kbuild: remove ar-option and KBUILD_ARFLAGS

Commit 40df759e2b9e ("kbuild: Fix build with binutils <= 2.19")
introduced ar-option and KBUILD_ARFLAGS to cope with old binutils.

According to Documentation/process/changes.rst, the current minimal
supported version of binutils is 2.21 so you can assume the 'D' option
is always supported. Not only GNU ar but also llvm-ar supports it.

With the 'D' option hard-coded, there is no more user of ar-option
or KBUILD_ARFLAGS.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

---

 Documentation/kbuild/makefiles.rst | 5 -----
 Makefile                           | 4 ----
 arch/powerpc/boot/Makefile         | 2 +-
 scripts/Kbuild.include             | 5 -----
 scripts/Makefile.build             | 2 +-
 scripts/Makefile.lib               | 2 +-
 6 files changed, 3 insertions(+), 17 deletions(-)

-- 
2.17.1

On Tue, Sep 24, 2019 at 9:38 AM Masahiro Yamada
<yamada.masahiro@socionext.com> wrote:
>

> Commit 40df759e2b9e ("kbuild: Fix build with binutils <= 2.19")

> introduced ar-option and KBUILD_ARFLAGS to cope with old binutils.

>

> According to Documentation/process/changes.rst, the current minimal

> supported version of binutils is 2.21 so you can assume the 'D' option

> is always supported. Not only GNU ar but also llvm-ar supports it.


Yep, a nice cleanup. Thanks for the patch and I appreciate checking llvm-ar.
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>

Tested-by: Nick Desaulniers <ndesaulniers@google.com>


>

> With the 'D' option hard-coded, there is no more user of ar-option

> or KBUILD_ARFLAGS.

>

> Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

> ---

>

>  Documentation/kbuild/makefiles.rst | 5 -----

>  Makefile                           | 4 ----

>  arch/powerpc/boot/Makefile         | 2 +-

>  scripts/Kbuild.include             | 5 -----

>  scripts/Makefile.build             | 2 +-

>  scripts/Makefile.lib               | 2 +-

>  6 files changed, 3 insertions(+), 17 deletions(-)

>

> diff --git a/Documentation/kbuild/makefiles.rst b/Documentation/kbuild/makefiles.rst

> index 6ba9d5365ff3..b89c88168d6a 100644

> --- a/Documentation/kbuild/makefiles.rst

> +++ b/Documentation/kbuild/makefiles.rst

> @@ -954,11 +954,6 @@ When kbuild executes, the following steps are followed (roughly):

>

>         From commandline LDFLAGS_MODULE shall be used (see kbuild.txt).

>

> -    KBUILD_ARFLAGS   Options for $(AR) when creating archives

> -

> -       $(KBUILD_ARFLAGS) set by the top level Makefile to "D" (deterministic

> -       mode) if this option is supported by $(AR).

> -

>      KBUILD_LDS

>

>         The linker script with full path. Assigned by the top-level Makefile.

> diff --git a/Makefile b/Makefile

> index 656a8c95789d..88b180b2cb64 100644

> --- a/Makefile

> +++ b/Makefile

> @@ -498,7 +498,6 @@ export CFLAGS_KASAN CFLAGS_KASAN_NOSANITIZE CFLAGS_UBSAN

>  export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE

>  export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_LDFLAGS_MODULE

>  export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL

> -export KBUILD_ARFLAGS

>

>  # Files to ignore in find ... statements

>

> @@ -914,9 +913,6 @@ ifdef CONFIG_RETPOLINE

>  KBUILD_CFLAGS += $(call cc-option,-fcf-protection=none)

>  endif

>

> -# use the deterministic mode of AR if available

> -KBUILD_ARFLAGS := $(call ar-option,D)

> -

>  include scripts/Makefile.kasan

>  include scripts/Makefile.extrawarn

>  include scripts/Makefile.ubsan

> diff --git a/arch/powerpc/boot/Makefile b/arch/powerpc/boot/Makefile

> index 6841bd52738b..dfbd7f22eef5 100644

> --- a/arch/powerpc/boot/Makefile

> +++ b/arch/powerpc/boot/Makefile

> @@ -50,7 +50,7 @@ endif

>

>  BOOTAFLAGS     := -D__ASSEMBLY__ $(BOOTCFLAGS) -nostdinc

>

> -BOOTARFLAGS    := -cr$(KBUILD_ARFLAGS)

> +BOOTARFLAGS    := -crD

>

>  ifdef CONFIG_CC_IS_CLANG

>  BOOTCFLAGS += $(CLANG_FLAGS)

> diff --git a/scripts/Kbuild.include b/scripts/Kbuild.include

> index e31fd6a8b2a3..956668239ef5 100644

> --- a/scripts/Kbuild.include

> +++ b/scripts/Kbuild.include

> @@ -143,11 +143,6 @@ cc-ifversion = $(shell [ $(CONFIG_GCC_VERSION)0 $(1) $(2)000 ] && echo $(3) || e

>  # Usage: KBUILD_LDFLAGS += $(call ld-option, -X, -Y)

>  ld-option = $(call try-run, $(LD) $(KBUILD_LDFLAGS) $(1) -v,$(1),$(2),$(3))

>

> -# ar-option

> -# Usage: KBUILD_ARFLAGS := $(call ar-option,D)

> -# Important: no spaces around options

> -ar-option = $(call try-run, $(AR) rc$(1) "$$TMP",$(1),$(2))

> -

>  # ld-version

>  # Note this is mainly for HJ Lu's 3 number binutil versions

>  ld-version = $(shell $(LD) --version | $(srctree)/scripts/ld-version.sh)

> diff --git a/scripts/Makefile.build b/scripts/Makefile.build

> index 611bda95ac5e..f199341f04eb 100644

> --- a/scripts/Makefile.build

> +++ b/scripts/Makefile.build

> @@ -395,7 +395,7 @@ $(sort $(subdir-obj-y)): $(subdir-ym) ;

>  ifdef builtin-target

>

>  quiet_cmd_ar_builtin = AR      $@

> -      cmd_ar_builtin = rm -f $@; $(AR) rcSTP$(KBUILD_ARFLAGS) $@ $(real-prereqs)

> +      cmd_ar_builtin = rm -f $@; $(AR) cDPrST $@ $(real-prereqs)

>

>  $(builtin-target): $(real-obj-y) FORCE

>         $(call if_changed,ar_builtin)

> diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib

> index 23e524027740..15895fd4ef9f 100644

> --- a/scripts/Makefile.lib

> +++ b/scripts/Makefile.lib

> @@ -238,7 +238,7 @@ quiet_cmd_ld = LD      $@

>  # ---------------------------------------------------------------------------

>

>  quiet_cmd_ar = AR      $@

> -      cmd_ar = rm -f $@; $(AR) rcsTP$(KBUILD_ARFLAGS) $@ $(real-prereqs)

> +      cmd_ar = rm -f $@; $(AR) cDPrsT $@ $(real-prereqs)

>

>  # Objcopy

>  # ---------------------------------------------------------------------------

> --

> 2.17.1

>

> --

> You received this message because you are subscribed to the Google Groups "Clang Built Linux" group.

> To unsubscribe from this group and stop receiving emails from it, send an email to clang-built-linux+unsubscribe@googlegroups.com.

> To view this discussion on the web visit https://groups.google.com/d/msgid/clang-built-linux/20190921064954.11196-1-yamada.masahiro%40socionext.com.




-- 
Thanks,
~Nick Desaulniers