[PATCH 0/6] kbuild: strive to avoid $(shell ...) invocations

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* [PATCH 0/6] kbuild: strive to avoid $(shell ...) invocations
@ 2022-11-18 19:53 Masahiro Yamada
  2022-11-18 19:53 ` [PATCH 1/6] kbuild: add test-{le,ge,lt,gt} macros Masahiro Yamada
                   ` (5 more replies)
  0 siblings, 6 replies; 9+ messages in thread
From: Masahiro Yamada @ 2022-11-18 19:53 UTC (permalink / raw)
  To: linux-kbuild; +Cc: linux-kernel, Masahiro Yamada


$(shell ...) forks process(es).
Built-in functions are more efficient.



Masahiro Yamada (6):
  kbuild: add test-{le,ge,lt,gt} macros
  kbuild: make CONFIG_*_VERSION always 6-digit
  kbuild: implement {gcc,clang}-min-version only with built-in functions
  kbuild: add read-file macro
  kconfig: refactor Makefile to reduce process forks
  kbuild: check Make version

 Documentation/kbuild/makefiles.rst          |  6 +--
 Makefile                                    |  9 +++--
 arch/arm/mach-rpc/Kconfig                   |  2 +-
 arch/arm64/Kconfig                          |  4 +-
 arch/mips/vdso/Kconfig                      |  2 +-
 arch/powerpc/Kconfig                        |  2 +-
 arch/riscv/Kconfig                          |  4 +-
 arch/riscv/Makefile                         |  2 +-
 arch/x86/Makefile                           |  2 +-
 drivers/gpu/drm/amd/display/dc/dml/Makefile |  2 +-
 init/Kconfig                                | 18 ++++-----
 lib/Kconfig.debug                           |  6 +--
 lib/Kconfig.kasan                           |  2 +-
 scripts/Kbuild.include                      | 22 +++++++++++
 scripts/Makefile.compiler                   |  6 +--
 scripts/Makefile.modfinal                   |  2 +-
 scripts/Makefile.modinst                    |  2 +-
 scripts/as-version.sh                       |  6 +--
 scripts/cc-version.sh                       |  6 +--
 scripts/kconfig/.gitignore                  |  4 +-
 scripts/kconfig/Makefile                    | 43 +++++++++++----------
 scripts/kconfig/gconf-cfg.sh                |  7 +++-
 scripts/kconfig/mconf-cfg.sh                | 25 ++++++------
 scripts/kconfig/nconf-cfg.sh                | 23 ++++++-----
 scripts/kconfig/qconf-cfg.sh                | 10 +++--
 scripts/ld-version.sh                       |  6 +--
 scripts/remove-stale-files                  |  2 +
 27 files changed, 135 insertions(+), 90 deletions(-)

-- 
2.34.1


^ permalink raw reply	[flat|nested] 9+ messages in thread

* [PATCH 1/6] kbuild: add test-{le,ge,lt,gt} macros
  2022-11-18 19:53 [PATCH 0/6] kbuild: strive to avoid $(shell ...) invocations Masahiro Yamada
@ 2022-11-18 19:53 ` Masahiro Yamada
  2022-11-18 21:07   ` Masahiro Yamada
  2022-11-18 19:53 ` [PATCH 2/6] kbuild: make CONFIG_*_VERSION always 6-digit Masahiro Yamada
                   ` (4 subsequent siblings)
  5 siblings, 1 reply; 9+ messages in thread
From: Masahiro Yamada @ 2022-11-18 19:53 UTC (permalink / raw)
  To: linux-kbuild; +Cc: linux-kernel, Masahiro Yamada

Because GNU Make is only able to handle strings, it is very hard to
perform arighmetic in Makefiles.

When we compare two integers, we invokes shell. One example is in the
top Makefile:

  ifeq ($(shell test $(CONFIG_LLD_VERSION) -lt 130000; echo $$?),0)

This is more expensive than using built-in functions since it forks a
process.

If we know the two have the same number of digits, we can do better.

This commit adds four macros, test-le, test-ge, test-lt, test-gt.

$(call test-lt, A, B) is evaluated to 'y' if A is less than B, or
empty otherwise. This will replace $(call shell test A -lt B).

Again, the limitation is that A and B must have the same number of
digits because these macros are based on $(sort ) function.

  $(call test-lt, 1, 9)    -->  y        (Works!)
  $(call test-lt, 10, 9)   -->  y        (Not work...)

To make the latter work, you need to add '0' prefix to align the number
of digits:

  $(call test-lt, 10, 09)  -->  empty    (Works!)

Actually, we can live with this limitation in many places. As for the
example above, we know $(CONFIG_LLD_VERSION) is 6-digits because the
minimal supported version of LLVM is 11.0.0.

So, the shell invocation can be replaced with more efficient code:

  ifeq ($(call test-lt, $(CONFIG_LLD_VERSION), 130000),y)

Of course, this assumption will break when LLVM 100 is released, but it
will be far in the future.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
---

 Makefile               |  2 +-
 arch/riscv/Makefile    |  2 +-
 arch/x86/Makefile      |  2 +-
 scripts/Kbuild.include | 10 ++++++++++
 4 files changed, 13 insertions(+), 3 deletions(-)

diff --git a/Makefile b/Makefile
index 58cd4f5e1c3a..303516c035f6 100644
--- a/Makefile
+++ b/Makefile
@@ -986,7 +986,7 @@ 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..9996f34327cb 100644
--- a/scripts/Kbuild.include
+++ b/scripts/Kbuild.include
@@ -11,6 +11,16 @@ space   := $(empty) $(empty)
 space_escape := _-_SPACE_-_
 pound := \#
 
+###
+# Comparison macros.
+# Usage: $(call test-le, A, B)
+# works like shell's "test A -le B", but A and B must have the same number of
+# digits since it is just ASCII sort.
+test-le = $(if $(filter $1, $(firstword $(sort $1 $2))),y)
+test-ge = $(call test-le, $2, $1)
+test-lt = $(if $(filter-out $2, $(firstword $(sort $1 $2))),y)
+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 $@)
-- 
2.34.1


^ permalink raw reply related	[flat|nested] 9+ messages in thread

* [PATCH 2/6] kbuild: make CONFIG_*_VERSION always 6-digit
  2022-11-18 19:53 [PATCH 0/6] kbuild: strive to avoid $(shell ...) invocations Masahiro Yamada
  2022-11-18 19:53 ` [PATCH 1/6] kbuild: add test-{le,ge,lt,gt} macros Masahiro Yamada
@ 2022-11-18 19:53 ` Masahiro Yamada
  2022-11-23 15:05   ` Masahiro Yamada
  2022-11-18 19:53 ` [PATCH 3/6] kbuild: implement {gcc,clang}-min-version only with built-in functions Masahiro Yamada
                   ` (3 subsequent siblings)
  5 siblings, 1 reply; 9+ messages in thread
From: Masahiro Yamada @ 2022-11-18 19:53 UTC (permalink / raw)
  To: linux-kbuild; +Cc: linux-kernel, Masahiro Yamada

CONFIG_*_VERSION is the version number of a tool in a 5 or 6-digit form.
This is fine in the Kconfig perspective because Kconfig supports numeric
comparison (<, <=, >, >=).

