my @a=(3,4);

sub x {
  @a = ();
  print "[$_]" for @_;
  print "\n";
}

x(@a);

##</code><code>##

$ perl5220 -w ~/tmp/p
Use of uninitialized value $_ in concatenation (.) or string at /home/davem/tmp/p line 9.
Use of uninitialized value $_ in concatenation (.) or string at /home/davem/tmp/p line 9.
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