You've got your $end commented out (update: your example runs fine when it's not). :) Use strict and warnings. It'll save you much trouble. Also, tracking an index in this situation is a bit artificial. You're already destroying the array so just use that as your end point (the existence of elements in the array).

use warnings;
use strict;
my @array= ( 1 .. 9 );

while ( @array ) {
    my $last = pop @array;
    print "$last\n";
}

# ...or...
my @array= ( 1 .. 9 );
print "$_\n" while $_ = pop @array;
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