It is harder in Makefiles due to make's limited numerical capabilities.
So, we ask for shell's "test" command when we compare versions, but it
needs some process forks.

test-{le,ge,lt,gt} macros can compare versions by using only built-in
functions, but the number of digits must be aligned for those macros
to work correctly.

This commit (ab)uses Kconfig's hex type, which allows '0' prefixes,
in order to make CONFIG_*_VERSION always 6-digit.

For example with GCC 9.5, CONFIG_GCC_VERSION=90500 will be turned
into CONFIG_GCC_VERSION=090500.

I touched several Kconfig files so that versions are consistently
compared against 6-digit numbers although this is not mandated.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
---

 arch/arm/mach-rpc/Kconfig |  2 +-
 arch/arm64/Kconfig        |  4 ++--
 arch/mips/vdso/Kconfig    |  2 +-
 arch/powerpc/Kconfig      |  2 +-
 arch/riscv/Kconfig        |  4 ++--
 init/Kconfig              | 18 +++++++++---------
 lib/Kconfig.debug         |  6 +++---
 lib/Kconfig.kasan         |  2 +-
 scripts/as-version.sh     |  6 +++---
 scripts/cc-version.sh     |  6 +++---
 scripts/ld-version.sh     |  6 +++---
 11 files changed, 29 insertions(+), 29 deletions(-)

diff --git a/arch/arm/mach-rpc/Kconfig b/arch/arm/mach-rpc/Kconfig
index 55f6d829b677..106716042308 100644
--- a/arch/arm/mach-rpc/Kconfig
+++ b/arch/arm/mach-rpc/Kconfig
@@ -2,7 +2,7 @@ config ARCH_RPC
 	bool "RiscPC"
 	depends on ARCH_MULTI_V4 && !(ARCH_MULTI_V4T || ARCH_MULTI_V5)
 	depends on !(ARCH_FOOTBRIDGE || ARCH_SA1100 || ARCH_MOXART || ARCH_GEMINI)
-	depends on !CC_IS_CLANG && GCC_VERSION < 90100 && GCC_VERSION >= 60000
+	depends on !CC_IS_CLANG && GCC_VERSION < 090100 && GCC_VERSION >= 060000
 	depends on CPU_LITTLE_ENDIAN
 	depends on ATAGS
 	depends on MMU
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index 505c8a1ccbe0..b318f7ad050b 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -236,7 +236,7 @@ config ARM64
 config CLANG_SUPPORTS_DYNAMIC_FTRACE_WITH_REGS
 	def_bool CC_IS_CLANG
 	# https://github.com/ClangBuiltLinux/linux/issues/1507
-	depends on AS_IS_GNU || (AS_IS_LLVM && (LD_IS_LLD || LD_VERSION >= 23600))
+	depends on AS_IS_GNU || (AS_IS_LLVM && (LD_IS_LLD || LD_VERSION >= 023600))
 	select HAVE_DYNAMIC_FTRACE_WITH_REGS
 
 config GCC_SUPPORTS_DYNAMIC_FTRACE_WITH_REGS
@@ -1814,7 +1814,7 @@ config ARM64_PTR_AUTH_KERNEL
 	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 >= 23301 || (CC_IS_GCC && GCC_VERSION < 90100)
+	depends on LD_IS_LLD || LD_VERSION >= 23301 || (CC_IS_GCC && GCC_VERSION < 090100)
 	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/vdso/Kconfig b/arch/mips/vdso/Kconfig
index a665f6108cb5..a8316108b756 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 >= 22500 || LD_IS_LLD
+	def_bool LD_VERSION >= 022500 || LD_IS_LLD
 
 config MIPS_DISABLE_VDSO
 	def_bool CPU_MICROMIPS || (!CPU_MIPSR6 && !MIPS_LD_CAN_LINK_VDSO)
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 2ca5418457ed..e7ba3a145595 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -220,7 +220,7 @@ config PPC
 	select HAVE_FUNCTION_ERROR_INJECTION
 	select HAVE_FUNCTION_GRAPH_TRACER
 	select HAVE_FUNCTION_TRACER
-	select HAVE_GCC_PLUGINS			if GCC_VERSION >= 50200   # plugin support on gcc <= 5.1 is buggy on PPC
+	select HAVE_GCC_PLUGINS			if GCC_VERSION >= 050200   # plugin support on gcc <= 5.1 is buggy on PPC
 	select HAVE_GENERIC_VDSO
 	select HAVE_HARDLOCKUP_DETECTOR_ARCH	if PPC_BOOK3S_64 && SMP
 	select HAVE_HARDLOCKUP_DETECTOR_PERF	if PERF_EVENTS && HAVE_PERF_EVENTS_NMI && !HAVE_HARDLOCKUP_DETECTOR_ARCH
diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
index fa78595a6089..292f134f4493 100644
--- a/arch/riscv/Kconfig
+++ b/arch/riscv/Kconfig
@@ -416,7 +416,7 @@ config TOOLCHAIN_HAS_ZICBOM
 	default y
 	depends on !64BIT || $(cc-option,-mabi=lp64 -march=rv64ima_zicbom)
 	depends on !32BIT || $(cc-option,-mabi=ilp32 -march=rv32ima_zicbom)
-	depends on LLD_VERSION >= 150000 || LD_VERSION >= 23800
+	depends on LLD_VERSION >= 150000 || LD_VERSION >= 023800
 
 config RISCV_ISA_ZICBOM
 	bool "Zicbom extension support for non-coherent DMA operation"
@@ -440,7 +440,7 @@ config TOOLCHAIN_HAS_ZIHINTPAUSE
 	default y
 	depends on !64BIT || $(cc-option,-mabi=lp64 -march=rv64ima_zihintpause)
 	depends on !32BIT || $(cc-option,-mabi=ilp32 -march=rv32ima_zihintpause)
-	depends on LLD_VERSION >= 150000 || LD_VERSION >= 23600
+	depends on LLD_VERSION >= 150000 || LD_VERSION >= 023600
 
 config FPU
 	bool "FPU support"
diff --git a/init/Kconfig b/init/Kconfig
index abf65098f1b6..402ce28c8eff 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -20,17 +20,17 @@ config CC_IS_GCC
 	def_bool $(success,test "$(cc-name)" = GCC)
 
 config GCC_VERSION
-	int
+	hex
 	default $(cc-version) if CC_IS_GCC
-	default 0
+	default 000000
 
 config CC_IS_CLANG
 	def_bool $(success,test "$(cc-name)" = Clang)
 
