Re: [PATCH 2/3] kbuild: LD_VERSION redenomination

[Masahiro Yamada]

On Sun, Dec 13, 2020 at 1:54 AM Masahiro Yamada <masahiroy@xxxxxxxxxx> wrote:
>
> Commit ccbef1674a15 ("Kbuild, lto: add ld-version and ld-ifversion
> macros") introduced scripts/ld-version.sh for GCC LTO.
>
> At that time, this script handled 5 version fields because GCC LTO
> needed the downstream binutils. (https://lkml.org/lkml/2014/4/8/272)
>
> The code snippet from the submitted patch was as follows:
>
>     # We need HJ Lu's Linux binutils because mainline binutils does not
>     # support mixing assembler and LTO code in the same ld -r object.
>     # XXX check if the gcc plugin ld is the expected one too
>     # XXX some Fedora binutils should also support it. How to check for that?
>     ifeq ($(call ld-ifversion,-ge,22710001,y),y)
>         ...
>
> However, GCC LTO was not merged into the mainline after all.
> (https://lkml.org/lkml/2014/4/8/272)
>
> So, the 4th and 5th fields were never used, and finally removed by
> commit 0d61ed17dd30 ("ld-version: Drop the 4th and 5th version
> components").
>
> Since then, the last 4-digits returned by this script is always zeros.
>
> Remove the meaningless last 4-digits. This makes the version format
> consistent with GCC_VERSION, CLANG_VERSION, LLD_VERSION.
>
> Signed-off-by: Masahiro Yamada <masahiroy@xxxxxxxxxx>
> ---
>

Applied to linux-kbuild.


>  arch/arm64/Kconfig            | 2 +-
>  arch/mips/loongson64/Platform | 2 +-
>  arch/mips/vdso/Kconfig        | 2 +-
>  arch/powerpc/Makefile         | 2 +-
>  arch/powerpc/lib/Makefile     | 2 +-
>  scripts/ld-version.sh         | 2 +-
>  6 files changed, 6 insertions(+), 6 deletions(-)
>
> diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
> index a6b5b7ef40ae..69d56b21a6ec 100644
> --- a/arch/arm64/Kconfig
> +++ b/arch/arm64/Kconfig
> @@ -1499,7 +1499,7 @@ config ARM64_PTR_AUTH
>         depends on (CC_HAS_SIGN_RETURN_ADDRESS || CC_HAS_BRANCH_PROT_PAC_RET) && AS_HAS_PAC
>         # Modern compilers insert a .note.gnu.property section note for PAC
>         # which is only understood by binutils starting with version 2.33.1.
> -       depends on LD_IS_LLD || LD_VERSION >= 233010000 || (CC_IS_GCC && GCC_VERSION < 90100)
> +       depends on LD_IS_LLD || LD_VERSION >= 23301 || (CC_IS_GCC && GCC_VERSION < 90100)
>         depends on !CC_IS_CLANG || AS_HAS_CFI_NEGATE_RA_STATE
>         depends on (!FUNCTION_GRAPH_TRACER || DYNAMIC_FTRACE_WITH_REGS)
>         help
> diff --git a/arch/mips/loongson64/Platform b/arch/mips/loongson64/Platform
> index ec42c5085905..cc0b9c87f9ad 100644
> --- a/arch/mips/loongson64/Platform
> +++ b/arch/mips/loongson64/Platform
> @@ -35,7 +35,7 @@ cflags-$(CONFIG_CPU_LOONGSON64)       += $(call as-option,-Wa$(comma)-mno-fix-loongson
>  # can't easily be used safely within the kbuild framework.
>  #
>  ifeq ($(call cc-ifversion, -ge, 0409, y), y)
> -  ifeq ($(call ld-ifversion, -ge, 225000000, y), y)
> +  ifeq ($(call ld-ifversion, -ge, 22500, y), y)
>      cflags-$(CONFIG_CPU_LOONGSON64)  += \
>        $(call cc-option,-march=loongson3a -U_MIPS_ISA -D_MIPS_ISA=_MIPS_ISA_MIPS64)
>    else
> diff --git a/arch/mips/vdso/Kconfig b/arch/mips/vdso/Kconfig
> index 7aec721398d5..a665f6108cb5 100644
> --- a/arch/mips/vdso/Kconfig
> +++ b/arch/mips/vdso/Kconfig
> @@ -12,7 +12,7 @@
>  # the lack of relocations. As such, we disable the VDSO for microMIPS builds.
>
>  config MIPS_LD_CAN_LINK_VDSO
> -       def_bool LD_VERSION >= 225000000 || LD_IS_LLD
> +       def_bool LD_VERSION >= 22500 || LD_IS_LLD
>
>  config MIPS_DISABLE_VDSO
>         def_bool CPU_MICROMIPS || (!CPU_MIPSR6 && !MIPS_LD_CAN_LINK_VDSO)
> diff --git a/arch/powerpc/Makefile b/arch/powerpc/Makefile
> index 5c8c06215dd4..6a9a852c3d56 100644
> --- a/arch/powerpc/Makefile
> +++ b/arch/powerpc/Makefile
> @@ -65,7 +65,7 @@ UTS_MACHINE := $(subst $(space),,$(machine-y))
>  ifdef CONFIG_PPC32
>  KBUILD_LDFLAGS_MODULE += arch/powerpc/lib/crtsavres.o
>  else
> -ifeq ($(call ld-ifversion, -ge, 225000000, y),y)
> +ifeq ($(call ld-ifversion, -ge, 22500, y),y)
>  # Have the linker provide sfpr if possible.
>  # There is a corresponding test in arch/powerpc/lib/Makefile
>  KBUILD_LDFLAGS_MODULE += --save-restore-funcs
> diff --git a/arch/powerpc/lib/Makefile b/arch/powerpc/lib/Makefile
> index 69a91b571845..d4efc182662a 100644
> --- a/arch/powerpc/lib/Makefile
> +++ b/arch/powerpc/lib/Makefile
> @@ -31,7 +31,7 @@ obj-$(CONFIG_FUNCTION_ERROR_INJECTION)        += error-inject.o
>  # 64-bit linker creates .sfpr on demand for final link (vmlinux),
>  # so it is only needed for modules, and only for older linkers which
>  # do not support --save-restore-funcs
> -ifeq ($(call ld-ifversion, -lt, 225000000, y),y)
> +ifeq ($(call ld-ifversion, -lt, 22500, y),y)
>  extra-$(CONFIG_PPC64)  += crtsavres.o
>  endif
>
> diff --git a/scripts/ld-version.sh b/scripts/ld-version.sh
> index f2be0ff9a738..0f8a2c0f9502 100755
> --- a/scripts/ld-version.sh
> +++ b/scripts/ld-version.sh
> @@ -6,6 +6,6 @@
>         gsub(".*version ", "");
>         gsub("-.*", "");
>         split($1,a, ".");
> -       print a[1]*100000000 + a[2]*1000000 + a[3]*10000;
> +       print a[1]*10000 + a[2]*100 + a[3];
>         exit
>         }
> --
> 2.27.0
>


-- 
Best Regards
Masahiro Yamada