pkgconfig vs find_package

[Mark Jan van Kampen]

I'm a bit unfamiliar with pkgconfig, what is the advantage of looking for libxml2 with pkgconfig instead of find_package?

[Brian Adamson]

The folks who contributed the CMake code are better equipped to answer that than me. I need to dig through the history here to perhaps redirect the question to them. With a quick cursory search, it seems using find_package() might be a preferred approach. For example this mentions some reasons why:
https://stackoverflow.com/questions/29191855/what-is-the-proper-way-to-use-pkg-config-from-cmake