 config CLANG_VERSION
-	int
+	hex
 	default $(cc-version) if CC_IS_CLANG
-	default 0
+	default 000000
 
 config AS_IS_GNU
 	def_bool $(success,test "$(as-name)" = GNU)
@@ -39,7 +39,7 @@ config AS_IS_LLVM
 	def_bool $(success,test "$(as-name)" = LLVM)
 
 config AS_VERSION
-	int
+	hex
 	# Use clang version if this is the integrated assembler
 	default CLANG_VERSION if AS_IS_LLVM
 	default $(as-version)
@@ -48,17 +48,17 @@ config LD_IS_BFD
 	def_bool $(success,test "$(ld-name)" = BFD)
 
 config LD_VERSION
-	int
+	hex
 	default $(ld-version) if LD_IS_BFD
-	default 0
+	default 000000
 
 config LD_IS_LLD
 	def_bool $(success,test "$(ld-name)" = LLD)
 
 config LLD_VERSION
-	int
+	hex
 	default $(ld-version) if LD_IS_LLD
-	default 0
+	default 000000
 
 config RUST_IS_AVAILABLE
 	def_bool $(success,$(srctree)/scripts/rust_is_available.sh)
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index d93dbe5a1d14..9d5f061fc4cf 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -258,7 +258,7 @@ config DEBUG_INFO_NONE
 config DEBUG_INFO_DWARF_TOOLCHAIN_DEFAULT
 	bool "Rely on the toolchain's implicit default DWARF version"
 	select DEBUG_INFO
-	depends on !CC_IS_CLANG || AS_IS_LLVM || CLANG_VERSION < 140000 || (AS_IS_GNU && AS_VERSION >= 23502 && AS_HAS_NON_CONST_LEB128)
+	depends on !CC_IS_CLANG || AS_IS_LLVM || CLANG_VERSION < 140000 || (AS_IS_GNU && AS_VERSION >= 023502 && AS_HAS_NON_CONST_LEB128)
 	help
 	  The implicit default version of DWARF debug info produced by a
 	  toolchain changes over time.
@@ -270,7 +270,7 @@ config DEBUG_INFO_DWARF_TOOLCHAIN_DEFAULT
 config DEBUG_INFO_DWARF4
 	bool "Generate DWARF Version 4 debuginfo"
 	select DEBUG_INFO
-	depends on !CC_IS_CLANG || AS_IS_LLVM || (AS_IS_GNU && AS_VERSION >= 23502)
+	depends on !CC_IS_CLANG || AS_IS_LLVM || (AS_IS_GNU && AS_VERSION >= 023502)
 	help
 	  Generate DWARF v4 debug info. This requires gcc 4.5+, binutils 2.35.2
 	  if using clang without clang's integrated assembler, and gdb 7.0+.
@@ -282,7 +282,7 @@ config DEBUG_INFO_DWARF4
 config DEBUG_INFO_DWARF5
 	bool "Generate DWARF Version 5 debuginfo"
 	select DEBUG_INFO
-	depends on !CC_IS_CLANG || AS_IS_LLVM || (AS_IS_GNU && AS_VERSION >= 23502 && AS_HAS_NON_CONST_LEB128)
+	depends on !CC_IS_CLANG || AS_IS_LLVM || (AS_IS_GNU && AS_VERSION >= 023502 && AS_HAS_NON_CONST_LEB128)
 	help
 	  Generate DWARF v5 debug info. Requires binutils 2.35.2, gcc 5.0+ (gcc
 	  5.0+ accepts the -gdwarf-5 flag but only had partial support for some
diff --git a/lib/Kconfig.kasan b/lib/Kconfig.kasan
index ca09b1cf8ee9..2ad969c6eb29 100644
--- a/lib/Kconfig.kasan
+++ b/lib/Kconfig.kasan
@@ -29,7 +29,7 @@ config CC_HAS_KASAN_SW_TAGS
 # Old GCC versions do not have proper support for no_sanitize_address.
 # See https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89124 for details.
 config CC_HAS_WORKING_NOSANITIZE_ADDRESS
-	def_bool !CC_IS_GCC || GCC_VERSION >= 80300
+	def_bool !CC_IS_GCC || GCC_VERSION >= 080300
 
 menuconfig KASAN
 	bool "KASAN: dynamic memory safety error detector"
diff --git a/scripts/as-version.sh b/scripts/as-version.sh
index 1a21495e9ff0..778ccbc82ca8 100755
--- a/scripts/as-version.sh
+++ b/scripts/as-version.sh
@@ -1,14 +1,14 @@
 #!/bin/sh
 # SPDX-License-Identifier: GPL-2.0-only
 #
-# Print the assembler name and its version in a 5 or 6-digit form.
+# Print the assembler name and its version in a 6-digit form.
 # Also, perform the minimum version check.
 # (If it is the integrated assembler, return 0 as the version, and
 # skip the version check.)
 
 set -e
 
-# Convert the version string x.y.z to a canonical 5 or 6-digit form.
+# Convert the version string x.y.z to a canonical 6-digit form.
 get_canonical_version()
 {
 	IFS=.
@@ -18,7 +18,7 @@ get_canonical_version()
 	#
 	# The 4th field, if present, is ignored.
 	# This occurs in development snapshots as in 2.35.1.20201116
-	echo $((10000 * $1 + 100 * ${2:-0} + ${3:-0}))
+	printf "%06d\n" $((10000 * $1 + 100 * ${2:-0} + ${3:-0}))
 }
 
 # Clang fails to handle -Wa,--version unless -fno-integrated-as is given.
diff --git a/scripts/cc-version.sh b/scripts/cc-version.sh
index 2401c86fcf53..fe9f446a40b4 100755
--- a/scripts/cc-version.sh
+++ b/scripts/cc-version.sh
@@ -1,7 +1,7 @@
 #!/bin/sh
 # SPDX-License-Identifier: GPL-2.0
 #
-# Print the C compiler name and its version in a 5 or 6-digit form.
+# Print the C compiler name and its version in a 6-digit form.
 # Also, perform the minimum version check.
 
 set -e
@@ -22,12 +22,12 @@ get_c_compiler_info()
 	EOF
 }
 
-# Convert the version string x.y.z to a canonical 5 or 6-digit form.
+# Convert the version string x.y.z to a canonical 6-digit form.
 get_canonical_version()
 {
 	IFS=.
 	set -- $1
-	echo $((10000 * $1 + 100 * $2 + $3))
+	printf "%06d\n" $((10000 * $1 + 100 * $2 + $3))
 }
 
 # $@ instead of $1 because multiple words might be given, e.g. CC="ccache gcc".
diff --git a/scripts/ld-version.sh b/scripts/ld-version.sh
index a78b804b680c..a00693198a53 100755
--- a/scripts/ld-version.sh
+++ b/scripts/ld-version.sh
@@ -1,12 +1,12 @@
 #!/bin/sh
 # SPDX-License-Identifier: GPL-2.0
 #
-# Print the linker name and its version in a 5 or 6-digit form.
+# Print the linker name and its version in a 6-digit form.
 # Also, perform the minimum version check.
 
