Bug#395558: more info

[Michael Stroucken <stroucki@ece.cmu.edu>]

Here's the backtrace of trying to do the same tulip action within an
xnest environment.

Program received signal SIGSEGV, Segmentation fault.
0x08157738 in _mesa_shareContext ()
(gdb) bt
#0  0x08157738 in _mesa_shareContext ()
#1  0x0810995a in GlxInitVisuals ()
#2  0x081089c4 in GlxInitVisuals ()
#3  0x080d495c in GlxInitVisuals ()
#4  0x080d4b09 in GlxInitVisuals ()
#5  0x080d091a in XETrapDispatch ()
#6  0x08072aeb in dixDestroyPixmap ()
#7  0x080847d9 in NotImplemented ()
#8  0xa7c4eea8 in __libc_start_main () from /lib/tls/i686/cmov/libc.so.6
#9  0x0805c781 in ?? ()