[PATCH] [0/2] Updated patches for gold -X probing

[PATCH] [0/2] Updated patches for gold -X probing

[Andi Kleen]

based on Sam's feedback using a new macro.

gold build doesn't work currently for some other reasons,
but I haven't investigated that yet. It seems to be new though,
wasn't there a few rc*s ago.

-Andi

[PATCH] [1/2] kbuild: Add a really-ld-option macro

[Andi Kleen]

Different from the existing ld macro by checking $(LD)

Needed for the next patch

Signed-off-by: Andi Kleen <ak@linux.intel.com>

---
 scripts/Kbuild.include |    9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

Index: linux-2.6.31-ak/scripts/Kbuild.include
===================================================================
--- linux-2.6.31-ak.orig/scripts/Kbuild.include
+++ linux-2.6.31-ak/scripts/Kbuild.include
@@ -83,11 +83,12 @@ TMPOUT := $(if $(KBUILD_EXTMOD),$(firstw
 # is automatically cleaned up.
 try-run = $(shell set -e;		\
 	TMP="$(TMPOUT).$$$$.tmp";	\
+	TMPO="$(TMPOUT).$$$$.o";	\
 	if ($(1)) >/dev/null 2>&1;	\
 	then echo "$(2)";		\
 	else echo "$(3)";		\
 	fi;				\
-	rm -f "$$TMP")
+	rm -f "$$TMP" "$$TMPO")
 
 # as-option
 # Usage: cflags-y += $(call as-option,-Wa$(comma)-isa=foo,)
@@ -135,6 +136,12 @@ cc-ifversion = $(shell [ $(call cc-versi
 ld-option = $(call try-run,\
 	$(CC) $(1) -nostdlib -xc /dev/null -o "$$TMP",$(1),$(2))
 
+# really-ld-option
+# checks $(LD) unlike ld-option
+# Usage: LDFLAGS += $(call really-ld-option, -X)
+really-ld-option = $(call try-run,\
+	$(CC) /dev/null -c -o "$$TMPO" ; $(LD) $(1) "$$TMPO" -o "$$TMP",$(1),$(2))
+
 ######
 
 ###

Re: [PATCH] [1/2] kbuild: Add a really-ld-option macro

[Sam Ravnborg]

On Wed, Sep 16, 2009 at 10:36:54PM +0200, Andi Kleen wrote:
> 
> Different from the existing ld macro by checking $(LD)
> 
> Needed for the next patch
> 
> Signed-off-by: Andi Kleen <ak@linux.intel.com>
> 
> ---
>  scripts/Kbuild.include |    9 ++++++++-
>  1 file changed, 8 insertions(+), 1 deletion(-)
> 
> Index: linux-2.6.31-ak/scripts/Kbuild.include
> ===================================================================
> --- linux-2.6.31-ak.orig/scripts/Kbuild.include
> +++ linux-2.6.31-ak/scripts/Kbuild.include
> @@ -83,11 +83,12 @@ TMPOUT := $(if $(KBUILD_EXTMOD),$(firstw
>  # is automatically cleaned up.
>  try-run = $(shell set -e;		\
>  	TMP="$(TMPOUT).$$$$.tmp";	\
> +	TMPO="$(TMPOUT).$$$$.o";	\
>  	if ($(1)) >/dev/null 2>&1;	\
>  	then echo "$(2)";		\
>  	else echo "$(3)";		\
>  	fi;				\
> -	rm -f "$$TMP")
> +	rm -f "$$TMP" "$$TMPO")
>  
>  # as-option
>  # Usage: cflags-y += $(call as-option,-Wa$(comma)-isa=foo,)
> @@ -135,6 +136,12 @@ cc-ifversion = $(shell [ $(call cc-versi
>  ld-option = $(call try-run,\
>  	$(CC) $(1) -nostdlib -xc /dev/null -o "$$TMP",$(1),$(2))
>  
> +# really-ld-option
> +# checks $(LD) unlike ld-option
> +# Usage: LDFLAGS += $(call really-ld-option, -X)
> +really-ld-option = $(call try-run,\
> +	$(CC) /dev/null -c -o "$$TMPO" ; $(LD) $(1) "$$TMPO" -o "$$TMP",$(1),$(2))
> +

kbuild has some strange marcro names - but adding more is no good.
I will:
1) rename ld-option to cc-ldoption
2) add ld-option, and _document_ it in makefiles.txt
3) use ld-option for the -X option

I had preferred your patchset did so.

	Sam

[PATCH] [2/2] kbuild: Check if linker supports the -X option

[Andi Kleen]

The new alternative `gold' linker in recent binutils doesn't support
the -X option. This breaks allyesconfig builds that have 
CONFIG_STRIP_ASM_SYMS enabled. Check if the linker really supports
the option using ld-option.

This requires fixes in earlier patches.

Signed-off-by: Andi Kleen <ak@linux.intel.com>

---
 Makefile |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Index: linux-2.6.31-rc3-ak/Makefile
===================================================================
--- linux-2.6.31-rc3-ak.orig/Makefile
+++ linux-2.6.31-rc3-ak/Makefile
@@ -600,7 +600,7 @@ LDFLAGS_MODULE += $(LDFLAGS_BUILD_ID)
 LDFLAGS_vmlinux += $(LDFLAGS_BUILD_ID)
 
 ifeq ($(CONFIG_STRIP_ASM_SYMS),y)
-LDFLAGS_vmlinux	+= -X
+LDFLAGS_vmlinux	+= $(call really-ld-option, -X,)
 endif
 
 # Default kernel image to build when no specific target is given.

Re: [PATCH] [0/2] Updated patches for gold -X probing

[Américo Wang]

On Thu, Sep 17, 2009 at 4:36 AM, Andi Kleen <andi@firstfloor.org> wrote:
>
> based on Sam's feedback using a new macro.
>
> gold build doesn't work currently for some other reasons,
> but I haven't investigated that yet. It seems to be new though,
> wasn't there a few rc*s ago.

Ack for these 2 patches.

Thanks!