This version of libxml introduced quite a few changes. Most of
them are differences in error reporting, while some also change
behavior, e.g. null bytes are no longer supported and xinclude
recursion is limited.
Closes GH-7030. Closes GH-7046.
Co-authored-by: Nikita Popov <nikic@php.net>
This method was used to protect code against XXE processing attacks.
Since PHP now requires libxml >= 2.9.0 external entity loading no longer
needs to be disabled to prevent these attacks. It is disabled by default.
Also, the method has an unwanted side effect that causes a lot of
confusion: Parsing XML data from resources like files is no longer possible.
Closes GH-5867.
