What’s your favourite way to make perl dump core or panic?

The Perl interpreter is quite good at doing the right thing when you give it sensible code, but it's easy to make it crash if you actually try to confuse it. That's a bit of a shame, but for the things that Perl tends to be used for it doesn't really matter that much.

Here are three of my favourites to get you started:

  perl -e 'undef %:: or die'
  perl -e '()= sort {*a=*b, 1} 2,3'
  perl -e '@a=(1..5); map {@a=() if $x++>2, $_} @a'
[download]

All these are still broken in bleadperl, though the last now panics instead of dumping core.

This isn’t wholly frivolous, because it would be useful to have a list of these bugs; though I don't want that to detract from the simple fun of trying to make something break.

Edit: g0n Moved to Meditations from SoPW