Get Different Result for the same core file with different versions of gdb.

[Simon Marchi]

> Hi Simon:
>   Thanks for your reply!  Actually I am debugging postgresql bug, however
> I can't reproduce the core at last,  so the simple answer for your question is
> no, I can't provide the reproducer. I'm sorry about that.  But if you want any
> further analysis on the current core file,  I can try my best. 

I don't know core file handling well enough to provide you with
precise instructions to guide you.  If I had that it front of me, I
would probably check which address GDB is trying to read (if it's the
same in both cases).  I would inspect the LOAD program headers of the
core file, see what's the content at that address.  If I find that GDB
indeed is not reading the right content, I would try to bridge the gap
between where LOAD program headers from the core file are processed and
where memory is read in GDB, to try to find where the chain is broken.

The relevant code for that is probably in gdb/corelow.c.

Simon