Commit b753101a authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge tag 'kbuild-v5.7-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild 

Pull more Kbuild updates from Masahiro Yamada:

 - raise minimum supported binutils version to 2.23

 - remove old CONFIG_AS_* macros that we know binutils >= 2.23 supports

 - move remaining CONFIG_AS_* tests to Kconfig from Makefile

 - enable -Wtautological-compare warnings to catch more issues

 - do not support GCC plugins for GCC <= 4.7

 - fix various breakages of 'make xconfig'

 - include the linker version used for linking the kernel into
   LINUX_COMPILER, which is used for the banner, and also exposed to
   /proc/version

 - link lib-y objects to vmlinux forcibly when CONFIG_MODULES=y, which
   allows us to remove the lib-ksyms.o workaround, and to solve the last
   known issue of the LLVM linker

 - add dummy tools in scripts/dummy-tools/ to enable all compiler tests
   in Kconfig, which will be useful for distro maintainers

 - support the single switch, LLVM=1 to use Clang and all LLVM utilities
   instead of GCC and Binutils.

 - support LLVM_IAS=1 to enable the integrated assembler, which is still
   experimental

* tag 'kbuild-v5.7-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (36 commits)
  kbuild: fix comment about missing include guard detection
  kbuild: support LLVM=1 to switch the default tools to Clang/LLVM
  kbuild: replace AS=clang with LLVM_IAS=1
  kbuild: add dummy toolchains to enable all cc-option etc. in Kconfig
  kbuild: link lib-y objects to vmlinux forcibly when CONFIG_MODULES=y
  MIPS: fw: arc: add __weak to prom_meminit and prom_free_prom_memory
  kbuild: remove -I$(srctree)/tools/include from scripts/Makefile
  kbuild: do not pass $(KBUILD_CFLAGS) to scripts/mkcompile_h
  Documentation/llvm: fix the name of llvm-size
  kbuild: mkcompile_h: Include $LD version in /proc/version
  kconfig: qconf: Fix a few alignment issues
  kconfig: qconf: remove some old bogus TODOs
  kconfig: qconf: fix support for the split view mode
  kconfig: qconf: fix the content of the main widget
  kconfig: qconf: Change title for the item window
  kconfig: qconf: clean deprecated warnings
  gcc-plugins: drop support for GCC <= 4.7
  kbuild: Enable -Wtautological-compare
  x86: update AS_* macros to binutils >=2.23, supporting ADX and AVX2
  crypto: x86 - clean up poly1305-x86_64-cryptogams.S by 'make clean'
  ...
parents c7850ae4 00d76a0c

Documentation/kbuild/kbuild.rst

+5 −0
Original line number Diff line number Diff line
@@ -262,3 +262,8 @@ KBUILD_BUILD_USER, KBUILD_BUILD_HOST 
These two variables allow to override the user@host string displayed during

boot and in /proc/version. The default value is the output of the commands

whoami and host, respectively.



LLVM

----

If this variable is set to 1, Kbuild will use Clang and LLVM utilities instead

of GCC and GNU binutils to build the kernel.

Documentation/kbuild/llvm.rst

+11 −4
Original line number Diff line number Diff line
@@ -47,14 +47,21 @@ example: 
LLVM Utilities

--------------



LLVM has substitutes for GNU binutils utilities. These can be invoked as

additional parameters to `make`.

LLVM has substitutes for GNU binutils utilities. Kbuild supports `LLVM=1`

to enable them.



	make CC=clang AS=clang LD=ld.lld AR=llvm-ar NM=llvm-nm STRIP=llvm-strip \\

	  OBJCOPY=llvm-objcopy OBJDUMP=llvm-objdump OBJSIZE=llvm-objsize \\

	make LLVM=1



They can be enabled individually. The full list of the parameters:



	make CC=clang LD=ld.lld AR=llvm-ar NM=llvm-nm STRIP=llvm-strip \\

	  OBJCOPY=llvm-objcopy OBJDUMP=llvm-objdump OBJSIZE=llvm-size \\

	  READELF=llvm-readelf HOSTCC=clang HOSTCXX=clang++ HOSTAR=llvm-ar \\

	  HOSTLD=ld.lld



Currently, the integrated assembler is disabled by default. You can pass

`LLVM_IAS=1` to enable it.



Getting Help

------------

Documentation/process/changes.rst

+2 −2
Original line number Diff line number Diff line
@@ -31,7 +31,7 @@ you probably needn't concern yourself with pcmciautils. 
====================== ===============  ========================================

GNU C                  4.6              gcc --version

GNU make               3.81             make --version

binutils               2.21             ld -v

binutils               2.23             ld -v

flex                   2.5.35           flex --version

bison                  2.0              bison --version

util-linux             2.10o            fdformat --version
@@ -76,7 +76,7 @@ You will need GNU make 3.81 or later to build the kernel. 
Binutils

--------



Binutils 2.21 or newer is needed to build the kernel.

