Sometimes, using a newer version of Perl helps. E.g. 

use strict;
use warnings;

my $x = "";
my $y;
my $z = "Z";

if ($x =~ /X/ or $y =~ /Y/ or $z =~ /Z/) {
    print "cond true\n"
}

[download]

Perl 5.8.8 

$ ./669664.pl
Use of uninitialized value in pattern match (m//) at ./669664.pl line 10.
cond true

Perl 5.10.0 

$ ./669664.pl
Use of uninitialized value $y in pattern match (m//) at ./669664.pl line 10.
cond true

In reply to Re: Use of uninitialized value in ... by almut
in thread Use of uninitialized value in ... by pascaldee

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