generic as fallback
-cflags-$(CONFIG_MCORE2) += \
- $(call cc-option,-march=core2,$(call cc-option,-mtune=generic))
-cflags-$(CONFIG_GENERIC_CPU) += $(call cc-option,-mtune=generic)
-
-cflags-y += -m64
-cflags-y += -mno-red-zone
-cflags-y += -mcmodel=kernel
-cflags-y += -pipe
-cflags-y += -Wno-sign-compare
-cflags-y += -fno-asynchronous-unwind-tables
-ifneq ($(CONFIG_DEBUG_INFO),y)
+AFLAGS += -m64
+CFLAGS += -m64
+CFLAGS += -mno-red-zone
+CFLAGS += -mcmodel=kernel
+CFLAGS += -pipe
+CFLAGS += -Wno-sign-compare
+CFLAGS += -fno-asynchronous-unwind-tables
+#ifneq ($(CONFIG_DEBUG_INFO),y)
# -fweb shrinks the kernel a bit, but the difference is very small
# it also messes up debugging, so don't use it for now.
-#cflags-y += $(call cc-option,-fweb)
-endif
+#CFLAGS += $(call cc-option,-fweb)
+#endif
# -funit-at-a-time shrinks the kernel .text considerably
# unfortunately it makes reading oopses harder.
-cflags-y += $(call cc-option,-funit-at-a-time)
+CFLAGS += $(call cc-option,-funit-at-a-time)
# prevent gcc from generating any FP code by mistake
-cflags-y += $(call cc-option,-mno-sse -mno-mmx -mno-sse2 -mno-3dnow,)
+CFLAGS += $(call cc-option,-mno-sse -mno-mmx -mno-sse2 -mno-3dnow,)
# this works around some issues with generating unwind tables in older gccs
# newer gccs do it by default
-cflags-y += -maccumulate-outgoing-args
+CFLAGS += -maccumulate-outgoing-args

# do binutils support CFI?
-cflags-y += $(call as-instr,.cfi_startproc\n.cfi_rel_offset rsp${comma}0\n.cfi_endproc,-DCONFIG_AS_CFI=1,)
+CFLAGS += $(call as-instr,.cfi_startproc\n.cfi_rel_offset rsp${comma}0\n.cfi_endproc,-DCONFIG_AS_CFI=1,)
AFLAGS += $(call as-instr,.cfi_startproc\n.cfi_rel_offset rsp${comma}0\n.cfi_endproc,-DCONFIG_AS_CFI=1,)

# is .cfi_signal_frame supported too?
-cflags-y += $(call as-instr,.cfi_startproc\n.cfi_signal_frame\n.cfi_endproc,-DCONFIG_AS_CFI_SIGNAL_FRAME=1,)
+CFLAGS += $(call as-instr,.cfi_startproc\n.cfi_signal_frame\n.cfi_endproc,-DCONFIG_AS_CFI_SIGNAL_FRAME=1,)
AFLAGS += $(call as-instr,.cfi_startproc\n.cfi_signal_frame\n.cfi_endproc,-DCONFIG_AS_CFI_SIGNAL_FRAME=1,)
+CFLAGS_KERNEL += $(cflags-kernel-y)

-cflags-$(CONFIG_CC_STACKPROTECTOR) += $(shell $(CONFIG_SHELL) $(srctree)/scripts/gcc-x86_64-has-stack-protector.sh "$(CC)" -fstack-protector )
-cflags-$(CONFIG_CC_STACKPROTECTOR_ALL) += $(shell $(CONFIG_SHELL) $(srctree)/scripts/gcc-x86_64-has-stack-protector.sh "$(CC)" -fstack-protector-all )
+# CFLAGS is used by cc-option, so if combinations fail we notice

-CFLAGS += $(cflags-y)
-CFLAGS_KERNEL += $(cflags-kernel-y)
-AFLAGS += -m64
+cflags-k8-$(CONFIG_MK8) += $(call cc-option,-march=k8)
+CFLAGS += $(cflags-k8-y)
+
+cflags-nocona-$(CONFIG_MPSC) += $(call cc-option,-march=nocona)
+CFLAGS += $(cflags-nocona-y)
+# gcc doesn't support -march=core2 yet as of gcc 4.3, but I hope it
+# will eventually. Use -mtune=generic as fallback
+cflags-core2-$(CONFIG_MCORE2) += \
+ $(call cc-option,-march=core2,$(call cc-option,-mtune=generic))
+CFLAGS += $(cflags-core2-y)
+cflags-generic-$(CONFIG_GENERIC_CPU) += $(call cc-option,-mtune=generic)
+CFLAGS += $(cflags-generic-y)
+
+cflags-sp-$(CONFIG_CC_STACKPROTECTOR) += $(shell $(CONFIG_SHELL) $(srctree)/scripts/gcc-x86_64-has-stack-protector.sh "$(CC)" -fstack-protector )
+cflags-sp-$(CONFIG_CC_STACKPROTECTOR_ALL) += $(shell $(CONFIG_SHELL) $(srctree)/scripts/gcc-x86_64-has-stack-protector.sh "$(CC)" -fstack-protector-all )
+CFLAGS += $(cflags-sp-y)

head-y := arch/x86_64/kernel/head.o arch/x86_64/kernel/head64.o arch/x86_64/kernel/init_task.o

-
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