my ($a, $b);

$a = \$b; #my $a='b';
$b = '1'; #my $b='1';

$a = '2'; #$$a='2'; # Wrong, $$a would dereference $a, but you failed to create a proper ref in first place.
						  # that's why 'use strict' complained.  Nothing should have printed unless you 
						  # defeated 'use strict' in which case perl guesses that you are trying to 
						  # make a reference and correctly prints '1'.

print $b;

# I assume you are experimenting with references?