 set -e
 
-# Convert the version string x.y.z to a canonical 5 or 6-digit form.
+# Convert the version string x.y.z to a canonical 6-digit form.
 get_canonical_version()
 {
 	IFS=.
@@ -16,7 +16,7 @@ get_canonical_version()
 	#
 	# The 4th field, if present, is ignored.
 	# This occurs in development snapshots as in 2.35.1.20201116
-	echo $((10000 * $1 + 100 * ${2:-0} + ${3:-0}))
+	printf "%06d\n" $((10000 * $1 + 100 * ${2:-0} + ${3:-0}))
 }
 
 orig_args="$@"
-- 
2.34.1


^ permalink raw reply related	[flat|nested] 9+ messages in thread

* [PATCH 3/6] kbuild: implement {gcc,clang}-min-version only with built-in functions
  2022-11-18 19:53 [PATCH 0/6] kbuild: strive to avoid $(shell ...) invocations Masahiro Yamada
  2022-11-18 19:53 ` [PATCH 1/6] kbuild: add test-{le,ge,lt,gt} macros Masahiro Yamada
  2022-11-18 19:53 ` [PATCH 2/6] kbuild: make CONFIG_*_VERSION always 6-digit Masahiro Yamada
@ 2022-11-18 19:53 ` Masahiro Yamada
  2022-11-18 19:53 ` [PATCH 4/6] kbuild: add read-file macro Masahiro Yamada
                   ` (2 subsequent siblings)
  5 siblings, 0 replies; 9+ messages in thread
From: Masahiro Yamada @ 2022-11-18 19:53 UTC (permalink / raw)
  To: linux-kbuild; +Cc: linux-kernel, Masahiro Yamada

Now CONFIG_{GCC,CLANG}_VERSION are always 6-digit, replace the shell
invocations with the test-ge macro.

Please note gcc-min-version must be used against a 6-digit number.
Add '0' prefix.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
---

 Documentation/kbuild/makefiles.rst          | 6 +++---
 Makefile                                    | 2 +-
 drivers/gpu/drm/amd/display/dc/dml/Makefile | 2 +-
 scripts/Makefile.compiler                   | 6 +++---
 4 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/Documentation/kbuild/makefiles.rst b/Documentation/kbuild/makefiles.rst
index 6b7368d1f516..4144f1ce1ab5 100644
--- a/Documentation/kbuild/makefiles.rst
+++ b/Documentation/kbuild/makefiles.rst
@@ -669,18 +669,18 @@ more details, with real examples.
 
     gcc-min-version
 	gcc-min-version tests if the value of $(CONFIG_GCC_VERSION) is greater than
-	or equal to the provided value and evaluates to y if so.
+	or equal to the provided value (in 6-digit form) and evaluates to y if so.
 
 	Example::
 
-		cflags-$(call gcc-min-version, 70100) := -foo
+		cflags-$(call gcc-min-version, 070100) := -foo
 
 	In this example, cflags-y will be assigned the value -foo if $(CC) is gcc and
 	$(CONFIG_GCC_VERSION) is >= 7.1.
 
     clang-min-version
 	clang-min-version tests if the value of $(CONFIG_CLANG_VERSION) is greater
-	than or equal to the provided value and evaluates to y if so.
+	than or equal to the provided value (in 6-digit form) and evaluates to y if so.
 
 	Example::
 
diff --git a/Makefile b/Makefile
index 303516c035f6..03e6ae36c815 100644
--- a/Makefile
+++ b/Makefile
@@ -1050,7 +1050,7 @@ endif
 # ignored, continuing to default to PTRDIFF_MAX. So, left with no other
 # choice, we must perform a versioned check to disable this warning.
 # https://lore.kernel.org/lkml/20210824115859.187f272f@canb.auug.org.au
-KBUILD_CFLAGS-$(call gcc-min-version, 90100) += -Wno-alloc-size-larger-than
+KBUILD_CFLAGS-$(call gcc-min-version, 090100) += -Wno-alloc-size-larger-than
 KBUILD_CFLAGS += $(KBUILD_CFLAGS-y) $(CONFIG_CC_IMPLICIT_FALLTHROUGH)
 
 # disable invalid "can't wrap" optimizations for signed / pointers
diff --git a/drivers/gpu/drm/amd/display/dc/dml/Makefile b/drivers/gpu/drm/amd/display/dc/dml/Makefile
index ca7d24000621..8006801d1b56 100644
--- a/drivers/gpu/drm/amd/display/dc/dml/Makefile
+++ b/drivers/gpu/drm/amd/display/dc/dml/Makefile
@@ -34,7 +34,7 @@ dml_ccflags := -mhard-float -maltivec
 endif
 
 ifdef CONFIG_CC_IS_GCC
-ifneq ($(call gcc-min-version, 70100),y)
+ifneq ($(call gcc-min-version, 070100),y)
 IS_OLD_GCC = 1
 endif
 endif
diff --git a/scripts/Makefile.compiler b/scripts/Makefile.compiler
index 20d353dcabfb..db6f0546b0fc 100644
--- a/scripts/Makefile.compiler
+++ b/scripts/Makefile.compiler
@@ -62,12 +62,12 @@ cc-disable-warning = $(call try-run,\
 	$(CC) -Werror $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) -W$(strip $(1)) -c -x c /dev/null -o "$$TMP",-Wno-$(strip $(1)))
 
 # gcc-min-version
-# Usage: cflags-$(call gcc-min-version, 70100) += -foo
-gcc-min-version = $(shell [ $(CONFIG_GCC_VERSION)0 -ge $(1)0 ] && echo y)
+# Usage: cflags-$(call gcc-min-version, 070100) += -foo
+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


^ permalink raw reply related	[flat|nested] 9+ messages in thread

* [PATCH 4/6] kbuild: add read-file macro
  2022-11-18 19:53 [PATCH 0/6] kbuild: strive to avoid $(shell ...) invocations Masahiro Yamada
                   ` (2 preceding siblings ...)
  2022-11-18 19:53 ` [PATCH 3/6] kbuild: implement {gcc,clang}-min-version only with built-in functions Masahiro Yamada
@ 2022-11-18 19:53 ` Masahiro Yamada
  2022-11-18 19:53 ` [PATCH 5/6] kconfig: refactor Makefile to reduce process forks Masahiro Yamada
  2022-11-18 19:53 ` [PATCH 6/6] kbuild: check Make version Masahiro Yamada
  5 siblings, 0 replies; 9+ messages in thread
From: Masahiro Yamada @ 2022-11-18 19:53 UTC (permalink / raw)
  To: linux-kbuild; +Cc: linux-kernel, Masahiro Yamada

Since GMU Make 4.2, $(file ...) supports the read operater '<', which is
useful to read a file without forking any process. No warning is shown even
if the input file is missing.

