Merge tag 'kbuild-v5.13-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull more Kbuild updates from Masahiro Yamada:

 - Convert sh and sparc to use generic shell scripts to generate the
   syscall headers

 - refactor .gitignore files

 - Update kernel/config_data.gz only when the content of the .config
   is really changed, which avoids the unneeded re-link of vmlinux

 - move "remove stale files" workarounds to scripts/remove-stale-files

 - suppress unused-but-set-variable warnings by default for Clang
   as well

 - fix locale setting LANG=C to LC_ALL=C

 - improve 'make distclean'

 - always keep intermediate objects from scripts/link-vmlinux.sh

 - move IF_ENABLED out of <linux/kconfig.h> to make it self-contained

 - misc cleanups

* tag 'kbuild-v5.13-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (25 commits)
  linux/kconfig.h: replace IF_ENABLED() with PTR_IF() in <linux/kernel.h>
  kbuild: Don't remove link-vmlinux temporary files on exit/signal
  kbuild: remove the unneeded comments for external module builds
  kbuild: make distclean remove tag files in sub-directories
  kbuild: make distclean work against $(objtree) instead of $(srctree)
  kbuild: refactor modname-multi by using suffix-search
  kbuild: refactor fdtoverlay rule
  kbuild: parameterize the .o part of suffix-search
  arch: use cross_compiling to check whether it is a cross build or not
  kbuild: remove ARCH=sh64 support from top Makefile
  .gitignore: prefix local generated files with a slash
  kbuild: replace LANG=C with LC_ALL=C
  Makefile: Move -Wno-unused-but-set-variable out of GCC only block
  kbuild: add a script to remove stale generated files
  kbuild: update config_data.gz only when the content of .config is changed
  .gitignore: ignore only top-level modules.builtin
  .gitignore: move tags and TAGS close to other tag files
  kernel/.gitgnore: remove stale timeconst.h and hz.bc
  usr/include: refactor .gitignore
  genksyms: fix stale comment
  ...

17 files changed, 28 insertions, 196 deletions

diff --git a/arch/.gitignore b/arch/.gitignore
index 4191da401dbbff..756c19c34f99d2 100644
--- a/arch/.gitignore
+++ b/arch/.gitignore
@@ -1,3 +1,3 @@
 # SPDX-License-Identifier: GPL-2.0-only
-i386
-x86_64
+/i386/
+/x86_64/
diff --git a/arch/arm/boot/compressed/Makefile b/arch/arm/boot/compressed/Makefile
index c1f80476862190..8eb70c1febce33 100644
--- a/arch/arm/boot/compressed/Makefile
+++ b/arch/arm/boot/compressed/Makefile
@@ -96,13 +96,6 @@ endif
 $(foreach o, $(libfdt_objs) atags_to_fdt.o fdt_check_mem_start.o, \
 	$(eval CFLAGS_$(o) := -I $(srctree)/scripts/dtc/libfdt -fno-stack-protector))
 
-# These were previously generated C files. When you are building the kernel
-# with O=, make sure to remove the stale files in the output tree. Otherwise,
-# the build system wrongly compiles the stale ones.
-ifdef building_out_of_srctree
-$(shell rm -f $(addprefix $(obj)/, fdt_rw.c fdt_ro.c fdt_wip.c fdt.c))
-endif
-
 targets       := vmlinux vmlinux.lds piggy_data piggy.o \
 		 lib1funcs.o ashldi3.o bswapsdi2.o \
 		 head.o $(OBJS)
diff --git a/arch/m68k/Makefile b/arch/m68k/Makefile
index ea14f2046fb463..82620f14124d29 100644
--- a/arch/m68k/Makefile
+++ b/arch/m68k/Makefile
@@ -16,7 +16,7 @@
 
 KBUILD_DEFCONFIG := multi_defconfig
 
-ifneq ($(SUBARCH),$(ARCH))
+ifdef cross_compiling
 	ifeq ($(CROSS_COMPILE),)
 		CROSS_COMPILE := $(call cc-cross-prefix, \
 			m68k-linux-gnu- m68k-linux- m68k-unknown-linux-gnu-)
diff --git a/arch/mips/Makefile b/arch/mips/Makefile
index e71d587af49c93..258234c35a096d 100644
--- a/arch/mips/Makefile
+++ b/arch/mips/Makefile
@@ -50,7 +50,7 @@ tool-archpref		= $(64bit-tool-archpref)
 UTS_MACHINE		:= mips64
 endif
 
