$ perl -MData::Dump -e 'my $x; $x->[0]->{"aaa"}; dd $x'
[{}]
$ perl -MData::Dump -M-autovivification -e \
      'my $x; $x->[0]->{"aaa"}; dd $x'
undef

##</code><code>##

$ perl -MData::Dump -M-autovivification=strict,fetch -e \
      'my $x; $x->[0]->{"aaa"}; dd $x'
Reference vivification forbidden at -e line 1.