This is a suggestion of compilation directive to use when compiling PHP specifically for the audited code.
The selection made below is based on the extension usage, found in the code (--enable, --with) and also the absence of usage (--disable, --without).
Some local extensions (--pdo-mysql, --with-libmbfl...) are also mentionned for help.
# install one extra extension
#pecl install imagick (https://pecl.php.net/package/imagick)
;;;;;;;;;;;;;;;;;;;;;;;;
; PHP configure list ;
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./configure
--disable-ctype
--disable-fileinfo
--with-gd
--with-jpeg-dir=DIR
--with-png-dir=DIR
--with-xpm-dir=DIR
--with-vpx-dir=DIR
--with-freetype-dir=DIR
--enable-gd-native-ttf
--disable-hash
--without-iconv
--with-imagick=DIR
--enable-intl
--disable-json
--disable-libxml
--enable-mbstring
--with-libmbfl=DIR
--enable-mbstr-enc-trans
--disable-mbregex
--enable-pdo
--with-pdo-odbc
--with-pdo-mysql
--with-pdo-pgsql
--with-pdo-oci
--with-pdo-firebird
--with-pdo-dblib
--with-pdo-cubrid
--without-pear
--disable-posix
--without-sqlite3
--disable-tokenizer
--disable-xml
--disable-xmlreader
--with-xmlrpc[=DIR]
--disable-xmlwriter
; For debug purposes
;--enable-dtrace
;--disable-phpdbg
;--enable-zend-signals
;--disable-opcache