Aha! we see a difference between 5.6.0 and 5.6.1 with respect to this: 
D:\Perl56\bin>perl -MO=Deparse -we "$x=[];for($i=0;$i<=$#x;$i++){}"
$x = [];
$i = 0;
while ($i <= $#x) {
    ();
}
continue {
    ++$i
}
-e syntax OK

D:\>perl -MO=Deparse -we "$x=[];for($i=0;$i<=$#x;$i++){}"
$x = [];
for ($i = 0; $i <= $#x; ++$i) {
    ();
}
-e syntax OK

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Here I tried to compare 5.6.0 (I called it from 5.6.0 dir which is d:\perl56\bin in my computer) and 5.6.1 (it's in my $PATH)

update I did update to call a snippet without compile errors; but explanation of results before and after update are same

In reply to Re: (jeffa) 3Re: Is for(@$array_ref) construct optimized? YES! by Weasel
in thread Is for(@$array_ref) construct optimized? YES! by Weasel

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