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 $(CC) and 'head' although this optimization is not noticeable level. Signed-off-by: Masahiro Yamada <masahiroy@xxxxxxxxxx> --- Changes in v2: - new patch init/Kconfig | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/init/Kconfig b/init/Kconfig index 9e22ee8fbd75..5f797df3f043 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -9,7 +9,7 @@ config DEFCONFIG_LIST default "arch/$(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