Re: Debugging 32bit apps with 64bit target gdb

[Paul Smith <psmith@gnu.org>]

On Mon, 2011-05-23 at 00:40 +0200, Mark Kettenis wrote:
> > From: Paul Smith <psmith@gnu.org>
> > Date: Sun, 22 May 2011 18:25:10 -0400
> > 
> > A short summary, I'm trying to see if I can build one GDB executable
> > with all these properties:
> > 
> >       * Is a 32bit application so it can run on both 32bit and 64bit
> >         systems
> >       * Can debug 32bit applications
> >       * Can debug 64bit applications (when run on a 64bit system
> >         obviously)
> >       * If I can get it to debug a 64bit core file when running on a
> >         32bit system (with --sysroot pointing to a 64bit sysroot of
> >         course) that would be awesome.
> > 
> > I'm only concerned with x86 architectures (for now?)
> > 
> > Is such a thing possible?
> 
> I believe this is possible on Solaris.  It is possible on powerpc
> Linux.  It is *not* possible on Linux.  Not GDB's fault.  The x86
> Linux kernel simply doesn't provide the necessary support.

Yes, I'm using Linux.  Sorry to forget that detail.

Interesting.  I could have sworn I've seen this work before but maybe
there was simply magic going on behind the scenes (gdb was a shell
script that invoked a correct version based on the target architecture,
or something).

So, I need to build a 32bit GDB to debug 32bit apps and a 64bit GDB to
debug 64bit apps?

Thanks!

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