[SOLVED] /usr/bin/ld: ../freeglut/libfreeglut_static.a(freeglut_state.o): undefined reference to symbol 'XGetWindowAttributes' in make of Box2d

Issue

I followed this and it showed me steps for installing.
I have dependencies previously installed.
unzip Box2D_v2.1.2.zip cd Box2D_v2.1.2/Box2D/Build cmake .. make

At the last step of make I got the following message.
/usr/bin/ld: ../freeglut/libfreeglut_static.a(freeglut_state.o): undefined reference to symbol 'XGetWindowAttributes' //usr/lib/x86_64-linux-gnu/libX11.so.6: error adding symbols: DSO missing from command line collect2: error: ld returned 1 exit status
I searched online everyone said to compile with -X11flag but this a make file and i dont much abou that

Solution

This error occurs because the CMakeLists.txt file in Testbed is not configured for Linux.

To fix this, open the file Box2D_v2.1.2/Box2D/Testbed/CMakeLists.txt and change the following lines accordingly.

From this:

if(APPLE)
         # We are not using the Apple's framework version, but X11's
         include_directories( /usr/X11/include )
         link_directories( /usr/X11/lib )
         set (OPENGL_LIBRARIES GL GLU GLUT X11)
endif(APPLE)

To this:

if(UNIX)
        # We are not using the Apple's framework version, but X11's
        include_directories( /usr/X11/include )
        link_directories( /usr/X11/lib )
        set (OPENGL_LIBRARIES GL GLU X11)
endif(UNIX)

This worked for me.

Answered By - John Escobia