While I like that Perl doesn't allow this to block the engine, I'm not too sure about the solution.

Ignoring regex grammar to silently continue might be worse than throwing an explicit warning.

Regex-Problem: Empty match detected, trying continuation...

Alike the "deep recursion" warning if Perl dives 100 times deep into the same sub.

But I don't think I know the RE algebra good enough to tell.

update

s/1000/100/