IFS=,

SPECIAL="break,\
	:,\
	continue,\
	. /dev/null,\
	eval,\
	exec,\
	export -p,\
	readonly -p,\
	set,\
	shift,\
	times,\
	trap,\
	unset foo"

# If there is no command word, the shell must abort on an assignment error.
${SH} -c "readonly a=0; a=2; exit 0" 2>/dev/null && exit 1

# Special built-in utilities must abort on an assignment error.
set -- ${SPECIAL}
for cmd in "$@"
do
	${SH} -c "readonly a=0; a=2 ${cmd}; exit 0" 2>/dev/null && exit 1
done

# Other utilities must not abort; we currently still execute them.
${SH} -c 'readonly a=0; a=1 true; exit $a' 2>/dev/null || exit 1
${SH} -c 'readonly a=0; a=1 command :; exit $a' 2>/dev/null || exit 1