For older Make versions, it falls back to the cat command.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
---

 Makefile                  |  2 +-
 scripts/Kbuild.include    | 12 ++++++++++++
 scripts/Makefile.modfinal |  2 +-
 scripts/Makefile.modinst  |  2 +-
 4 files changed, 15 insertions(+), 3 deletions(-)

diff --git a/Makefile b/Makefile
index 03e6ae36c815..93e5749ace55 100644
--- a/Makefile
+++ b/Makefile
@@ -369,7 +369,7 @@ else # !mixed-build
 include $(srctree)/scripts/Kbuild.include
 
 # Read KERNELRELEASE from include/config/kernel.release (if it exists)
-KERNELRELEASE = $(shell cat include/config/kernel.release 2> /dev/null)
+KERNELRELEASE = $(call read-file, include/config/kernel.release)
 KERNELVERSION = $(VERSION)$(if $(PATCHLEVEL),.$(PATCHLEVEL)$(if $(SUBLEVEL),.$(SUBLEVEL)))$(EXTRAVERSION)
 export VERSION PATCHLEVEL SUBLEVEL KERNELRELEASE KERNELVERSION
 
diff --git a/scripts/Kbuild.include b/scripts/Kbuild.include
index 9996f34327cb..722846c23264 100644
--- a/scripts/Kbuild.include
+++ b/scripts/Kbuild.include
@@ -10,6 +10,10 @@ empty   :=
 space   := $(empty) $(empty)
 space_escape := _-_SPACE_-_
 pound := \#
+define newline
+
+
+endef
 
 ###
 # Comparison macros.
@@ -55,6 +59,14 @@ stringify = $(squote)$(quote)$1$(quote)$(squote)
 kbuild-dir = $(if $(filter /%,$(src)),$(src),$(srctree)/$(src))
 kbuild-file = $(or $(wildcard $(kbuild-dir)/Kbuild),$(kbuild-dir)/Makefile)
 
+###
+# Read a file, replacing newlines with spaces
+ifeq ($(call test-ge, $(MAKE_VERSION), 4.2),y)
+read-file = $(subst $(newline),$(space),$(file < $1))
+else
+read-file = $(shell cat $1 2>/dev/null)
+endif
+
 ###
 # Easy method for doing a status message
        kecho := :
diff --git a/scripts/Makefile.modfinal b/scripts/Makefile.modfinal
index 25bedd83644b..7252f6cf7837 100644
--- a/scripts/Makefile.modfinal
+++ b/scripts/Makefile.modfinal
@@ -13,7 +13,7 @@ include $(srctree)/scripts/Kbuild.include
 include $(srctree)/scripts/Makefile.lib
 
 # find all modules listed in modules.order
-modules := $(sort $(shell cat $(MODORDER)))
+modules := $(sort $(call read-file, $(MODORDER)))
 
 __modfinal: $(modules)
 	@:
diff --git a/scripts/Makefile.modinst b/scripts/Makefile.modinst
index a4c987c23750..509d424dbbd2 100644
--- a/scripts/Makefile.modinst
+++ b/scripts/Makefile.modinst
@@ -9,7 +9,7 @@ __modinst:
 include include/config/auto.conf
 include $(srctree)/scripts/Kbuild.include
 
-modules := $(sort $(shell cat $(MODORDER)))
+modules := $(sort $(call read-file, $(MODORDER)))
 
 ifeq ($(KBUILD_EXTMOD),)
 dst := $(MODLIB)/kernel
-- 
2.34.1


^ permalink raw reply related	[flat|nested] 9+ messages in thread

* [PATCH 5/6] kconfig: refactor Makefile to reduce process forks
  2022-11-18 19:53 [PATCH 0/6] kbuild: strive to avoid $(shell ...) invocations Masahiro Yamada
                   ` (3 preceding siblings ...)
  2022-11-18 19:53 ` [PATCH 4/6] kbuild: add read-file macro Masahiro Yamada
@ 2022-11-18 19:53 ` Masahiro Yamada
  2022-11-18 19:53 ` [PATCH 6/6] kbuild: check Make version Masahiro Yamada
  5 siblings, 0 replies; 9+ messages in thread
From: Masahiro Yamada @ 2022-11-18 19:53 UTC (permalink / raw)
  To: linux-kbuild; +Cc: linux-kernel, Masahiro Yamada

Refactor Makefile and use read-file macro. For Make >= 4.2, it can read
out a file by using the built-in function.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
---

 scripts/kconfig/.gitignore   |  4 +++-
 scripts/kconfig/Makefile     | 43 +++++++++++++++++++-----------------
 scripts/kconfig/gconf-cfg.sh |  7 ++++--
 scripts/kconfig/mconf-cfg.sh | 25 ++++++++++++---------
 scripts/kconfig/nconf-cfg.sh | 23 ++++++++++---------
 scripts/kconfig/qconf-cfg.sh | 10 ++++++---
 scripts/remove-stale-files   |  2 ++
 7 files changed, 67 insertions(+), 47 deletions(-)

diff --git a/scripts/kconfig/.gitignore b/scripts/kconfig/.gitignore
index 500e7424b3ef..c8a3f9cd52f0 100644
--- a/scripts/kconfig/.gitignore
+++ b/scripts/kconfig/.gitignore
@@ -1,5 +1,7 @@
 # SPDX-License-Identifier: GPL-2.0-only
 /conf
 /[gmnq]conf
-/[gmnq]conf-cfg
+/[gmnq]conf-cflags
+/[gmnq]conf-libs
+/qconf-bin
 /qconf-moc.cc
diff --git a/scripts/kconfig/Makefile b/scripts/kconfig/Makefile
index b8ef0fb4bbef..da7da9775a4b 100644
--- a/scripts/kconfig/Makefile
+++ b/scripts/kconfig/Makefile
@@ -159,11 +159,12 @@ conf-objs	:= conf.o $(common-objs)
 hostprogs	+= nconf
 nconf-objs	:= nconf.o nconf.gui.o $(common-objs)
 
-HOSTLDLIBS_nconf	= $(shell . $(obj)/nconf-cfg && echo $$libs)
-HOSTCFLAGS_nconf.o	= $(shell . $(obj)/nconf-cfg && echo $$cflags)
-HOSTCFLAGS_nconf.gui.o	= $(shell . $(obj)/nconf-cfg && echo $$cflags)
+HOSTLDLIBS_nconf       = $(call read-file, $(obj)/nconf-libs)
+HOSTCFLAGS_nconf.o     = $(call read-file, $(obj)/nconf-cflags)
+HOSTCFLAGS_nconf.gui.o = $(call read-file, $(obj)/nconf-cflags)
 
