So I'm trying to build Allegro 5.1.11 on Slackware 13.37.0.

Actually, I built it no problem on one such computer, but now a couple others (a 64 bit and a 32 bit) are refusing to build it because they say:

CMake Error at CMakeLists.txt:632 (message):
X11 support requires XInput2 library version 2.2 or higher.

I do have a file:

/usr/include/X11/extensions/XInput2.h

So I do not understand what exactly Allegro needs here, and I don't know whether I'm mussing a file of sufficient version or if I have it but it's just not finding it.

I tried 5.1.10 and .9 and found out that .9 does not complain about missing XInput2.2 during configure.

I have probably 5.1.9 running happily on one slackware 13.37.0 box, but that same box won't let me configure 5.1.11.

I would be most grateful for some guidance on what I can do to make this work, and why it's not working. Obviously whatever XInput2 2.2 is I don't need it because my app happily works with 5.1.9 on one computer.

Unfortunately, I cannot get 5.1.9 to compile on some other computers. It configures but then throws some errors about Touch stuff during make.

Thank you very much,

Jesse