bug#68808: subsecond mtime discovery code insufficient

    Those square brackets are M4 quotes to prevent M4 from expanding
    $* and $2 itself.

Ah, right. Of course. Good!

The $[*] especially confused me. Just looks so perfectly like an array
reference of some strange kind :). I think it would be a tiny bit
clearer to use $[]*? Or am I missing something again?

More importantly, as far as the make probing goes, I have some other
projects to attend to first. So most likely if you can get to it next
week (fingers crossed for your new machine), that will be sooner than
me. Thanks. -k