-$(obj)/nconf.o $(obj)/nconf.gui.o: $(obj)/nconf-cfg
+$(obj)/nconf: | $(obj)/nconf-libs
+$(obj)/nconf.o $(obj)/nconf.gui.o: | $(obj)/nconf-cflags
 
 # mconf: Used for the menuconfig target based on lxdialog
 hostprogs	+= mconf
@@ -171,27 +172,28 @@ lxdialog	:= $(addprefix lxdialog/, \
 		     checklist.o inputbox.o menubox.o textbox.o util.o yesno.o)
 mconf-objs	:= mconf.o $(lxdialog) $(common-objs)
 
-HOSTLDLIBS_mconf = $(shell . $(obj)/mconf-cfg && echo $$libs)
+HOSTLDLIBS_mconf = $(call read-file, $(obj)/mconf-libs)
 $(foreach f, mconf.o $(lxdialog), \
-  $(eval HOSTCFLAGS_$f = $$(shell . $(obj)/mconf-cfg && echo $$$$cflags)))
+  $(eval HOSTCFLAGS_$f = $$(call read-file, $(obj)/mconf-cflags)))
 
-$(addprefix $(obj)/, mconf.o $(lxdialog)): $(obj)/mconf-cfg
+$(obj)/mconf: | $(obj)/mconf-libs
+$(addprefix $(obj)/, mconf.o $(lxdialog)): | $(obj)/mconf-cflags
 
 # qconf: Used for the xconfig target based on Qt
 hostprogs	+= qconf
 qconf-cxxobjs	:= qconf.o qconf-moc.o
 qconf-objs	:= images.o $(common-objs)
 
-HOSTLDLIBS_qconf	= $(shell . $(obj)/qconf-cfg && echo $$libs)
-HOSTCXXFLAGS_qconf.o	= $(shell . $(obj)/qconf-cfg && echo $$cflags)
-HOSTCXXFLAGS_qconf-moc.o = $(shell . $(obj)/qconf-cfg && echo $$cflags)
-
-$(obj)/qconf.o: $(obj)/qconf-cfg
+HOSTLDLIBS_qconf         = $(call read-file, $(obj)/qconf-libs)
+HOSTCXXFLAGS_qconf.o     = -std=c++11 -fPIC $(call read-file, $(obj)/qconf-cflags)
+HOSTCXXFLAGS_qconf-moc.o = -std=c++11 -fPIC $(call read-file, $(obj)/qconf-cflags)
+$(obj)/qconf: | $(obj)/qconf-libs
+$(obj)/qconf.o $(obj)/qconf-moc.o: | $(obj)/qconf-cflags
 
 quiet_cmd_moc = MOC     $@
-      cmd_moc = $(shell . $(obj)/qconf-cfg && echo $$moc) $< -o $@
+      cmd_moc = $(call read-file, $(obj)/qconf-bin)/moc $< -o $@
 
-$(obj)/qconf-moc.cc: $(src)/qconf.h $(obj)/qconf-cfg FORCE
+$(obj)/qconf-moc.cc: $(src)/qconf.h FORCE | $(obj)/qconf-bin
 	$(call if_changed,moc)
 
 targets += qconf-moc.cc
@@ -200,15 +202,16 @@ targets += qconf-moc.cc
 hostprogs	+= gconf
 gconf-objs	:= gconf.o images.o $(common-objs)
 
-HOSTLDLIBS_gconf    = $(shell . $(obj)/gconf-cfg && echo $$libs)
-HOSTCFLAGS_gconf.o  = $(shell . $(obj)/gconf-cfg && echo $$cflags)
+HOSTLDLIBS_gconf   = $(call read-file, $(obj)/gconf-libs)
+HOSTCFLAGS_gconf.o = $(call read-file, $(obj)/gconf-cflags)
 
-$(obj)/gconf.o: $(obj)/gconf-cfg
+$(obj)/gconf: | $(obj)/gconf-libs
+$(obj)/gconf.o: | $(obj)/gconf-cflags
 
 # check if necessary packages are available, and configure build flags
-filechk_conf_cfg = $(CONFIG_SHELL) $<
+cmd_conf_cfg = $< $(addprefix $(obj)/$*conf-, cflags libs bin)
 
-$(obj)/%conf-cfg: $(src)/%conf-cfg.sh FORCE
-	$(call filechk,conf_cfg)
+$(obj)/%conf-cflags $(obj)/%conf-libs $(obj)/%conf-bin: $(src)/%conf-cfg.sh
+	$(call cmd,conf_cfg)
 
 clean-files += *conf-cfg
diff --git a/scripts/kconfig/gconf-cfg.sh b/scripts/kconfig/gconf-cfg.sh
index cbd90c28c05f..040d8f338820 100755
--- a/scripts/kconfig/gconf-cfg.sh
+++ b/scripts/kconfig/gconf-cfg.sh
@@ -1,6 +1,9 @@
 #!/bin/sh
 # SPDX-License-Identifier: GPL-2.0
 
+cflags=$1
+libs=$2
+
 PKG="gtk+-2.0 gmodule-2.0 libglade-2.0"
 
 if [ -z "$(command -v ${HOSTPKG_CONFIG})" ]; then
@@ -26,5 +29,5 @@ if ! ${HOSTPKG_CONFIG} --atleast-version=2.0.0 gtk+-2.0; then
 	exit 1
 fi
 
-echo cflags=\"$(${HOSTPKG_CONFIG} --cflags $PKG)\"
-echo libs=\"$(${HOSTPKG_CONFIG} --libs $PKG)\"
+${HOSTPKG_CONFIG} --cflags ${PKG} > ${cflags}
+${HOSTPKG_CONFIG} --libs ${PKG} > ${libs}
diff --git a/scripts/kconfig/mconf-cfg.sh b/scripts/kconfig/mconf-cfg.sh
index 025b565e0b7c..1e61f50a5905 100755
--- a/scripts/kconfig/mconf-cfg.sh
+++ b/scripts/kconfig/mconf-cfg.sh
@@ -1,19 +1,22 @@
 #!/bin/sh
 # SPDX-License-Identifier: GPL-2.0
 
+cflags=$1
+libs=$2
+
 PKG="ncursesw"
 PKG2="ncurses"
 
 if [ -n "$(command -v ${HOSTPKG_CONFIG})" ]; then
 	if ${HOSTPKG_CONFIG} --exists $PKG; then
-		echo cflags=\"$(${HOSTPKG_CONFIG} --cflags $PKG)\"
-		echo libs=\"$(${HOSTPKG_CONFIG} --libs $PKG)\"
+		${HOSTPKG_CONFIG} --cflags ${PKG} > ${cflags}
+		${HOSTPKG_CONFIG} --libs ${PKG} > ${libs}
 		exit 0
 	fi
 
