A quick web search showed that the answer is yes, any usage of the bad variables slows down regex matching for everybody.

A module, Devel::SawAmpersand, was mentioned that tells if the sawampersand flags was set. And Devel::FindAmpersand tells where it was set.

In reply to Re: Naughty Regular Expressions and mod_perl by iburrell
in thread Naughty Regular Expressions and mod_perl by Ovid

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