$ perl -M5.022 -e'
   my $x = 123; \my $y = \$x; say $y;
'
Experimental aliasing via reference not enabled at -e line 2.

$ perl -M5.022 -e'
   use feature qw( refaliasing );
   my $x = 123; \my $y = \$x; say $y;
'
Aliasing via reference is experimental at -e line 3.
123

$ perl -M5.022 -e'
   use feature qw( refaliasing );
   no warnings qw( experimental::refaliasing );
   my $x = 123; \my $y = \$x; say $y;
'
123

$ perl -M5.022 -e'
   use experimental qw( refaliasing );
   my $x = 123; \my $y = \$x; say $y;
'
123