[MPlayer-dev-eng] Should #include <X11/extensions/XShm.h> be conditional?

[Ingo Brückl]

While currently checking the #ifdefs in the GUI code and whether they are
necessary, I came across #include <X11/extensions/XShm.h>. As an extension,
it doesn't necessarily have to be present, does it?

As far as I can see, there is no check or CONFIG definition for XShm in the
configure script.

Should there be a condition for this include (and the function calls)?

(Yeah, I know, this isn't exactly the direction I'm heading for...)

Ingo