$ cat floog.pl
#!/usr/bin/perl

package Utils;
sub make_hash_table {
    %hash = qw(a,b,c,d);
}

package main;
use Data::Dumper;

Utils::make_hash_table();
print Dumper(\%hash);
print Dumper(\%Utils::hash);
$ perl floog.pl
$VAR1 = {};
$VAR1 = {
          'a,b,c,d' => undef
        };