Hi Julien,
> -----Original Message-----
> From: Julien Grall <jul...@xen.org>
> Sent: 2022年7月1日 20:58
> To: Jan Beulich <jbeul...@suse.com>; Wei Chen <wei.c...@arm.com>
> Cc: Stefano Stabellini <sstabell...@kernel.org>; Bertrand Marquis
> <bertrand.marq...@arm.com>; Volodymyr Babchuk <volodymyr_babc...@epam.com>;
> xen-devel@lists.xenproject.org
> Subject: Re: [PATCH] Xen: fix EFI stub wchar_t size warning of arm32
> building
>
>
>
> On 01/07/2022 11:34, Jan Beulich wrote:
> >> Signed-off-by: Wei Chen <wei.c...@arm.com>
> >> ---
> >> xen/arch/arm/efi/Makefile | 4 ++++
> >> 1 file changed, 4 insertions(+)
> >>
> >> diff --git a/xen/arch/arm/efi/Makefile b/xen/arch/arm/efi/Makefile
> >> index dffe72e589..b06fb96c1f 100644
> >> --- a/xen/arch/arm/efi/Makefile
> >> +++ b/xen/arch/arm/efi/Makefile
> >> @@ -1,5 +1,9 @@
> >> include $(srctree)/common/efi/efi-common.mk
> >>
> >> +ifeq ($(CONFIG_ARM_32),y)
> >> +CFLAGS-y += -fno-short-wchar
> >> +endif
> >
> > Simply
> >
> > CFLAGS-$(CONFIG_ARM_32) += -fno-short-wchar
> >
> > ? But, as suggested, perhaps further
> >
> > $(obj)/stub.o: CFLAGS-$(CONFIG_ARM_32) += -fno-short-wchar
> >
> > to make sure we'd notice any other uses / issues here. After all it
> > is - at least in theory - possible that Arm32 would also gain EFI
> > support, and then it would be a problem if the other ("real") files
> > were compiled that way (albeit I think the issue would be easily
> > noticeable, as I don't think things would build that way).
>
> Instead of CONFIG_ARM_32, I would use CONFIG_ARM_EFI. So this would also
> work if we want to disable EFI on arm64 or enable on arm32.
>
We have already used CONFIG_ARM_EFI to distinguish EFI objects and
stub objects for Arm, so maybe we just need to add
"$(obj)/stub.o: CFLAGS-y += -fno-short-wchar" to:
ifeq ($(CONFIG_ARM_EFI),y)
..
else
...
$(obj)/stub.o: CFLAGS-y += -fno-short-wchar
obj-y += stub.o
endif
Thanks,
Wei Chen
> Cheers,
>
> --
> Julien Grall