-ifneq ($(SUBARCH),$(ARCH))
+ifdef cross_compiling
   ifeq ($(CROSS_COMPILE),)
     CROSS_COMPILE := $(call cc-cross-prefix, $(tool-archpref)-linux-  $(tool-archpref)-linux-gnu-  $(tool-archpref)-unknown-linux-gnu-)
   endif
diff --git a/arch/parisc/Makefile b/arch/parisc/Makefile
index 7d9f71aa829abb..aed8ea29268bb6 100644
--- a/arch/parisc/Makefile
+++ b/arch/parisc/Makefile
@@ -41,7 +41,7 @@ endif
 
 export LD_BFD
 
-ifneq ($(SUBARCH),$(UTS_MACHINE))
+ifdef cross_compiling
 	ifeq ($(CROSS_COMPILE),)
 		CC_SUFFIXES = linux linux-gnu unknown-linux-gnu
 		CROSS_COMPILE := $(call cc-cross-prefix, \
diff --git a/arch/powerpc/boot/wrapper b/arch/powerpc/boot/wrapper
index 41fa0a8715e3fb..cdb796b76e2eac 100755
--- a/arch/powerpc/boot/wrapper
+++ b/arch/powerpc/boot/wrapper
@@ -191,7 +191,7 @@ if [ -z "$kernel" ]; then
     kernel=vmlinux
 fi
 
-LANG=C elfformat="`${CROSS}objdump -p "$kernel" | grep 'file format' | awk '{print $4}'`"
+LC_ALL=C elfformat="`${CROSS}objdump -p "$kernel" | grep 'file format' | awk '{print $4}'`"
 case "$elfformat" in
     elf64-powerpcle)	format=elf64lppc	;;
     elf64-powerpc)	format=elf32ppc	;;
diff --git a/arch/sh/Makefile b/arch/sh/Makefile
index 3bcbf52fb30eec..44bcb80e791abe 100644
--- a/arch/sh/Makefile
+++ b/arch/sh/Makefile
@@ -9,7 +9,7 @@
 # License.  See the file "COPYING" in the main directory of this archive
 # for more details.
 #
-ifneq ($(SUBARCH),$(ARCH))
+ifdef cross_compiling
   ifeq ($(CROSS_COMPILE),)
     CROSS_COMPILE := $(call cc-cross-prefix, sh-linux- sh-linux-gnu- sh-unknown-linux-gnu-)
   endif
diff --git a/arch/sh/kernel/syscalls/Makefile b/arch/sh/kernel/syscalls/Makefile
index 285aaba832d939..6713c65a25e15c 100644
--- a/arch/sh/kernel/syscalls/Makefile
+++ b/arch/sh/kernel/syscalls/Makefile
@@ -6,20 +6,14 @@ _dummy := $(shell [ -d '$(uapi)' ] || mkdir -p '$(uapi)')	\
 	  $(shell [ -d '$(kapi)' ] || mkdir -p '$(kapi)')
 
 syscall := $(src)/syscall.tbl
-syshdr := $(srctree)/$(src)/syscallhdr.sh
-systbl := $(srctree)/$(src)/syscalltbl.sh
+syshdr := $(srctree)/scripts/syscallhdr.sh
+systbl := $(srctree)/scripts/syscalltbl.sh
 
 quiet_cmd_syshdr = SYSHDR  $@
-      cmd_syshdr = $(CONFIG_SHELL) '$(syshdr)' '$<' '$@'	\
-		   '$(syshdr_abis_$(basetarget))'		\
-		   '$(syshdr_pfx_$(basetarget))'		\
-		   '$(syshdr_offset_$(basetarget))'
+      cmd_syshdr = $(CONFIG_SHELL) $(syshdr) --emit-nr $< $@
 
 quiet_cmd_systbl = SYSTBL  $@
-      cmd_systbl = $(CONFIG_SHELL) '$(systbl)' '$<' '$@'	\
-		   '$(systbl_abis_$(basetarget))'		\
-		   '$(systbl_abi_$(basetarget))'		\
-		   '$(systbl_offset_$(basetarget))'
+      cmd_systbl = $(CONFIG_SHELL) $(systbl) $< $@
 
