Re: [RFC PATCH 2/2] kbuild: Rename and use BINUTILS_VERSION where needed

[Masahiro Yamada]

On Sun, Apr 19, 2020 at 10:21 PM Sedat Dilek <sedat.dilek@xxxxxxxxx> wrote:
>
> In the first patch I introduced LD_IS_BINUTILS Kconfig.
>
> To be consistent in naming convention I renamed from LD_VERSION
> to BINUTILS_VERSION.
>
> So, we have the double "LD_IS_BINUTILS" and "BINUTILS_VERSION"
> like "CC_IS_GCC" and "GCC_VERSION".
>
> For the same reason I renamed the shell script to detect the GNU ld
> linker version.
>
> In Documentation/process/changes.rst we use "binutils" and GNU ld
> binary is part of it (see [3]).
>
> The patches "init/kconfig: Add LD_VERSION Kconfig" (see [1]) and
> "arm64: Kconfig: ptrauth: Add binutils version check to fix mismatch"
> (see [2]) added checks for binutils >=2.23.1 whereas binutils
> version 2.23 is minimum supported version (see [3]).
>
> I have renamed to BINUTILS_VERSION where needed.



I do not think this is the right thing to do.

As the doc implies
https://lore.kernel.org/lkml/20200224174129.2664-1-ndesaulniers@xxxxxxxxxx/T/
we support overriding CC, LD, ... etc. individually.
(such a usage might be rare with LLVM=1 syntax supported, though)



I'd rather want to stick to LD_VERSION
instead of the version of the tool suite.



config BINUTILS_VERSION
       int
       default $(shell,$(LD) --version |
$(srctree)/scripts/binutils-version.sh) if LD_IS_BINUTILS


This will leave BINUTILS_VERSION empty when LD=ld.lld,
but it looks strange if binutils is still used for other tools.




>
> [1] https://git.kernel.org/linus/9553d16fa671b9621c5e2847d08bd90d3be3349c
> [2] https://git.kernel.org/linus/15cd0e675f3f76b4d21c313795fe0c23df0ee20f
> [3] https://git.kernel.org/linus/Documentation/process/changes.rst#n79
>
> Signed-off-by: Sedat Dilek <sedat.dilek@xxxxxxxxx>
> ---
>  arch/arm64/Kconfig                             | 2 +-
>  init/Kconfig                                   | 4 ++--
>  scripts/{ld-version.sh => binutils-version.sh} | 0
>  3 files changed, 3 insertions(+), 3 deletions(-)
>  rename scripts/{ld-version.sh => binutils-version.sh} (100%)
>
> diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
> index 40fb05d96c60..274ba9b3ac95 100644
> --- a/arch/arm64/Kconfig
> +++ b/arch/arm64/Kconfig
> @@ -1504,7 +1504,7 @@ config ARM64_PTR_AUTH
>         depends on (CC_HAS_SIGN_RETURN_ADDRESS || CC_HAS_BRANCH_PROT_PAC_RET) && AS_HAS_PAC
>         # GCC 9.1 and later inserts a .note.gnu.property section note for PAC
>         # which is only understood by binutils starting with version 2.33.1.
> -       depends on !CC_IS_GCC || GCC_VERSION < 90100 || LD_VERSION >= 233010000
> +       depends on !CC_IS_GCC || GCC_VERSION < 90100 || BINUTILS_VERSION >= 233010000
>         depends on !CC_IS_CLANG || AS_HAS_CFI_NEGATE_RA_STATE
>         depends on (!FUNCTION_GRAPH_TRACER || DYNAMIC_FTRACE_WITH_REGS)
>         help
> diff --git a/init/Kconfig b/init/Kconfig
> index 520116efea0f..946db4786951 100644
> --- a/init/Kconfig
> +++ b/init/Kconfig
> @@ -19,9 +19,9 @@ config GCC_VERSION
>  config LD_IS_BINUTILS
>         def_bool $(success,$(LD) -v | head -n 1 | grep -q 'GNU ld')
>
> -config LD_VERSION
> +config BINUTILS_VERSION
>         int
> -       default $(shell,$(LD) --version | $(srctree)/scripts/ld-version.sh) if LD_IS_BINUTILS
> +       default $(shell,$(LD) --version | $(srctree)/scripts/binutils-version.sh) if LD_IS_BINUTILS
>
>  config CC_IS_CLANG
>         def_bool $(success,$(CC) --version | head -n 1 | grep -q clang)
> diff --git a/scripts/ld-version.sh b/scripts/binutils-version.sh
> similarity index 100%
> rename from scripts/ld-version.sh
> rename to scripts/binutils-version.sh
> --
> 2.26.1
>


-- 
Best Regards
Masahiro Yamada