Make some dynamic X11 symbols option. _XData32 and _XRead32 are only available on 64-bit systems, and are chosen with macros in the X11 headers. So on 32-bit systems, it should fail to find these symbols and keep going anyhow.

Makefile.in
Makefile
.libs
*.o
*.lo
*.la
SDL_systhread.c
SDL_systhread_c.h
SDL_syssem.c
SDL_syssem_c.h
SDL_sysmutex.c
SDL_sysmutex_c.h
SDL_syscond.c
SDL_syscond_c.h
clone.S