c:\@Work\Perl>perl -wMstrict -le
"print qq{perl version: $] \n};
 ;;
 my $x;
 print $x;
 printf '%s', $x;
"

perl version: 5.008009
Use of uninitialized value in print at -e line 1.
Use of uninitialized value in printf at -e line 1.

perl version: 5.010001
Use of uninitialized value $x in print at -e line 1.
Use of uninitialized value $x in printf at -e line 1.