DB<32> $x=0;for(1..2**31) {print;last if $x++>5}
Range iterator outside integer range at (eval 36)[/usr/share/perl/5.10/perl5db.pl:638] line 2.
 
  DB<33> $x=0;for(1..2**30) {print;last if $x++>5}
1234567

  DB<34> $x=0;for(1..~0) {print;last if $x++>5}
Range iterator outside integer range at (eval 45)[/usr/share/perl/5.10/perl5db.pl:638] line 2.