mcgreg@pegasos:~$ gdb /usr/bin/glxinfo 
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Reading symbols from /usr/bin/glxinfo...(no debugging symbols found)...done.
(gdb) run
Starting program: /usr/bin/glxinfo 
[Thread debugging using libthread_db enabled]
name of display: :0.0

Program received signal SIGSEGV, Segmentation fault.
0x00007ffff7398d44 in pthread_mutex_lock () from /lib/libpthread.so.0
(gdb) bt
#0  0x00007ffff7398d44 in pthread_mutex_lock () from /lib/libpthread.so.0
#1  0x00007ffff57b11cf in _mesa_reference_buffer_object (ctx=0x62e2a0, ptr=0x63dff8, bufObj=0x620160) at main/bufferobj.c:249
#2  0x00007ffff58234f3 in _mesa_init_pixelstore (ctx=0x62e2a0) at main/pixelstore.c:259
#3  0x00007ffff57ba490 in init_attrib_groups (ctx=0x62e2a0, api=<value optimized out>, visual=<value optimized out>, share_list=<value optimized out>, 
    driverFunctions=<value optimized out>, driverContext=0x62a390) at main/context.c:702
#4  _mesa_initialize_context_for_api (ctx=0x62e2a0, api=<value optimized out>, visual=<value optimized out>, share_list=<value optimized out>, 
    driverFunctions=<value optimized out>, driverContext=0x62a390) at main/context.c:870
#5  0x00007ffff57ba7df in _mesa_create_context_for_api (api=API_OPENGL, visual=0x61f5b0, share_list=0x0, driverFunctions=0x7fffffffd690, driverContext=0x62a390)
    at main/context.c:1006
#6  0x00007ffff57855ef in radeonInitContext (radeon=0x62a390, functions=<value optimized out>, glVisual=0x61f5b0, driContextPriv=0x6200b0, 
    sharedContextPrivate=0x620160) at radeon_common_context.c:197
#7  0x00007ffff576350b in r600CreateContext (api=<value optimized out>, glVisual=0x61f5b0, driContextPriv=0x6200b0, sharedContextPrivate=0x0) at r600_context.c:395
#8  0x00007ffff575ad2a in dri2CreateNewContextForAPI (screen=0x61df10, api=0, config=0x61f5b0, shared=<value optimized out>, data=0x620160)
    at ../common/dri_util.c:662
#9  0x00007ffff7bb7c09 in dri2CreateContext (psc=0x6125b0, mode=0x622ab0, gc=0x614f60, shareList=<value optimized out>, renderType=<value optimized out>)
    at dri2_glx.c:150
#10 0x00007ffff7b8fa45 in CreateContext (dpy=0x606010, generic_id=203, fbconfig=<value optimized out>, shareList=0x0, allowDirect=<value optimized out>, code=3, 
    renderType=32788, screen=0) at glxcmds.c:403
#11 0x00007ffff7b91038 in glXCreateContext (dpy=0x606010, vis=0x614cd0, shareList=0x0, allowDirect=1) at glxcmds.c:527
#12 0x00000000004022d7 in ?? ()
#13 0x0000000000402e21 in ?? ()
#14 0x00007ffff705aabd in __libc_start_main () from /lib/libc.so.6
#15 0x0000000000401379 in ?? ()
#16 0x00007fffffffe238 in ?? ()
#17 0x000000000000001c in ?? ()
#18 0x0000000000000001 in ?? ()
#19 0x00007fffffffe522 in ?? ()
#20 0x0000000000000000 in ?? ()