Re: [PATCH] kbuild: replace LANG=C with LC_ALL=C

[Matthias Maennich <maennich@google.com>]

On Sat, Apr 24, 2021 at 08:48:41PM +0900, Masahiro Yamada wrote:
>LANG gives a weak default to each LC_* in case it is not explicitly
>defined. LC_ALL, if set, overrides all other LC_* variables.
>
>  LANG  <  LC_CTYPE, LC_COLLATE, LC_MONETARY, LC_NUMERIC, ...  <  LC_ALL
>
>This is why documentation such as [1] suggests to set LC_ALL in build
>scripts to get the deterministic result.
>
>LANG=C is not strong enough to override LC_* that may be set by end
>users.
>
>[1]: https://reproducible-builds.org/docs/locales/
>
>Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

Reviewed-by: Matthias Maennich <maennich@google.com>

Cheers,
Matthias

>---
>
> arch/powerpc/boot/wrapper                          | 2 +-
> scripts/nsdeps                                     | 2 +-
> scripts/recordmcount.pl                            | 2 +-
> scripts/setlocalversion                            | 2 +-
> scripts/tags.sh                                    | 2 +-
> tools/testing/selftests/net/mptcp/mptcp_connect.sh | 2 +-
> usr/gen_initramfs.sh                               | 2 +-
> 7 files changed, 7 insertions(+), 7 deletions(-)
>
>diff --git a/arch/powerpc/boot/wrapper b/arch/powerpc/boot/wrapper
>index 41fa0a8715e3..cdb796b76e2e 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/scripts/nsdeps b/scripts/nsdeps
>index e8ce2a4d704a..04c4b96e95ec 100644
>--- a/scripts/nsdeps
>+++ b/scripts/nsdeps
>@@ -44,7 +44,7 @@ generate_deps() {
> 		for source_file in $mod_source_files; do
> 			sed '/MODULE_IMPORT_NS/Q' $source_file > ${source_file}.tmp
> 			offset=$(wc -l ${source_file}.tmp | awk '{print $1;}')
>-			cat $source_file | grep MODULE_IMPORT_NS | LANG=C sort -u >> ${source_file}.tmp
>+			cat $source_file | grep MODULE_IMPORT_NS | LC_ALL=C sort -u >> ${source_file}.tmp
> 			tail -n +$((offset +1)) ${source_file} | grep -v MODULE_IMPORT_NS >> ${source_file}.tmp
> 			if ! diff -q ${source_file} ${source_file}.tmp; then
> 				mv ${source_file}.tmp ${source_file}
>diff --git a/scripts/recordmcount.pl b/scripts/recordmcount.pl
>index 867860ea57da..0a7fc9507d6f 100755
>--- a/scripts/recordmcount.pl
>+++ b/scripts/recordmcount.pl
>@@ -497,7 +497,7 @@ sub update_funcs
> #
> # Step 2: find the sections and mcount call sites
> #
>-open(IN, "LANG=C $objdump -hdr $inputfile|") || die "error running $objdump";
>+open(IN, "LC_ALL=C $objdump -hdr $inputfile|") || die "error running $objdump";
>
> my $text;
>
>diff --git a/scripts/setlocalversion b/scripts/setlocalversion
>index bb709eda96cd..db941f6d9591 100755
>--- a/scripts/setlocalversion
>+++ b/scripts/setlocalversion
>@@ -126,7 +126,7 @@ scm_version()
> 	fi
>
> 	# Check for svn and a svn repo.
>-	if rev=$(LANG= LC_ALL= LC_MESSAGES=C svn info 2>/dev/null | grep '^Last Changed Rev'); then
>+	if rev=$(LC_ALL=C svn info 2>/dev/null | grep '^Last Changed Rev'); then
> 		rev=$(echo $rev | awk '{print $NF}')
> 		printf -- '-svn%s' "$rev"
>
>diff --git a/scripts/tags.sh b/scripts/tags.sh
>index fd96734deff1..db8ba411860a 100755
>--- a/scripts/tags.sh
>+++ b/scripts/tags.sh
>@@ -326,5 +326,5 @@ esac
>
> # Remove structure forward declarations.
> if [ -n "$remove_structs" ]; then
>-    LANG=C sed -i -e '/^\([a-zA-Z_][a-zA-Z0-9_]*\)\t.*\t\/\^struct \1;.*\$\/;"\tx$/d' $1
>+    LC_ALL=C sed -i -e '/^\([a-zA-Z_][a-zA-Z0-9_]*\)\t.*\t\/\^struct \1;.*\$\/;"\tx$/d' $1
> fi
>diff --git a/tools/testing/selftests/net/mptcp/mptcp_connect.sh b/tools/testing/selftests/net/mptcp/mptcp_connect.sh
>index 10a030b53b23..1d2a6e7b877c 100755
>--- a/tools/testing/selftests/net/mptcp/mptcp_connect.sh
>+++ b/tools/testing/selftests/net/mptcp/mptcp_connect.sh
>@@ -273,7 +273,7 @@ check_mptcp_disabled()
> 	ip netns exec ${disabled_ns} sysctl -q net.mptcp.enabled=0
>
> 	local err=0
>-	LANG=C ip netns exec ${disabled_ns} ./mptcp_connect -t $timeout -p 10000 -s MPTCP 127.0.0.1 < "$cin" 2>&1 | \
>+	LC_ALL=C ip netns exec ${disabled_ns} ./mptcp_connect -t $timeout -p 10000 -s MPTCP 127.0.0.1 < "$cin" 2>&1 | \
> 		grep -q "^socket: Protocol not available$" && err=1
> 	ip netns delete ${disabled_ns}
>
>diff --git a/usr/gen_initramfs.sh b/usr/gen_initramfs.sh
>index 8ae831657e5d..63476bb70b41 100755
>--- a/usr/gen_initramfs.sh
>+++ b/usr/gen_initramfs.sh
>@@ -147,7 +147,7 @@ dir_filelist() {
> 	header "$1"
>
> 	srcdir=$(echo "$1" | sed -e 's://*:/:g')
>-	dirlist=$(find "${srcdir}" -printf "%p %m %U %G\n" | LANG=C sort)
>+	dirlist=$(find "${srcdir}" -printf "%p %m %U %G\n" | LC_ALL=C sort)
>
> 	# If $dirlist is only one line, then the directory is empty
> 	if [  "$(echo "${dirlist}" | wc -l)" -gt 1 ]; then
>-- 
>2.27.0
>