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

From: Michael Ellerman <[email-masked]>
Date: Sun, 25 Apr 2021 21:13:15 +1000

Masahiro Yamada <[email-masked]> writes:
> 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 <[email-masked]>
> ---
>
>  arch/powerpc/boot/wrapper                          | 2 +-

Acked-by: Michael Ellerman <[email-masked]> (powerpc)

cheers

>  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