use strict;
use warnings;

my $text = "a b c";
print "Without utf8::upgrade...\n";
while ( $text =~ /(\S)/g ) { 
    print "$1\n";
}
print "With utf8::upgrade...\n";
while ( $text =~ /(\S)/g ) { 
    print "$1\n";
    utf8::upgrade($1);
}

print "Problem persists...\n";
my $more_text = "d e f";
while ( $more_text =~ /(\S)/g ) { 
    print "$1\n";
}