failures=0

check() {
	if [ "$2" != "$3" ]; then
		echo "Failure at $1" >&2
		failures=$((failures + 1))
	fi
}

check $LINENO "$(trap "echo bye" EXIT; f() { :; }; f >/dev/null)" bye
check $LINENO "$(trap "echo bye" EXIT; f() { :; }; { f; } >/dev/null)" bye
check $LINENO "$(trap "echo bye" EXIT; f() { :; }; (f) >/dev/null)" bye
check $LINENO "$(trap "echo bye" EXIT; f() { :; }; (f >/dev/null))" bye
check $LINENO "$(${SH} -c 'trap "echo bye" EXIT; f() { :; }; f >/dev/null')" bye
check $LINENO "$(${SH} -c 'trap "echo bye" EXIT; f() { :; }; { f; } >/dev/null')" bye
check $LINENO "$(${SH} -c 'trap "echo bye" EXIT; f() { :; }; (f) >/dev/null')" bye
check $LINENO "$(${SH} -c 'trap "echo bye" EXIT; f() { :; }; (f >/dev/null)')" bye

exit $((failures > 0))