Are you attempting to compile PHP on Linux and running into, “configure: error: xml2-config not found. Please check your libxml2 installation.”
It’s easy to fix, simply install the libxml2-development package by issuing the following command on your appropriate Linux distribution.
Fixing on Red Hat / CentOS / Fedora via Yum
yum install libxml2-devel
Fixing on Debian / Ubuntu / Linux Mint via apt-get
apt-get install libxml2-dev