There have been some pretty large changes in the internals of perl's IO handling when going from 5.6 to 5.8. But seen from the language, there are no backwards compatability issues. So, even if your wished script would exist, it still wouldn't report something.

It's not inconcievable a memory leak was introduced in 5.8. Please create a small program that doesn't leak on 5.6, but does leak on 5.8, and report it using perlbug as soon as you can. Jarkko released release candidate 2 for 5.8.1 today, but will be away for the next two weeks, meaning that there is sometime left for someone to write a patch to be included in 5.8.1. Unless the bug is already known and fixed of course. But don't hesitate, spend some time isolating the bug from your code now, otherwise you might have to wait another year or so before there's a perl that doesn't leak memory.

Abigail