Use of uninitialized value in split at foo.pl line 9.

##</code><code>##

Use of uninitialized value in split at foo.pl line 9.
0
Use of uninitialized value in pattern match (m//) at foo.pl line 14.
0

##</code><code>##

#!/usr/bin/perl

use strict;
use warnings;
use Benchmark qw(:all :hireswallclock);

my $str="This is an example string with several words bla bla bla";

sub test1 () {
    local $_=$str;
    my $entries = @{[ split ]};
}

sub test2 () {
    local $_=$str;
    my $entries = () = /\S+/g;
}

cmpthese -10, {
    deref => \&test1,
    goatse => \&test2,
};

__END__

##</code><code>##

          Rate goatse  deref
goatse 16325/s     --   -42%
deref  28017/s    72%     --