$ perl -wE'
my %FORM = ( a => "abc", b => "defg" );
say do { no warnings; length join "", %FORM };
say $];'
9
5.010001

$ perl -wE'
my %FORM = ( a => "abc", b => "defg" );
say do { no warnings; length join "", %FORM };
say $];'
9
5.016000