Re: PCRE JIT stack size limit

On 24.07.2015, at 09:33, Adam Harvey <aharvey@php.net> wrote: > > On 23 July 2015 at 11:47, Christoph Becker <cmbecker69@gmx.de> wrote: > <snip great explanation, thanks> >> Therefore I tend to prefer a new ini setting (say, pcre.jitstack_limit). >> That would mean, however, to add yet another ini setting, of which >> there are already so many. > > I'm not a big fan of that, although it's at least in the spirit of > what configuration settings are meant to be used for. > > What if we added the PCRE_ERROR_JIT_STACKLIMIT error constant to those > exposed to userland so that it's more easily noticed via > preg_last_error(), and adding a modifier that can be used to disable > the JIT on a per-pattern basis (by setting PCRE_NO_START_OPTIMIZE, > which admittedly disables other stuff too, but at least the regex will > run)? At least then users could check the error when the regex fails > and re-run the regex without the JIT if they chose to. But this might mean that patterns which previously worked, because no JIT was used, suddenly fail in existing code with a new error constant. Which I guess is a BC break.