christopher@christopher-desktop:~/Desktop/crystalspace-src-1.2$ make

    g++ -c -o ./out/linuxx86/optimize/plugins/video/canvas/xextshm/xextshm.o -I. -I./include -I./include -pipe -Wall -Wno-unknown-pragmas -fvisibility=hidden -march=i586 -mtune=generic -I/usr/local/include -fno-exceptions -fvisibility-inlines-hidden -O3 -fomit-frame-pointer -ffast-math -g2 -fPIC  plugins/video/canvas/xextshm/xextshm.cpp

In file included from plugins/video/canvas/xextshm/xextshm.cpp:26:
plugins/video/canvas/xextshm/xextshm.h:38:35: error: X11/extensions/XShm.h: No such file or directory
plugins/video/canvas/xextshm/xextshm.h:54: error: ‘XShmSegmentInfo’ does not name a type
plugins/video/canvas/xextshm/xextshm.cpp: In constructor ‘csXExtSHM::csXExtSHM(iBase*)’:
plugins/video/canvas/xextshm/xextshm.cpp:40: error: ‘shmi’ was not declared in this scope
plugins/video/canvas/xextshm/xextshm.cpp: In member function ‘virtual unsigned char* csXExtSHM::CreateMemory(int, int)’:
plugins/video/canvas/xextshm/xextshm.cpp:83: error: ‘shmi’ was not declared in this scope
plugins/video/canvas/xextshm/xextshm.cpp:83: error: ‘XShmCreateImage’ was not declared in this scope
plugins/video/canvas/xextshm/xextshm.cpp:106: error: ‘XShmAttach’ was not declared in this scope
plugins/video/canvas/xextshm/xextshm.cpp: In member function ‘virtual void csXExtSHM::DestroyMemory()’:
plugins/video/canvas/xextshm/xextshm.cpp:123: error: ‘shmi’ was not declared in this scope
plugins/video/canvas/xextshm/xextshm.cpp:124: error: ‘XShmDetach’ was not declared in this scope
plugins/video/canvas/xextshm/xextshm.cpp:129: error: ‘shmi’ was not declared in this scope
plugins/video/canvas/xextshm/xextshm.cpp:133: error: ‘shmi’ was not declared in this scope
plugins/video/canvas/xextshm/xextshm.cpp:136: error: ‘shmi’ was not declared in this scope
plugins/video/canvas/xextshm/xextshm.cpp: In member function ‘virtual void csXExtSHM::Print(Window, _XGC*, const csRect*)’:
plugins/video/canvas/xextshm/xextshm.cpp:147: error: ‘XShmPutImage’ was not declared in this scope
plugins/video/canvas/xextshm/xextshm.cpp:153: error: ‘XShmPutImage’ was not declared in this scope
...skipped xextshm.so for lack of <plugins!video!canvas!xextshm!>xextshm.o...
make: *** [all] Error 1
christopher@christopher-desktop:~/Desktop/crystalspace-src-1.2$