You could probably use use B qw/svref_2object/; my $flags = svref_2object(\$val)->FLAGS;, but Tux's Data::Peek seems to have pretty nice interface:

use warnings;
use strict;
use Data::Dump;
use Data::Peek qw/DDump/;

my $x = "2.7";
dd {DDump $x}->{FLAGS};
dd $x; # changes flags
dd {DDump $x}->{FLAGS};

__END__

{ IsCOW => 1, POK => 1, pPOK => 1 }
2.7
{ IsCOW => 1, NOK => 1, pIOK => 1, pNOK => 1, POK => 1, pPOK => 1 }
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