two kinds of order

[積丹尼 Dan Jacobson]

On (info "(make) Automatic Variables")
please mention which of

M:/dev/null /dev/zero
        : $?
        : $+
        : $^
        : $|

are guaranteed to preserve the order. I.e.,
/dev/null /dev/zero not
/dev/zero /dev/null.
and which all bets are off.

Also maybe when people read about
(Info-index "order-only prerequisites")
mention also there is also a second kind of order,
the kind I mention above.