On one machine (Scientific Linux 6.9, Perl v5.10.1) I get plenty of warnings such as "Use of uninitialized value $xyz..." but the very same script gives me no warnings on another machine (Ubuntu 16.04, Perl v5.22.1). I copied it over with scp. Both copies of the same script start with: 
use strict;
use warnings;

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Does anyone have any idea what might be causing this?

In reply to Warnings not working on one machine by questions

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