>perl -wE"$r = \my ($x,$y,$z); $$r = '!'; say $x; say $y; say $z"
Use of uninitialized value $x in say at -e line 1.

Use of uninitialized value $y in say at -e line 1.

!

>perl -wE"my $c = my ($x, $y, $z) = (undef, undef); say $c"
2