 $(uapi)/unistd_32.h: $(syscall) $(syshdr) FORCE
 	$(call if_changed,syshdr)
diff --git a/arch/sh/kernel/syscalls/syscallhdr.sh b/arch/sh/kernel/syscalls/syscallhdr.sh
deleted file mode 100644
index 4c0519861e9708..00000000000000
--- a/arch/sh/kernel/syscalls/syscallhdr.sh
+++ /dev/null
@@ -1,36 +0,0 @@
-#!/bin/sh
-# SPDX-License-Identifier: GPL-2.0
-
-in="$1"
-out="$2"
-my_abis=`echo "($3)" | tr ',' '|'`
-prefix="$4"
-offset="$5"
-
-fileguard=_UAPI_ASM_SH_`basename "$out" | sed \
-	-e 'y/abcdefghijklmnopqrstuvwxyz/ABCDEFGHIJKLMNOPQRSTUVWXYZ/' \
-	-e 's/[^A-Z0-9_]/_/g' -e 's/__/_/g'`
-grep -E "^[0-9A-Fa-fXx]+[[:space:]]+${my_abis}" "$in" | sort -n | (
-	printf "#ifndef %s\n" "${fileguard}"
-	printf "#define %s\n" "${fileguard}"
-	printf "\n"
-
-	nxt=0
-	while read nr abi name entry ; do
-		if [ -z "$offset" ]; then
-			printf "#define __NR_%s%s\t%s\n" \
-				"${prefix}" "${name}" "${nr}"
-		else
-			printf "#define __NR_%s%s\t(%s + %s)\n" \
-				"${prefix}" "${name}" "${offset}" "${nr}"
-		fi
-		nxt=$((nr+1))
-	done
-
-	printf "\n"
-	printf "#ifdef __KERNEL__\n"
-	printf "#define __NR_syscalls\t%s\n" "${nxt}"
-	printf "#endif\n"
-	printf "\n"
-	printf "#endif /* %s */\n" "${fileguard}"
-) > "$out"
diff --git a/arch/sh/kernel/syscalls/syscalltbl.sh b/arch/sh/kernel/syscalls/syscalltbl.sh
deleted file mode 100644
index 904b8e6e625d29..00000000000000
--- a/arch/sh/kernel/syscalls/syscalltbl.sh
+++ /dev/null
@@ -1,32 +0,0 @@
-#!/bin/sh
-# SPDX-License-Identifier: GPL-2.0
-
-in="$1"
-out="$2"
-my_abis=`echo "($3)" | tr ',' '|'`
-my_abi="$4"
-offset="$5"
-
-emit() {
-	t_nxt="$1"
-	t_nr="$2"
-	t_entry="$3"
-
-	while [ $t_nxt -lt $t_nr ]; do
-		printf "__SYSCALL(%s,sys_ni_syscall)\n" "${t_nxt}"
-		t_nxt=$((t_nxt+1))
-	done
-	printf "__SYSCALL(%s,%s)\n" "${t_nxt}" "${t_entry}"
-}
-
-grep -E "^[0-9A-Fa-fXx]+[[:space:]]+${my_abis}" "$in" | sort -n | (
-	nxt=0
-	if [ -z "$offset" ]; then
-		offset=0
-	fi
-
-	while read nr abi name entry ; do
-		emit $((nxt+offset)) $((nr+offset)) $entry
-		nxt=$((nr+1))
-	done
-) > "$out"
diff --git a/arch/sparc/include/asm/Kbuild b/arch/sparc/include/asm/Kbuild
index aec20406145e8f..0b9d98ced34aff 100644
--- a/arch/sparc/include/asm/Kbuild
+++ b/arch/sparc/include/asm/Kbuild
@@ -1,7 +1,6 @@
 # SPDX-License-Identifier: GPL-2.0
 generated-y += syscall_table_32.h
 generated-y += syscall_table_64.h
-generated-y += syscall_table_c32.h
 generic-y += export.h
 generic-y += kvm_para.h
 generic-y += mcs_spinlock.h
diff --git a/arch/sparc/kernel/syscalls/Makefile b/arch/sparc/kernel/syscalls/Makefile
index 283f64407b07a4..0f2ea5bcb0d76f 100644
--- a/arch/sparc/kernel/syscalls/Makefile
+++ b/arch/sparc/kernel/syscalls/Makefile
@@ -6,46 +6,34 @@ _dummy := $(shell [ -d '$(uapi)' ] || mkdir -p '$(uapi)')	\
 	  $(shell [ -d '$(kapi)' ] || mkdir -p '$(kapi)')
 
 syscall := $(src)/syscall.tbl
-syshdr := $(srctree)/$(src)/syscallhdr.sh
-systbl := $(srctree)/$(src)/syscalltbl.sh
+syshdr := $(srctree)/scripts/syscallhdr.sh
+systbl := $(srctree)/scripts/syscalltbl.sh
 
