Re: i386 -> x86_64 cross compile failure (binutils bug?)

Andi Kleen
2005-12-10T07:19:38Z

On Sat, Dec 10, 2005 at 12:12:03AM -0500, Lee Revell wrote:
> On Sat, 2005-12-10 at 01:56 -0700, Andi Kleen wrote:
> > Lee Revell <rlrevell@joe-job.com> writes:
> > > - disable CONFIG_IA32_EMULATION
> >
> > I just tried it here. Adding -m64 to CFLAGS/AFLAGS on a native
> > 64bit biarch toolchain and it compiled without problems. It ends
> > up with -m64 -m32 for the 32bit vsyscall files, but that seems
> > to DTRT at least in gcc 4.
>
> Nope, passing -m64 -m32 does not seem to DTRT on native 32bit biarch
> toolchain:

How about this patch?

-Andi

Pass -m64 by default

This might help on distributions that use a 32bit biarch compiler.

Signed-off-by: Andi Kleen <ak@suse.de>

Index: linux/arch/x86_64/Makefile
===================================================================
--- linux.orig/arch/x86_64/Makefile
+++ linux/arch/x86_64/Makefile
@@ -31,6 +31,7 @@ cflags-$(CONFIG_MK8) += $(call cc-option
cflags-$(CONFIG_MPSC) += $(call cc-option,-march=nocona)
CFLAGS += $(cflags-y)

+CFLAGS += -m64
CFLAGS += -mno-red-zone
CFLAGS += -mcmodel=kernel
CFLAGS += -pipe
@@ -52,6 +53,8 @@ CFLAGS += $(call cc-option,-funit-at-a-t
# prevent gcc from generating any FP code by mistake
CFLAGS += $(call cc-option,-mno-sse -mno-mmx -mno-sse2 -mno-3dnow,)

+AFLAGS += -m64
+
head-y := arch/x86_64/kernel/head.o arch/x86_64/kernel/head64.o arch/x86_64/kernel/init_task.o

libs-y += arch/x86_64/lib/
Index: linux/arch/x86_64/ia32/vsyscall-sigreturn.S
===================================================================
--- linux.orig/arch/x86_64/ia32/vsyscall-sigreturn.S
+++ linux/arch/x86_64/ia32/vsyscall-sigreturn.S
@@ -7,6 +7,7 @@
* by doing ".balign 32" must match in both versions of the page.
*/

+ .code32
.section .text.sigreturn,"ax"
.balign 32
.globl __kernel_sigreturn
Index: linux/arch/x86_64/ia32/vsyscall-syscall.S
===================================================================
--- linux.orig/arch/x86_64/ia32/vsyscall-syscall.S
+++ linux/arch/x86_64/ia32/vsyscall-syscall.S
@@ -6,6 +6,7 @@
#include <asm/asm-offsets.h>
#include <asm/segment.h>

+ .code32
.text
.section .text.vsyscall,"ax"
.globl __kernel_vsyscall
Index: linux/arch/x86_64/ia32/vsyscall-sysenter.S
===================================================================
--- linux.orig/arch/x86_64/ia32/vsyscall-sysenter.S
+++ linux/arch/x86_64/ia32/vsyscall-sysenter.S
@@ -5,6 +5,7 @@
#include <asm/ia32_unistd.h>
#include <asm/asm-offsets.h>

+ .code32
.text
.section .text.vsyscall,"ax"
.globl __kernel_vsyscall