Honestly, I'd do this with a few command-line tools, rather than Perl, but the concepts would be the same:

find Dir_build1 Dir_build2 -type f -size 0 >/tmp/zeros
find Dir_build1 -type f | sort >/tmp/1
find Dir_build2 -type f | sort >/tmp/2
comm -3 /tmp/1 /tmp/2
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To do it in Perl, I'd use File::Find to recursively scan through each directory, adding the file names to an array (probably a hash, actually) for each, then sort and compare the two. During the scans, I'd also build a list of zero-byte files, to avoid scanning through them twice, of course.

use strict;
use warnings;
use File::Find;
find({ wanted => \&process_file, preprocess => \&preprocess, no_chdir 
+=> 1 }, @ARGV);
#find({ wanted => \&process_file, no_chdir => 1 }, @ARGV);
 sub process_file {
@List = ();
if (-f $_) {
 print "This is a file: $_\n";
push(@List,$_);
 } else {
  print "This is not file: $_\n";
 }
return @List;
}
sub preprocess {
 print "pre-processing @_\n";    # never see this
 return sort @_;
}
@DIRLIST = @List;
print "@DIRLIST\n";
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I am trying to return List of Files from File:Find to main Module in @DIRLIST But do not know if it is possible to return a value from wanted sub in File:Find to main sub

Just create your list variable in the main scope of your script, so it'll be in scope inside the sub:

my @list;
find( \&wanted, '.');
say for @list;

sub wanted {
        return unless -f;
        push @list, $File::Find::name;
}
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Google for perl directory file compare, and you will find many pre-written scripts which you can modify. For example, Compare Directories and List Changed or Missing Files