On Sun, Dec 11, 2022 at 11:46:47AM +0900, Masahiro Yamada wrote:
> GNU Make 4.4 introduced $(intcmp ...), which is useful to compare two
> integers without forking a new process.
>
> Add test-{ge,gt,le,lt} macros, which work more efficiently with GNU
> Make >= 4.4. For older Make versions, they fall back to the 'test'
> shell command.
>
> The first two parameters to $(intcmp ...) must not be empty. To avoid
> the syntax error, I appended '0' to them. Fortunately, '00' is treated
> as '0'. This is needed because CONFIG options may expand to an empty
> string when the kernel configuration is not included.
>
> Signed-off-by: Masahiro Yamada <masahiroy@xxxxxxxxxx>
> Acked-by: Palmer Dabbelt <palmer@xxxxxxxxxxxx> # RISC-V
Reviewed-by: Nathan Chancellor <nathan@xxxxxxxxxx>
> ---
>
> Changes in v3:
> - Use $(intcmp ...) instead of playing with $(sort ...)
>
> Makefile | 2 +-
> arch/riscv/Makefile | 2 +-
> arch/x86/Makefile | 2 +-
> scripts/Kbuild.include | 16 ++++++++++++++++
> scripts/Makefile.compiler | 4 ++--
> 5 files changed, 21 insertions(+), 5 deletions(-)
>
> diff --git a/Makefile b/Makefile
> index fbd9ff4a61e7..8801cac4d3d5 100644
> --- a/Makefile
> +++ b/Makefile
> @@ -993,7 +993,7 @@ KBUILD_LDFLAGS += -mllvm -import-instr-limit=5
> # Check for frame size exceeding threshold during prolog/epilog insertion
> # when using lld < 13.0.0.
> ifneq ($(CONFIG_FRAME_WARN),0)
> -ifeq ($(shell test $(CONFIG_LLD_VERSION) -lt 130000; echo $$?),0)
> +ifeq ($(call test-lt, $(CONFIG_LLD_VERSION), 130000),y)
> KBUILD_LDFLAGS += -plugin-opt=-warn-stack-size=$(CONFIG_FRAME_WARN)
> endif
> endif
> diff --git a/arch/riscv/Makefile b/arch/riscv/Makefile
> index 0d13b597cb55..faf2c2177094 100644
> --- a/arch/riscv/Makefile
> +++ b/arch/riscv/Makefile
> @@ -37,7 +37,7 @@ else
> endif
>
> ifeq ($(CONFIG_LD_IS_LLD),y)
> -ifeq ($(shell test $(CONFIG_LLD_VERSION) -lt 150000; echo $$?),0)
> +ifeq ($(call test-lt, $(CONFIG_LLD_VERSION), 150000),y)
> KBUILD_CFLAGS += -mno-relax
> KBUILD_AFLAGS += -mno-relax
> ifndef CONFIG_AS_IS_LLVM
> diff --git a/arch/x86/Makefile b/arch/x86/Makefile
> index 415a5d138de4..e72c7a49cd59 100644
> --- a/arch/x86/Makefile
> +++ b/arch/x86/Makefile
> @@ -211,7 +211,7 @@ endif
> KBUILD_LDFLAGS += -m elf_$(UTS_MACHINE)
>
> ifdef CONFIG_LTO_CLANG
> -ifeq ($(shell test $(CONFIG_LLD_VERSION) -lt 130000; echo $$?),0)
> +ifeq ($(call test-lt, $(CONFIG_LLD_VERSION), 130000),y)
> KBUILD_LDFLAGS += -plugin-opt=-stack-alignment=$(if $(CONFIG_X86_32),4,8)
> endif
> endif
> diff --git a/scripts/Kbuild.include b/scripts/Kbuild.include
> index cbe28744637b..5019bc1e38e4 100644
> --- a/scripts/Kbuild.include
> +++ b/scripts/Kbuild.include
> @@ -11,6 +11,22 @@ space := $(empty) $(empty)
> space_escape := _-_SPACE_-_
> pound := \#
>
> +###
> +# Comparison macros.
> +# Usage: $(call test-lt, $(CONFIG_LLD_VERSION), 150000)
> +#
> +# Use $(intcmp ...) if supported. (Make >= 4.4)
> +# Otherwise, fall back to the 'test' shell command.
> +ifeq ($(intcmp 1,0,,,y),y)
> +test-le = $(intcmp $(strip $1)0, $(strip $2)0,y,y,)
> +test-lt = $(intcmp $(strip $1)0, $(strip $2)0,y,,)
> +else
> +test-le = $(shell test $(strip $1)0 -le $(strip $2)0 && echo y)
> +test-lt = $(shell test $(strip $1)0 -lt $(strip $2)0 && echo y)
> +endif
> +test-ge = $(call test-le, $2, $1)
> +test-gt = $(call test-lt, $2, $1)
> +
> ###
> # Name of target with a '.' as filename prefix. foo/bar.o => foo/.bar.o
> dot-target = $(dir $@).$(notdir $@)
> diff --git a/scripts/Makefile.compiler b/scripts/Makefile.compiler
> index 20d353dcabfb..3d8adfd34af1 100644
> --- a/scripts/Makefile.compiler
> +++ b/scripts/Makefile.compiler
> @@ -63,11 +63,11 @@ cc-disable-warning = $(call try-run,\
>
> # gcc-min-version
> # Usage: cflags-$(call gcc-min-version, 70100) += -foo
> -gcc-min-version = $(shell [ $(CONFIG_GCC_VERSION)0 -ge $(1)0 ] && echo y)
> +gcc-min-version = $(call test-ge, $(CONFIG_GCC_VERSION), $1)
>
> # clang-min-version
> # Usage: cflags-$(call clang-min-version, 110000) += -foo
> -clang-min-version = $(shell [ $(CONFIG_CLANG_VERSION)0 -ge $(1)0 ] && echo y)
> +clang-min-version = $(call test-ge, $(CONFIG_CLANG_VERSION), $1)
>
> # ld-option
> # Usage: KBUILD_LDFLAGS += $(call ld-option, -X, -Y)
> --
> 2.34.1
>
