There is no need to report this, please check this web page: cannot use regexp inside (?{})

I pasted a piece of it here, and hightlighted one sentence, which gives the why:

"Regex Engine Reentrancy
Stéphane Payrard reported that Perl dumps core if you try to do a regex match inside of a (?{...}) expression. This did not come as a big surprise seeing as the regex engine is not reentrant. (It uses several global variables.)
Hugo van der Sanden: Making the regexp engine reentrant should fix the problem.
Jarkko Hietaniemi: This is a bit like saying, "Stopping the wars should bring the world peace."
Stéphane suggested making it a fatal error in the meantime, but no patch was offered.
Somewhere in the discussion, Jesus Quiroga mentioned that he was working on a replacement for perlre.pod, including a tutorial and some examples. It's about time!"

In reply to Re: Using regexes inside of (?{}) by pg
in thread Using regexes inside of (?{}) by diotalevi

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