RFC: support debug info in separate files

[Andrew Cagney]

Hmm, to wear fernando's hat :-)  Is there a new test that demonstrates 
this feature?

> Some random comments...
> 
> This works only for Elf. Will this interfere when other file formats
> are processed? (I haven't tried with a, say, coff file, which is
> impossible of course because this is elfutils based).
> 
>  > 	* utils.c (calc_crc32): New function.
>  > 	* defs.h (calc_crc32): New declaration.
> 
> Now we have 4 identical crc32's functions in gdb. Any chance to
> delete a few?
> 
> For the debug file name suggest looking at HAVE_DOS_BASED_FILE_SYSTEM
> in libiberty, and its uses in gdb/source.c.
> 
> [...]
> 
>  > +  strcat (debugfile, ".debug/");
> [...]
> 
>  > +  strcat (debugfile, "/");
> 
> [...]
>  > +  strcat (debugfile, "/");
> 
> Should these be DIR_SEPARATOR instead? I guess DJGPP doesn't care though.
> 
> In this message,
> http://sources.redhat.com/ml/gdb/2002-09/msg00312.html I pointed out a
> few things that could be done to improve this patch.  For instance,
> instead of adding a completely new objfile that would be only for the
> debug info, add the debug info to the existing objfiles.  I haven't
> had a chance to see if you changed the patch to do something different
> or not.  It also seemed at that stage that we were gaining an extra
> copy of the minimal symbols, and this can bloat gdb even more. Was
> this changed?
> 
> Other comments I pointed out in that message have been addressed by
> Alex already.
> 
> Elena
> 
> 
>