 quiet_cmd_syshdr = SYSHDR  $@
-      cmd_syshdr = $(CONFIG_SHELL) '$(syshdr)' '$<' '$@'	\
-		   '$(syshdr_abis_$(basetarget))'		\
-		   '$(syshdr_pfx_$(basetarget))'		\
-		   '$(syshdr_offset_$(basetarget))'
+      cmd_syshdr = $(CONFIG_SHELL) $(syshdr) --emit-nr --abis $(abis) $< $@
 
 quiet_cmd_systbl = SYSTBL  $@
-      cmd_systbl = $(CONFIG_SHELL) '$(systbl)' '$<' '$@'	\
-		   '$(systbl_abis_$(basetarget))'		\
-		   '$(systbl_abi_$(basetarget))'		\
-		   '$(systbl_offset_$(basetarget))'
+      cmd_systbl = $(CONFIG_SHELL) $(systbl) --abis $(abis) $< $@
 
-syshdr_abis_unistd_32 := common,32
+$(uapi)/unistd_32.h: abis := common,32
 $(uapi)/unistd_32.h: $(syscall) $(syshdr) FORCE
 	$(call if_changed,syshdr)
 
-syshdr_abis_unistd_64 := common,64
+$(uapi)/unistd_64.h: abis := common,64
 $(uapi)/unistd_64.h: $(syscall) $(syshdr) FORCE
 	$(call if_changed,syshdr)
 
-systbl_abis_syscall_table_32 := common,32
+$(kapi)/syscall_table_32.h: abis := common,32
 $(kapi)/syscall_table_32.h: $(syscall) $(systbl) FORCE
 	$(call if_changed,systbl)
 
-systbl_abis_syscall_table_64 := common,64
+$(kapi)/syscall_table_64.h: abis := common,64
 $(kapi)/syscall_table_64.h: $(syscall) $(systbl) FORCE
 	$(call if_changed,systbl)
 
-systbl_abis_syscall_table_c32 := common,32
-systbl_abi_syscall_table_c32 := c32
-$(kapi)/syscall_table_c32.h: $(syscall) $(systbl) FORCE
-	$(call if_changed,systbl)
-
 uapisyshdr-y		+= unistd_32.h unistd_64.h
 kapisyshdr-y		+= syscall_table_32.h		\
-			   syscall_table_64.h		\
-			   syscall_table_c32.h
+			   syscall_table_64.h
 
 uapisyshdr-y	:= $(addprefix $(uapi)/, $(uapisyshdr-y))
 kapisyshdr-y	:= $(addprefix $(kapi)/, $(kapisyshdr-y))
diff --git a/arch/sparc/kernel/syscalls/syscallhdr.sh b/arch/sparc/kernel/syscalls/syscallhdr.sh
deleted file mode 100644
index cf50a75cc0bb28..00000000000000
--- a/arch/sparc/kernel/syscalls/syscallhdr.sh
+++ /dev/null
@@ -1,36 +0,0 @@
-#!/bin/sh
-# SPDX-License-Identifier: GPL-2.0
-
-in="$1"
-out="$2"
-my_abis=`echo "($3)" | tr ',' '|'`
-prefix="$4"
-offset="$5"
-
-fileguard=_UAPI_ASM_SPARC_`basename "$out" | sed \
-	-e 'y/abcdefghijklmnopqrstuvwxyz/ABCDEFGHIJKLMNOPQRSTUVWXYZ/' \
-	-e 's/[^A-Z0-9_]/_/g' -e 's/__/_/g'`
-grep -E "^[0-9A-Fa-fXx]+[[:space:]]+${my_abis}" "$in" | sort -n | (
-	printf "#ifndef %s\n" "${fileguard}"
-	printf "#define %s\n" "${fileguard}"
-	printf "\n"
-
-	nxt=0
-	while read nr abi name entry compat ; do
-		if [ -z "$offset" ]; then
-			printf "#define __NR_%s%s\t%s\n" \
-				"${prefix}" "${name}" "${nr}"
-		else
-			printf "#define __NR_%s%s\t(%s + %s)\n" \
-				"${prefix}" "${name}" "${offset}" "${nr}"
-		fi
-		nxt=$((nr+1))
-	done
-
-	printf "\n"
-	printf "#ifdef __KERNEL__\n"
-	printf "#define __NR_syscalls\t%s\n" "${nxt}"
-	printf "#endif\n"
-	printf "\n"
-	printf "#endif /* %s */\n" "${fileguard}"
-) > "$out"
diff --git a/arch/sparc/kernel/syscalls/syscalltbl.sh b/arch/sparc/kernel/syscalls/syscalltbl.sh
deleted file mode 100644
index 77cf0143ba1969..00000000000000
--- a/arch/sparc/kernel/syscalls/syscalltbl.sh
+++ /dev/null
@@ -1,36 +0,0 @@
-#!/bin/sh
-# SPDX-License-Identifier: GPL-2.0
-
-in="$1"
-out="$2"
-my_abis=`echo "($3)" | tr ',' '|'`
-my_abi="$4"
-offset="$5"
-
-emit() {
-	t_nxt="$1"
-	t_nr="$2"
-	t_entry="$3"
-
-	while [ $t_nxt -lt $t_nr ]; do
-		printf "__SYSCALL(%s, sys_nis_syscall, )\n" "${t_nxt}"
-		t_nxt=$((t_nxt+1))
-	done
-	printf "__SYSCALL(%s, %s, )\n" "${t_nxt}" "${t_entry}"
-}
-
-grep -E "^[0-9A-Fa-fXx]+[[:space:]]+${my_abis}" "$in" | sort -n | (
-	nxt=0
-	if [ -z "$offset" ]; then
-		offset=0
-	fi
-
-	while read nr abi name entry compat ; do
-		if [ "$my_abi" = "c32" ] && [ ! -z "$compat" ]; then
-			emit $((nxt+offset)) $((nr+offset)) $compat
-		else
-			emit $((nxt+offset)) $((nr+offset)) $entry
-		fi
-		nxt=$((nr+1))
-	done
-) > "$out"
diff --git a/arch/sparc/kernel/systbls_32.S b/arch/sparc/kernel/systbls_32.S
index ab9e4d57685a9d..3aaffa017706b0 100644
--- a/arch/sparc/kernel/systbls_32.S
+++ b/arch/sparc/kernel/systbls_32.S
@@ -9,10 +9,10 @@
  * Copyright (C) 1995 Adrian M. Rodriguez (adrian@remus.rutgers.edu)
  */
 