-	if ${HOSTPKG_CONFIG} --exists $PKG2; then
-		echo cflags=\"$(${HOSTPKG_CONFIG} --cflags $PKG2)\"
-		echo libs=\"$(${HOSTPKG_CONFIG} --libs $PKG2)\"
+	if ${HOSTPKG_CONFIG} --exists ${PKG2}; then
+		${HOSTPKG_CONFIG} --cflags ${PKG2} > ${cflags}
+		${HOSTPKG_CONFIG} --libs ${PKG2} > ${libs}
 		exit 0
 	fi
 fi
@@ -22,22 +25,22 @@ fi
 # (Even if it is installed, some distributions such as openSUSE cannot
 # find ncurses by pkg-config.)
 if [ -f /usr/include/ncursesw/ncurses.h ]; then
-	echo cflags=\"-D_GNU_SOURCE -I/usr/include/ncursesw\"
-	echo libs=\"-lncursesw\"
+	echo -D_GNU_SOURCE -I/usr/include/ncursesw > ${cflags}
+	echo -lncursesw > ${libs}
 	exit 0
 fi
 
 if [ -f /usr/include/ncurses/ncurses.h ]; then
-	echo cflags=\"-D_GNU_SOURCE -I/usr/include/ncurses\"
-	echo libs=\"-lncurses\"
+	echo -D_GNU_SOURCE -I/usr/include/ncurses > ${cflags}
+	echo -lncurses > ${libs}
 	exit 0
 fi
 
 # As a final fallback before giving up, check if $HOSTCC knows of a default
 # ncurses installation (e.g. from a vendor-specific sysroot).
 if echo '#include <ncurses.h>' | ${HOSTCC} -E - >/dev/null 2>&1; then
-	echo cflags=\"-D_GNU_SOURCE\"
-	echo libs=\"-lncurses\"
+	echo -D_GNU_SOURCE > ${cflags}
+	echo -lncurses > ${libs}
 	exit 0
 fi
 
diff --git a/scripts/kconfig/nconf-cfg.sh b/scripts/kconfig/nconf-cfg.sh
index 3a10bac2adb3..f871a2160e36 100755
--- a/scripts/kconfig/nconf-cfg.sh
+++ b/scripts/kconfig/nconf-cfg.sh
@@ -1,19 +1,22 @@
 #!/bin/sh
 # SPDX-License-Identifier: GPL-2.0
 
+cflags=$1
+libs=$2
+
 PKG="ncursesw menuw panelw"
 PKG2="ncurses menu panel"
 
 if [ -n "$(command -v ${HOSTPKG_CONFIG})" ]; then
 	if ${HOSTPKG_CONFIG} --exists $PKG; then
-		echo cflags=\"$(${HOSTPKG_CONFIG} --cflags $PKG)\"
-		echo libs=\"$(${HOSTPKG_CONFIG} --libs $PKG)\"
+		${HOSTPKG_CONFIG} --cflags ${PKG} > ${cflags}
+		${HOSTPKG_CONFIG} --libs ${PKG} > ${libs}
 		exit 0
 	fi
 
 	if ${HOSTPKG_CONFIG} --exists $PKG2; then
-		echo cflags=\"$(${HOSTPKG_CONFIG} --cflags $PKG2)\"
-		echo libs=\"$(${HOSTPKG_CONFIG} --libs $PKG2)\"
+		${HOSTPKG_CONFIG} --cflags ${PKG2} > ${cflags}
+		${HOSTPKG_CONFIG} --libs ${PKG2} > ${libs}
 		exit 0
 	fi
 fi
@@ -22,20 +25,20 @@ fi
 # (Even if it is installed, some distributions such as openSUSE cannot
 # find ncurses by pkg-config.)
 if [ -f /usr/include/ncursesw/ncurses.h ]; then
-	echo cflags=\"-D_GNU_SOURCE -I/usr/include/ncursesw\"
-	echo libs=\"-lncursesw -lmenuw -lpanelw\"
+	echo -D_GNU_SOURCE -I/usr/include/ncursesw > ${cflags}
+	echo -lncursesw -lmenuw -lpanelw > ${libs}
 	exit 0
 fi
 
 if [ -f /usr/include/ncurses/ncurses.h ]; then
-	echo cflags=\"-D_GNU_SOURCE -I/usr/include/ncurses\"
-	echo libs=\"-lncurses -lmenu -lpanel\"
+	echo -D_GNU_SOURCE -I/usr/include/ncurses > ${cflags}
+	echo -lncurses -lmenu -lpanel > ${libs}
 	exit 0
 fi
 
 if [ -f /usr/include/ncurses.h ]; then
-	echo cflags=\"-D_GNU_SOURCE\"
-	echo libs=\"-lncurses -lmenu -lpanel\"
+	echo -D_GNU_SOURCE > ${cflags}
+	echo -lncurses -lmenu -lpanel > ${libs}
 	exit 0
 fi
 
diff --git a/scripts/kconfig/qconf-cfg.sh b/scripts/kconfig/qconf-cfg.sh
index ad652cb53947..117f36e568fc 100755
--- a/scripts/kconfig/qconf-cfg.sh
+++ b/scripts/kconfig/qconf-cfg.sh
@@ -1,6 +1,10 @@
 #!/bin/sh
 # SPDX-License-Identifier: GPL-2.0
 
+cflags=$1
+libs=$2
+bin=$3
+
 PKG="Qt5Core Qt5Gui Qt5Widgets"
 
 if [ -z "$(command -v ${HOSTPKG_CONFIG})" ]; then
@@ -11,9 +15,9 @@ if [ -z "$(command -v ${HOSTPKG_CONFIG})" ]; then
 fi
 
 if ${HOSTPKG_CONFIG} --exists $PKG; then
-	echo cflags=\"-std=c++11 -fPIC $(${HOSTPKG_CONFIG} --cflags $PKG)\"
-	echo libs=\"$(${HOSTPKG_CONFIG} --libs $PKG)\"
-	echo moc=\"$(${HOSTPKG_CONFIG} --variable=host_bins Qt5Core)/moc\"
+	${HOSTPKG_CONFIG} --cflags ${PKG} > ${cflags}
+	${HOSTPKG_CONFIG} --libs ${PKG} > ${libs}
+	${HOSTPKG_CONFIG} --variable=host_bins Qt5Core > ${bin}
 	exit 0
 fi
 
diff --git a/scripts/remove-stale-files b/scripts/remove-stale-files
index ccadfa3afb2b..64b14aa5aebf 100755
--- a/scripts/remove-stale-files
+++ b/scripts/remove-stale-files
@@ -47,3 +47,5 @@ rm -f arch/riscv/purgatory/kexec-purgatory.c
 rm -f scripts/extract-cert
 
 rm -f arch/x86/purgatory/kexec-purgatory.c
+
+rm -f scripts/kconfig/[gmnq]conf-cfg
-- 
2.34.1


