Re: Can't debug core files with GDB

[Daniel Jacobowitz <dan@debian.org>]

On Tue, May 16, 2006 at 05:02:35PM -0700, Tony Lin wrote:
> When I force a core file and try to debug it, I get empty values:
> 
> >./gdb ./nebtest ./core.524.nebtest
> 
> GNU gdb 6.4
> Copyright 2005 Free Software Foundation, Inc.
> GDB is free software, covered by the GNU General Public License, and you are
> welcome to change it and/or distribute copies of it under certain 
> conditions.
> Type "show copying" to see the conditions.
> There is absolutely no warranty for GDB.  Type "show warranty" for details.
> This GDB was configured as "mips-linux"...Using host libthread_db
> library "/lib/libthread_db.so.1".
> 
> Core was generated by `./nebtest'.
> Program terminated with signal 11, Segmentation fault.
> Reading symbols from /lib/libgcc_s.so.1...done.
> Loaded symbols for /lib/libgcc_s.so.1
> Reading symbols from /lib/libc.so.6...done.
> Loaded symbols for /lib/libc.so.6
> Reading symbols from /lib/ld.so.1...done.
> Loaded symbols for /lib/ld.so.1
> #0  0x00000000 in ?? ()
> (gdb) bt
> #0  0x00000000 in ?? ()
> #1  0x00000000 in ?? ()

Check the contents of the core file with objdump?  I recall seeing at
least one recent MIPS kernel which failed to save registers.  Take a
look at the .reg section.

-- 
Daniel Jacobowitz
CodeSourcery