The scanner warns every file on  Slim::Schema::_preCheckAttributes (2469) Warning: Use of each().

The code is potentially incorrect and can result in unwanted results. 

It can easily be corrected with :

2469,2470c2469
<       foreach my $key (keys($attributes)) {
---
>       while (my ($key, $val) = each %$attributes) {


It would also be a bit faster as the value is not needed in the loop.