Installing PEAR environment:      /usr/local/lib/php/
/usr/src/www/php/php-5.5.33/sapi/cli/php: symbol lookup error:     /usr/src/www/php/php-5.5.33/sapi/cli/php: undefined symbol: __xmlFree
Makefile:390: recipe for target 'install-pear-installer' failed
make[1]: *** [install-pear-installer] Error 127
Makefile:393: recipe for target 'install-pear' failed
make: *** [install-pear] Error 2

libxslt.so.1 => /usr/lib/x86_64-linux-gnu/libxslt.so.1 (0x00007efd9c207000)
libxml2.so.2 => /usr/lib/x86_64-linux-gnu/libxml2.so.2 (0x00007efd9bea0000)

checking for xml2-config path... /usr/local/bin/xml2-config
checking whether libxml build works... yes

$ readelf -s /usr/local/lib/libxml2.so.2 | grep -i __xmlfree
1409: 00000000000e0b5c    35 FUNC    GLOBAL DEFAULT   12 __xmlFree
5249: 00000000000e0b5c    35 FUNC    GLOBAL DEFAULT   12 __xmlFree

$ cat /etc/ld.so.conf
include /etc/ld.so.conf.d/*.conf

$ cat /etc/ld.so.conf.d/libs.conf
/usr/local/lib
/usr/lib/x86_64-linux-gnu/libfakeroot

./configure --prefix=/usr/local
CFLAGS="-O2 -mtune=native -funroll-loops -fPIC"
--with-libdir=lib
--with-apxs2=/usr/local/apache2/bin/apxs
--disable-debug
--disable-short-tags
--enable-libgcc
--enable-shared=yes
--enable-calendar
--enable-exif
--enable-ftp
--enable-gd-native-ttf
--enable-mbstring
--enable-shmop
--enable-soap
--enable-sockets
--enable-sysvmsg
--enable-sysvsem
--enable-sysvshm
--with-bz2
--with-curl=/usr/local
--with-freetype-dir
--with-gd
--with-gnu-ld
--with-iconv-dir=/usr/local
--with-jpeg-dir=/usr/local
--with-ldap=/usr/local
--with-libxml-dir=/usr/local
--with-mcrypt
--with-mhash
--with-openssl
--with-openssl-dir=/usr/local
--with-pear
--with-pcre-regex=/usr/local
--with-pcre-dir=/usr/local
--with-png-dir=/usr/local
--with-tidy
--with-readline
--with-tsrm-pthreads
--with-xmlrpc
--with-xsl=/usr/local
--with-zlib
--with-mysqli=mysqlnd
--with-pdo-mysql=mysqlnd
--without-sqlite3
--without-pdo-sqlite

export EXTRA_LDFLAGS_PROGRAM=-L/usr/local/curl-7.49.1/lib

export EXTRA_LDFLAGS_PROGRAM=-L/usr/local/lib/

--libdir=DIR            object code libraries in DIR [EPREFIX/lib]