Re: [PATCH v2] kbuild: add endianness flag to CHEKCFLAGS

From: Masahiro Yamada
Date: Tue May 29 2018 - 09:09:00 EST


2018-05-29 3:27 GMT+09:00 Luc Van Oostenryck <luc.vanoostenryck@xxxxxxxxx>:
> The kernel depends on macros like __BYTE_ORDER__,
> __BIG_ENDIAN__ or __LITTLE_ENDIAN__.
>
> OTOH, sparse doesn't know about the endianness of the kernel and
> by default uses the same as the machine on which sparse was built.
>
> Ensure that sparse can predefine the macros corresponding to
> how the kernel was configured by adding -m{big,little}-endian
> to CHECKFLAGS in the main Makefile (and so for all archs).
> Also, remove the equivalent done in arch specific Makefiles.
>
> Signed-off-by: Luc Van Oostenryck <luc.vanoostenryck@xxxxxxxxx>
> ---


Applied to linux-kbuild. Thanks.


> Makefile | 3 +++
> arch/openrisc/Makefile | 1 -
> arch/parisc/Makefile | 2 +-
> arch/s390/Makefile | 2 +-
> 4 files changed, 5 insertions(+), 3 deletions(-)
>
> diff --git a/Makefile b/Makefile
> index 56ba070df..6c6610913 100644
> --- a/Makefile
> +++ b/Makefile
> @@ -878,6 +878,9 @@ ifeq ($(CONFIG_STRIP_ASM_SYMS),y)
> LDFLAGS_vmlinux += $(call ld-option, -X,)
> endif
>
> +# insure the checker run with the right endianness
> +CHECKFLAGS += $(if $(CONFIG_CPU_BIG_ENDIAN),-mbig-endian,-mlittle-endian)
> +
> # Default kernel image to build when no specific target is given.
> # KBUILD_IMAGE may be overruled on the command line or
> # set in the environment
> diff --git a/arch/openrisc/Makefile b/arch/openrisc/Makefile
> index cf8802962..89076a66e 100644
> --- a/arch/openrisc/Makefile
> +++ b/arch/openrisc/Makefile
> @@ -25,7 +25,6 @@ LDFLAGS_vmlinux :=
> LIBGCC := $(shell $(CC) $(KBUILD_CFLAGS) -print-libgcc-file-name)
>
> KBUILD_CFLAGS += -pipe -ffixed-r10 -D__linux__
> -CHECKFLAGS += -mbig-endian
>
> ifeq ($(CONFIG_OPENRISC_HAVE_INST_MUL),y)
> KBUILD_CFLAGS += $(call cc-option,-mhard-mul)
> diff --git a/arch/parisc/Makefile b/arch/parisc/Makefile
> index 34ac503e2..348ae4779 100644
> --- a/arch/parisc/Makefile
> +++ b/arch/parisc/Makefile
> @@ -22,7 +22,7 @@ KBUILD_IMAGE := vmlinuz
> KBUILD_DEFCONFIG := default_defconfig
>
> NM = sh $(srctree)/arch/parisc/nm
> -CHECKFLAGS += -D__hppa__=1 -mbig-endian
> +CHECKFLAGS += -D__hppa__=1
> LIBGCC = $(shell $(CC) $(KBUILD_CFLAGS) -print-libgcc-file-name)
> export LIBGCC
>
> diff --git a/arch/s390/Makefile b/arch/s390/Makefile
> index c79936d02..68a690442 100644
> --- a/arch/s390/Makefile
> +++ b/arch/s390/Makefile
> @@ -18,7 +18,7 @@ KBUILD_CFLAGS += -m64
> KBUILD_AFLAGS += -m64
> UTS_MACHINE := s390x
> STACK_SIZE := 16384
> -CHECKFLAGS += -D__s390__ -D__s390x__ -mbig-endian
> +CHECKFLAGS += -D__s390__ -D__s390x__
>
> export LD_BFD
>
> --
> 2.17.0
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-kbuild" in
> the body of a message to majordomo@xxxxxxxxxxxxxxx
> More majordomo info at http://vger.kernel.org/majordomo-info.html



--
Best Regards
Masahiro Yamada