Can anyone understand why the two lists output by this test program are different? Note the first word of both lists.

Update: Added the references to the outputs to show they hadn't changed.

Update2: This code won't do anything useful before 5.8.3.

#! perl -slw
use strict;

my $s = 'the quick brown fox jumps over the lazy dog';

my @wordRefs;

print do{ 
    my $ref = \substr( $s, $-[ 0 ], $+[ 1 ] - $-[ 0 ] );
    push @wordRefs, $ref;
    "$ref : $$ref";
} while $s =~ m[(\S+\s*)]g;

print $/, '---', $/;

print "$_ : $$_" for @wordRefs;

__END__
P:\test>subrefs
LVALUE(0x182caf8) : the
LVALUE(0x1831624) : quick
LVALUE(0x18315d0) : brown
LVALUE(0x1824334) : fox
LVALUE(0x18243f4) : jumps
LVALUE(0x1831660) : over
LVALUE(0x1831678) : the
LVALUE(0x1831690) : lazy
LVALUE(0x18316a8) : dog

---

LVALUE(0x182caf8) : dog
LVALUE(0x1831624) : quick
LVALUE(0x18315d0) : brown
LVALUE(0x1824334) : fox
LVALUE(0x18243f4) : jumps
LVALUE(0x1831660) : over
LVALUE(0x1831678) : the
LVALUE(0x1831690) : lazy
LVALUE(0x18316a8) : dog
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The first list is produced as the references are stacked. The second is produced from those same references. Why are they different?