-#define __SYSCALL(nr, entry, nargs) .long entry
+#define __SYSCALL_WITH_COMPAT(nr, native, compat)	__SYSCALL(nr, native)
+#define __SYSCALL(nr, entry) .long entry
 	.data
 	.align 4
 	.globl sys_call_table
 sys_call_table:
 #include <asm/syscall_table_32.h>	/* 32-bit native syscalls */
-#undef __SYSCALL
diff --git a/arch/sparc/kernel/systbls_64.S b/arch/sparc/kernel/systbls_64.S
index a27394bf7d7f63..398fe449dd34b5 100644
--- a/arch/sparc/kernel/systbls_64.S
+++ b/arch/sparc/kernel/systbls_64.S
@@ -10,18 +10,20 @@
  * Copyright (C) 1995 Adrian M. Rodriguez (adrian@remus.rutgers.edu)
  */
 
-#define __SYSCALL(nr, entry, nargs) .word entry
+#define __SYSCALL(nr, entry) .word entry
 	.text
 	.align	4
 #ifdef CONFIG_COMPAT
 	.globl sys_call_table32
 sys_call_table32:
-#include <asm/syscall_table_c32.h>	/* Compat syscalls */
+#define __SYSCALL_WITH_COMPAT(nr, native, compat)	__SYSCALL(nr, compat)
+#include <asm/syscall_table_32.h>	/* Compat syscalls */
+#undef __SYSCALL_WITH_COMPAT
 #endif /* CONFIG_COMPAT */
 
 	.align	4
 	.globl sys_call_table64, sys_call_table
 sys_call_table64:
 sys_call_table:
+#define __SYSCALL_WITH_COMPAT(nr, native, compat)	__SYSCALL(nr, native)
 #include <asm/syscall_table_64.h>	/* 64-bit native syscalls */
-#undef __SYSCALL
diff --git a/arch/xtensa/Makefile b/arch/xtensa/Makefile
index ba9fee75e67547..e9c8f064c44d0d 100644
--- a/arch/xtensa/Makefile
+++ b/arch/xtensa/Makefile
@@ -19,12 +19,8 @@ variant-y := $(patsubst "%",%,$(CONFIG_XTENSA_VARIANT_NAME))
 VARIANT = $(variant-y)
 export VARIANT
 
-# Test for cross compiling
-
 ifneq ($(VARIANT),)
-  COMPILE_ARCH = $(shell uname -m)
-
-  ifneq ($(COMPILE_ARCH), xtensa)
+  ifdef cross_compiling
     ifndef CROSS_COMPILE
       CROSS_COMPILE = xtensa_$(VARIANT)-
     endif