After thinking som more about it, you most likely are on the hunt for the increase in memory consumption resp. cause of the lvalue substr memory consumption.

If you have the time and machine, there is bisect-runner.pl in recent versions of Perl (starting somewhere in the 5.15.x series) that will chug through the commits starting from a known good (or known bad) version, and find the commit where the behaviour switches.

In reply to Re: Perl5 patches by Corion
in thread Perl5 patches by BrowserUk

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