Bus error when running xgraph examples!

[Cheng Liang <p144850032@netease.com>]

Dear all,
     I met bus error when I tried run "xgraph examples/surface.xg". The
same errors with the surface2.xg and surface3.xg. But the other examples
are OK, such as xgtest.xg,bar.xg and Animation.xg.
The following was the message I got. What's the problem? ANyone met the 
same problem in HPUX 10.02? Thank you all in advance!


     $xgraph surface.xg
Bus error(coredump)

(gdb) file xgraph
Reading symbols from xgraph...(no debugging symbols found)...done.
(gdb) run surface.xg
Starting program: /nfs/dkr2/users/e5lcheng/ns-allinone-2.1b5/bin/xgraph surface.xg
warning: Unable to find __d_pid symbol in object file.
warning: Suggest linking with /opt/langtools/lib/end.o.
warning: GDB will be unable to track shl_load/shl_unload calls
(no debugging symbols found)...(no debugging symbols found)...
(no debugging symbols found)...(no debugging symbols found)...
Program received signal SIGBUS, Bus error.
0x18eac in Der1 ()
(gdb) backtrace
#0  0x18eac in Der1 ()
#1  0x18440 in ReadData ()
#2  0x4ac0 in main ()

**********************
Cheng Liang
Radar  Lab, S1-B4a-03
School of E.E.E.
Nanyang Technological University,
Singapore 639798