As long as it's the results you're after, I wouldn't bother debugging it when a working alternative is so simple to write. 
use File::Find;

push @ARGV, '.' unless @ARGV;

finddepth(sub {
    my $new = lc;
    return if $new eq $_;
    rename $_, $new unless -e $new;
}, @ARGV);

[download]
Using finddepth rather than find is important because directories will otherwise be renamed before File::Find (at that point futily) attempts to recurse into them.

Makeshifts last the longest.

In reply to Re: problems returning from recursive subroutine (file::find instead) by Aristotle
in thread problems returning from recursive subroutine by melguin

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