Of course, you don't give us the exact error message or short, self-contained code that will produce it. Is it something like this?

>perl -wMstrict -le
"my @ra = qw(a b c d);
 my $uninitialized;
 print $ra[3];
 print '----------';
 print $ra[$uninitialized];
 print $ra[undef];
"
d
----------
Use of uninitialized value $uninitialized in array element at -e line 
+1.
a
Use of uninitialized value in array element at -e line 1.
a
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