It would seem this area of perl is exceedingly difficult to fix, based on this bug (raised by the World's Greatest Perl golfer, I notice;-) in December 2002 and this one reported in March 2003 and this similar one (raised by someone who Ton used to beat over the head with his one iron at golf;-) reported in July 2003.

In reply to Re: (?{...code..}) regex construct causing panic: top_env in 5.8.2 by eyepopslikeamosquito
in thread (?{...code..}) regex construct causing panic: top_env in 5.8.2 by leriksen

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