There is a regression in PCRE 8.21 when matching with JIT in UTF-8 mode. This should not match: echo ETA | pcregrep -u '(?i)(?<!b|th|z|m|p|^)eta(?!\w)' Reported to upstream <http://bugs.exim.org/show_bug.cgi?id=1231> and fixed in SVN commit r953 | zherczeg | 2012-03-29 19:41:57 +0200 (Čt, 29 bře 2012) | 1 line Fixed a bug for backward assertions with REVERSE 0 in the JIT compiler F17 and F18 are affected. F16 and older releases are not.
Fixed as pcre-8.30-3.fc18 in F18.
pcre-8.21-3.fc17 has been submitted as an update for Fedora 17. https://admin.fedoraproject.org/updates/pcre-8.21-3.fc17
Package pcre-8.21-3.fc17: * should fix your issue, * was pushed to the Fedora 17 testing repository, * should be available at your local mirror within two days. Update it with: # su -c 'yum update --enablerepo=updates-testing pcre-8.21-3.fc17' as soon as you are able to. Please go to the following url: https://admin.fedoraproject.org/updates/FEDORA-2012-5329/pcre-8.21-3.fc17 then log in and leave karma (feedback).
pcre-8.21-3.fc17 has been pushed to the Fedora 17 stable repository. If problems still persist, please make note of it in this bug report.