Re: [PATCH v2 1/4] kbuild: use $(CC_VERSION_TEXT) to evaluate CC_IS_GCC and CC_IS_CLANG

From: Masahiro Yamada
Date: Fri May 01 2020 - 01:35:12 EST


On Thu, Apr 23, 2020 at 11:24 PM Masahiro Yamada <masahiroy@xxxxxxxxxx> wrote:
>
> The result of '$(CC) --version | head -n 1' is already computed by the
> top Makefile, and stored in the environment variable, CC_VERSION_TEXT.
>
> 'echo' is probably less expensive than the two commands $(CC) and
> 'head' although this optimization is not noticeable level.
>
> Signed-off-by: Masahiro Yamada <masahiroy@xxxxxxxxxx>

Applied to linux-kbuild.



> ---
>
> Changes in v2:
> - new patch
>
> init/Kconfig | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/init/Kconfig b/init/Kconfig
> index 9e22ee8fbd75..5f797df3f043 100644
> --- a/init/Kconfig
> +++ b/init/Kconfig
> @@ -9,7 +9,7 @@ config DEFCONFIG_LIST
> default "arch/$(SRCARCH)/configs/$(KBUILD_DEFCONFIG)"
>
> config CC_IS_GCC
> - def_bool $(success,$(CC) --version | head -n 1 | grep -q gcc)
> + def_bool $(success,echo "$(CC_VERSION_TEXT)" | grep -q gcc)
>
> config GCC_VERSION
> int
> @@ -21,7 +21,7 @@ config LD_VERSION
> default $(shell,$(LD) --version | $(srctree)/scripts/ld-version.sh)
>
> config CC_IS_CLANG
> - def_bool $(success,$(CC) --version | head -n 1 | grep -q clang)
> + def_bool $(success,echo "$(CC_VERSION_TEXT)" | grep -q clang)
>
> config CLANG_VERSION
> int
> --
> 2.25.1
>
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--
Best Regards
Masahiro Yamada