I can't see how this could be related to my examples since in 
perl -we'use strict; sub foo {}; my $a; foo( %{ $a } )'

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the expression %{ $a } isn't in lvalue context. Also autovivification doesn't appear only in lvalue context: 
perl -MData::Dumper -we'use strict; my $a; $a->{b}{c}; print Dumper $a
+'
$VAR1 = {
          'b' => {}
        };

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In reply to Re^2: Strange behaviour of interpreter when dereferencing an undefined value by kejv2
in thread Strange behaviour of interpreter when dereferencing an undefined value by kejv2

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