[xml] How to detect at run-time whether libxml2 was compiled with enabled mutlithreading support?

["Andrew W. Nosenko" <andrew w nosenko gmail com>]

How to detect at run-time whether libxml2 was compiled with the 
mutlithreading support enabled (--with-threads)?

Reason of question: I just try to avoid following scenario:
  1. application builded and tested on the machine with thread-aware
      libxml2 (--with-threads).  Application linked dynamically with
libxml2, of course.
  2. user copied application (binary) to the machine where libxml2
builded without
      threads support (--without-threads).
  3. Application misteriously fails :-(

Thanks in advance.

--
Andrew W. Nosenko <andrew w nosenko gmail com>