[RFC][UNDER DISCUSSION] Oniguruma maintenance end and future of mbregex(End of mbregex)

> > As far as I understand, mbstring extension internally uses library > named oniguruma, which provides regex support for mb_ereg* and few > other functions. Oniguruma reached EOL almost year ago. This RFC > proposes deprecation and subsequent removal of all regex related > functions from mbstring extension and removing dependency on > oniguruma. Instead, Yuya offers pie extension named mb_onig/mb_onig, > which is a new home for those functions. For that goal he forked > oniguruma for providing updates on security and unicode version.

> > 2026年3月24日(火) 20:46 Juliette Reinders Folmer > <php-internals_nospam@adviesenzo.nl>: > > > > On 23-3-2026 1:34, youkidearitai wrote: > > > > Hi, Internals > > > > I decide deprecate mbregex in 8.6 and drop in 9.0. > > So I would like to go to Under Discussion phase. > > https://wiki.php.net/rfc/eol-oniguruma > > https://github.com/php/php-src/pull/21490 > > > > > > Thank you for writing this RFC. I don't have a strong opinion either way. I fully understand that maintaining the Oniguruma library, while it was abandoned by the original project is a huge and unenviable task. > > > > Having said that, I am very curious what Ruby will be using going forward and if PHP could adopt a similar solution. > > I also wonder if there are no other "blessed" forks of the Oniguruma library to which PHP could switch. > > I believe this should be investigated and the results of this investigation should be added to the RFC to (potentially) strengthen the case for the current proposal, or, depending on the findings, it could be that the current proposal could be adjusted based on what this investigation throws up. > > > > Secondly, I believe the RFC would benefit from a more detailed section about what PHP devs can do to mitigate the deprecation. > > For example, if the only expected text encoding is UTF-8, people can use `preg_*()` functions with the `u` modifier instead of the `mb_ereg*()` functions. > > > > I also think it is important to mention that the Symfony Mbstring[1] polyfill package does **NOT** polyfill the MB regex functionality, so cannot be used as a replacement/alternative. > > > > With this in mind, I also believe the impact analysis in the RFC should be expanded as the MbString extension is widely used. > > > > To support this, I've created a branch in the PHPCompatibility package [2] specifically for this deprecation and I have run the relevant checks over the Packagist Top 4000 (as of yesterday). > > > > I've posted the used ruleset and the full results as a gist. > > https://gist.github.com/jrfnl/bd0f66f1c185930427db4f093babf214 > > > > Summary of findings: > > > > PHP CODE SNIFFER VIOLATION SOURCE SUMMARY > > ------------------------------------------------------------------------------------------- > > SOURCE COUNT > > ------------------------------------------------------------------------------------------- > > PHPCompatibility.FunctionUse.RemovedFunctions.mb_splitDeprecated 30 > > PHPCompatibility.FunctionUse.RemovedFunctions.mb_regex_encodingDeprecated 25 > > PHPCompatibility.FunctionUse.RemovedFunctions.mb_eregi_replaceDeprecated 20 > > PHPCompatibility.FunctionUse.RemovedFunctions.mb_ereg_replaceDeprecated 18 > > PHPCompatibility.FunctionUse.RemovedFunctions.mb_ereg_matchDeprecated 13 > > PHPCompatibility.FunctionUse.RemovedFunctions.mb_ereg_search_initDeprecated 10 > > PHPCompatibility.FunctionUse.RemovedFunctions.mb_ereg_search_regsDeprecated 9 > > PHPCompatibility.FunctionUse.RemovedFunctions.mb_ereg_replace_callbackDeprecated 6 > > PHPCompatibility.FunctionUse.RemovedFunctions.mb_ereg_search_getregsDeprecated 5 > > PHPCompatibility.FunctionUse.RemovedFunctions.mb_eregDeprecated 4 > > PHPCompatibility.FunctionUse.RemovedFunctions.mb_ereg_search_setposDeprecated 4 > > PHPCompatibility.FunctionUse.RemovedFunctions.mb_eregiDeprecated 2 > > PHPCompatibility.FunctionUse.RemovedFunctions.mb_ereg_search_posDeprecated 1 > > ------------------------------------------------------------------------------------------- > > A TOTAL OF 147 SNIFF VIOLATIONS WERE FOUND IN 13 SOURCES > > ------------------------------------------------------------------------------------------- > > > > So, 147 occurances in the Packagist top 4000 in total. > > > > While this is lower than I would have expected, it should be remembered that most distributed packages will default to/require UTF-8 encoding and that code handling non-UTF8 encodings - and therefore needing the Mb regex functionality - is mostly found in proprietary packages. > > > > The PIE extension would help those packages. > > > > Another potential alternative for those packages would be to convert all their data and code to a UTF-8 base, which will be a humongous project for most (and that deserves a mention in the RFC). > > > > Hope this helps. > > > > Smile, > > Juliette > > > > > > 1: https://symfony.com/packages/polyfill-mbstring > > 2: https://github.com/PHPCompatibility/PHPCompatibility/commit/47ba8b691f82d13dcfe496549c1110d250e18a8c > > 3: https://gist.github.com/jrfnl/bd0f66f1c185930427db4f093babf214 > > Hi, Juliette > > Thank you very much for your gist. > I saw your gist, seems like depends mbregex(Oniguruma). > > > Having said that, I am very curious what Ruby will be using going forward and if PHP could adopt a similar solution. > > I also wonder if there are no other "blessed" forks of the Oniguruma library to which PHP could switch. > > I believe this should be investigated and the results of this investigation should be added to the RFC to (potentially) strengthen the case for the current proposal, or, depending on the findings, it could be that the current proposal could be adjusted based on what this investigation throws up. > > Indeed, There is a Onigmo in > Ruby(https://github.com/ruby/ruby/blob/master/regexec.c) that fork > from Oniguruma. > There are Onigmo and Oniguruma differences. > > I wrote your feedback to RFC. > And I quoted your gist result. Please let me know if there is any problem. > Thank you again. > > Regards > Yuya > > -- > --------------------------- > Yuya Hamada (tekimen) > - https://tekitoh-memdhoi.info > - https://github.com/youkidearitai > -----------------------------