^ permalink raw reply related	[flat|nested] 9+ messages in thread

* [PATCH 6/6] kbuild: check Make version
  2022-11-18 19:53 [PATCH 0/6] kbuild: strive to avoid $(shell ...) invocations Masahiro Yamada
                   ` (4 preceding siblings ...)
  2022-11-18 19:53 ` [PATCH 5/6] kconfig: refactor Makefile to reduce process forks Masahiro Yamada
@ 2022-11-18 19:53 ` Masahiro Yamada
  5 siblings, 0 replies; 9+ messages in thread
From: Masahiro Yamada @ 2022-11-18 19:53 UTC (permalink / raw)
  To: linux-kbuild; +Cc: linux-kernel, Masahiro Yamada

This is implemented based on test-le. It will work until GNU Make 10
is released.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
---

 Makefile | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/Makefile b/Makefile
index 93e5749ace55..979363590bd7 100644
--- a/Makefile
+++ b/Makefile
@@ -368,6 +368,9 @@ else # !mixed-build
 
 include $(srctree)/scripts/Kbuild.include
 
+# Check for the minimal Make version
+$(if $(call test-lt, $(MAKE_VERSION), 3.82), $(error Make $(MAKE_VERSION) is too old))
+
 # Read KERNELRELEASE from include/config/kernel.release (if it exists)
 KERNELRELEASE = $(call read-file, include/config/kernel.release)
 KERNELVERSION = $(VERSION)$(if $(PATCHLEVEL),.$(PATCHLEVEL)$(if $(SUBLEVEL),.$(SUBLEVEL)))$(EXTRAVERSION)
-- 
2.34.1


^ permalink raw reply related	[flat|nested] 9+ messages in thread

* Re: [PATCH 1/6] kbuild: add test-{le,ge,lt,gt} macros
  2022-11-18 19:53 ` [PATCH 1/6] kbuild: add test-{le,ge,lt,gt} macros Masahiro Yamada
@ 2022-11-18 21:07   ` Masahiro Yamada
  0 siblings, 0 replies; 9+ messages in thread
From: Masahiro Yamada @ 2022-11-18 21:07 UTC (permalink / raw)
  To: linux-kbuild; +Cc: linux-kernel

On Sat, Nov 19, 2022 at 4:53 AM Masahiro Yamada <masahiroy@kernel.org> wrote:
>
> Because GNU Make is only able to handle strings, it is very hard to
> perform arighmetic in Makefiles.


arighmetic -> arithmetic


>
> When we compare two integers, we invokes shell. One example is in the


invokes -> invoke



> top Makefile:
>
>   ifeq ($(shell test $(CONFIG_LLD_VERSION) -lt 130000; echo $$?),0)
>
> This is more expensive than using built-in functions since it forks a
> process.
>
> If we know the two have the same number of digits, we can do better.
>
> This commit adds four macros, test-le, test-ge, test-lt, test-gt.
>
> $(call test-lt, A, B) is evaluated to 'y' if A is less than B, or
> empty otherwise. This will replace $(call shell test A -lt B).
>
> Again, the limitation is that A and B must have the same number of
> digits because these macros are based on $(sort ) function.
>
>   $(call test-lt, 1, 9)    -->  y        (Works!)
>   $(call test-lt, 10, 9)   -->  y        (Not work...)
>
> To make the latter work, you need to add '0' prefix to align the number
> of digits:
>
>   $(call test-lt, 10, 09)  -->  empty    (Works!)
>
> Actually, we can live with this limitation in many places. As for the
> example above, we know $(CONFIG_LLD_VERSION) is 6-digits because the
> minimal supported version of LLVM is 11.0.0.
>
> So, the shell invocation can be replaced with more efficient code:
>
>   ifeq ($(call test-lt, $(CONFIG_LLD_VERSION), 130000),y)
>
> Of course, this assumption will break when LLVM 100 is released, but it
> will be far in the future.
>
> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
> ---



-- 
Best Regards
Masahiro Yamada

^ permalink raw reply	[flat|nested] 9+ messages in thread

* Re: [PATCH 2/6] kbuild: make CONFIG_*_VERSION always 6-digit
  2022-11-18 19:53 ` [PATCH 2/6] kbuild: make CONFIG_*_VERSION always 6-digit Masahiro Yamada
@ 2022-11-23 15:05   ` Masahiro Yamada
  0 siblings, 0 replies; 9+ messages in thread
From: Masahiro Yamada @ 2022-11-23 15:05 UTC (permalink / raw)
  To: linux-kbuild; +Cc: linux-kernel

On Sat, Nov 19, 2022 at 4:53 AM Masahiro Yamada <masahiroy@kernel.org> wrote:
>
> CONFIG_*_VERSION is the version number of a tool in a 5 or 6-digit form.
> This is fine in the Kconfig perspective because Kconfig supports numeric
> comparison (<, <=, >, >=).
>
> It is harder in Makefiles due to make's limited numerical capabilities.
> So, we ask for shell's "test" command when we compare versions, but it
> needs some process forks.
>
> test-{le,ge,lt,gt} macros can compare versions by using only built-in
> functions, but the number of digits must be aligned for those macros
> to work correctly.
>
> This commit (ab)uses Kconfig's hex type, which allows '0' prefixes,
> in order to make CONFIG_*_VERSION always 6-digit.
>
> For example with GCC 9.5, CONFIG_GCC_VERSION=90500 will be turned
> into CONFIG_GCC_VERSION=090500.
>
> I touched several Kconfig files so that versions are consistently
> compared against 6-digit numbers although this is not mandated.
>
> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>


I terribly missed that CONFIG_*_VERSION changed the meaning
in C files (decimal -> octal).

I will drop this in V2.



-- 
Best Regards
Masahiro Yamada

^ permalink raw reply	[flat|nested] 9+ messages in thread

end of thread, other threads:[~2022-11-23 15:06 UTC | newest]

Thread overview: 9+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2022-11-18 19:53 [PATCH 0/6] kbuild: strive to avoid $(shell ...) invocations Masahiro Yamada
2022-11-18 19:53 ` [PATCH 1/6] kbuild: add test-{le,ge,lt,gt} macros Masahiro Yamada
2022-11-18 21:07   ` Masahiro Yamada
2022-11-18 19:53 ` [PATCH 2/6] kbuild: make CONFIG_*_VERSION always 6-digit Masahiro Yamada
2022-11-23 15:05   ` Masahiro Yamada
2022-11-18 19:53 ` [PATCH 3/6] kbuild: implement {gcc,clang}-min-version only with built-in functions Masahiro Yamada
2022-11-18 19:53 ` [PATCH 4/6] kbuild: add read-file macro Masahiro Yamada
2022-11-18 19:53 ` [PATCH 5/6] kconfig: refactor Makefile to reduce process forks Masahiro Yamada
2022-11-18 19:53 ` [PATCH 6/6] kbuild: check Make version Masahiro Yamada

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