x86_64 gdb and objdump

["Srinivas Murthy" <codevana at gmail dot com>]

> From a core dump file, I see that with gdb I get a "Cannot access
memory at address xx" msg but using objdump, I can see the contents of
the memory location on the core file.

Any ideas what is going wrong?

Thanks.

# gdb test core_dir/core.test.30235
GNU gdb 6.6
Copyright (C) 2006 Free Software Foundation, Inc.
GDB is free software, covered by the GNU General Public License, and you are
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There is absolutely no warranty for GDB.  Type "show warranty" for details.
This GDB was configured as "x86_64-unknown-linux-gnu"...
Using host libthread_db library "/lib64/libthread_db.so.1".
Core was generated by `./test'.
Program terminated with signal 11, Segmentation fault.
#0  0x00000000004004f5 in bar () at test.c:10
10      test.c: No such file or directory.
       in test.c
(gdb) bt
#0  0x00000000004004f5 in bar () at test.c:10
Cannot access memory at address 0x7fbfffee98


However, objdump shows that there is some valid content at the location:

# objdump -D /tmp/core.test.30235 |less |grep 7fbfffee98
 7fbfffe95f:   00 08                   add    %cl,(%rax)