Installation
mbstring is a non-default extension. This means it
is not enabled by default. You must explicitly enable the module with
the configure option. See the
Install section for details.
The following configure options are related to the
mbstring module.
-
--enable-mbstring: Enable
mbstringfunctions. This option is required to usembstringfunctions.libmbfl is necessary for
mbstring. libmbfl is bundled withmbstring. Prior to PHP 7.3.0, if libmbfl is already installed on the system, --with-libmbfl[=DIR] can be specified to use the installed library. -
--disable-mbregex: Disable regular expression functions with multibyte character support.
Oniguruma is necessary for the regular expression functions with multibyte character support. As of PHP 7.4.0, pkg-config is used to detect the libonig library. Prior to PHP 7.4.0, Oniguruma was bundled with
mbstring, but it was possible to build against an already installed libonig by passing --with-onig[=DIR].It is possible to disable the multibyte regex backtrack check by specifying --disable-mbregex-backtrack.