Binutils 2.23 or newer is needed to build the kernel.



pkg-config

----------

Makefile

+30 −10
Original line number Diff line number Diff line
@@ -399,8 +399,13 @@ HOST_LFS_CFLAGS := $(shell getconf LFS_CFLAGS 2>/dev/null) 
HOST_LFS_LDFLAGS := $(shell getconf LFS_LDFLAGS 2>/dev/null)

HOST_LFS_LIBS := $(shell getconf LFS_LIBS 2>/dev/null)



ifneq ($(LLVM),)

HOSTCC	= clang

HOSTCXX	= clang++

else

HOSTCC	= gcc

HOSTCXX	= g++

endif

KBUILD_HOSTCFLAGS   := -Wall -Wmissing-prototypes -Wstrict-prototypes -O2 \

		-fomit-frame-pointer -std=gnu89 $(HOST_LFS_CFLAGS) \

		$(HOSTCFLAGS)
@@ -409,16 +414,28 @@ KBUILD_HOSTLDFLAGS := $(HOST_LFS_LDFLAGS) $(HOSTLDFLAGS) 
KBUILD_HOSTLDLIBS   := $(HOST_LFS_LIBS) $(HOSTLDLIBS)



# Make variables (CC, etc...)

LD		= $(CROSS_COMPILE)ld

CC		= $(CROSS_COMPILE)gcc

CPP		= $(CC) -E

ifneq ($(LLVM),)

CC		= clang

LD		= ld.lld

AR		= llvm-ar

NM		= llvm-nm

OBJCOPY		= llvm-objcopy

OBJDUMP		= llvm-objdump

READELF		= llvm-readelf

OBJSIZE		= llvm-size

STRIP		= llvm-strip

else

CC		= $(CROSS_COMPILE)gcc

LD		= $(CROSS_COMPILE)ld

AR		= $(CROSS_COMPILE)ar

NM		= $(CROSS_COMPILE)nm

STRIP		= $(CROSS_COMPILE)strip

OBJCOPY		= $(CROSS_COMPILE)objcopy

OBJDUMP		= $(CROSS_COMPILE)objdump

OBJSIZE		= $(CROSS_COMPILE)size

READELF		= $(CROSS_COMPILE)readelf

OBJSIZE		= $(CROSS_COMPILE)size

STRIP		= $(CROSS_COMPILE)strip

endif

PAHOLE		= pahole

LEX		= flex

YACC		= bison
@@ -538,7 +555,7 @@ endif 
ifneq ($(GCC_TOOLCHAIN),)

CLANG_FLAGS	+= --gcc-toolchain=$(GCC_TOOLCHAIN)

endif

ifeq ($(if $(AS),$(shell $(AS) --version 2>&1 | head -n 1 | grep clang)),)

ifneq ($(LLVM_IAS),1)

CLANG_FLAGS	+= -no-integrated-as

endif

CLANG_FLAGS	+= -Werror=unknown-warning-option
@@ -747,8 +764,6 @@ ifdef CONFIG_CC_IS_CLANG 
KBUILD_CPPFLAGS += -Qunused-arguments

KBUILD_CFLAGS += -Wno-format-invalid-specifier

KBUILD_CFLAGS += -Wno-gnu

# Quiet clang warning: comparison of unsigned expression < 0 is always false

KBUILD_CFLAGS += -Wno-tautological-compare

# CLANG uses a _MergedGlobals as optimization, but this breaks modpost, as the

# source of a reference will be _MergedGlobals and not on of the whitelisted names.

# See modpost pattern 2
@@ -1036,8 +1051,13 @@ init-y := $(patsubst %/, %/built-in.a, $(init-y)) 
core-y		:= $(patsubst %/, %/built-in.a, $(core-y))

drivers-y	:= $(patsubst %/, %/built-in.a, $(drivers-y))

net-y		:= $(patsubst %/, %/built-in.a, $(net-y))

libs-y2		:= $(patsubst %/, %/built-in.a, $(filter %/, $(libs-y)))

ifdef CONFIG_MODULES

libs-y1		:= $(filter-out %/, $(libs-y))

libs-y2		+= $(patsubst %/, %/lib.a, $(filter %/, $(libs-y)))

else

libs-y1		:= $(patsubst %/, %/lib.a, $(libs-y))

libs-y2		:= $(patsubst %/, %/built-in.a, $(filter-out %.a, $(libs-y)))

endif

virt-y		:= $(patsubst %/, %/built-in.a, $(virt-y))



# Externally visible symbols (used by link-vmlinux.sh)

arch/h8300/include/uapi/asm/bitsperlong.h→arch/h8300/include/uapi/asm/posix_types.h

+13 −0
Original line number Diff line number Diff line 
/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */

#ifndef _UAPI__ASM_H8300_BITS_PER_LONG

#define _UAPI__ASM_H8300_BITS_PER_LONG

/* SPDX-License-Identifier: GPL-2.0-only WITH Linux-syscall-note */

#ifndef _UAPI_ASM_POSIX_TYPES_H

#define _UAPI_ASM_POSIX_TYPES_H



#include <asm-generic/bitsperlong.h>



#if !defined(__ASSEMBLY__)

/* h8300-unknown-linux required long */

#define __kernel_size_t __kernel_size_t

typedef unsigned long	__kernel_size_t;

typedef long		__kernel_ssize_t;

typedef long		__kernel_ptrdiff_t;

#endif



#endif /* _UAPI__ASM_H8300_BITS_PER_LONG */
 
#include <asm-generic/posix_types.h>



#endif /* _UAPI_ASM_POSIX_TYPES_H */