&reftitle.install;

The PCRE extension is a core PHP extension, so it is always enabled. By default, this extension is compiled using the bundled PCRE library. Alternatively, an external PCRE library can be used by passing in the `--with-pcre-regex=DIR` configuration option where `DIR` is the location of PCRE's include and library files. It is recommended to use PCRE 8.10 or newer; as of PHP 7.3.0, PCRE2 is required.

PCRE's just-in-time compilation is supported by default, which can be disabled with the `--without-pcre-jit` configuration option as of PHP 7.0.12.

&windows.builtin;

PCRE is an active project and as it changes so does the PHP functionality that relies upon it. It is possible that certain parts of the PHP documentation is outdated, in that it may not cover the newest features that PCRE provides. For a list of changes, see the PCRE library changelog and also the following bundled PCRE history:

# Upgrade history of the bundled PCRE library

PHP &Version; | Updated PCRE &Version; | Notes
8.2.0 | 10.40 |
8.1.0 | 10.39 |
7.4.12, 8.0.0 | 10.35 |
7.4.6 | 10.34 |
7.4.0 | 10.33 |
7.3.0 | 10.32 |
7.2.0 | 8.41 |
7.0.3 | 8.38 | See CVE-2015-8383, CVE-2015-8386, CVE-2015-8387, CVE-2015-8389, CVE-2015-8390, CVE-2015-8391, CVE-2015-8393, CVE-2015-8394
7.0.0 | 8.37 | See CVE-2015-2325, CVE-2015-2326