Re: GUD GDB integration

[Eli Zaretskii <eliz@gnu.org>]

> From: Juan Rafael García Blanco <jrblanco@gmv.com>
> Date: Thu, 24 May 2018 06:05:04 +0000
> 
> > > If so, why is this approach better than writing event handlers using gdb's
> > scheme interpreter?
> >
> > Not sure what you mean by that.  How would Emacs invoke the GDB's
> > Guile interface?
> >
> Well, actually, gdb's guile/python interface would invoke Emacs back when
> hitting a breakpoint, exception, ... I think it is a way to handle gdb events
> synchronously, instead of reading and parsing gdb's output; but that would
> require a connection from the guile part back to Emacs.

I don't see how such a "connection" could work.  The available methods
of communications supported by Emacs either assume Emacs is talking to
a subprocess (via a PTY or a pipe), or support simple display-related
operations used by emacsclient.  Anything else will need development
on the Emacs side, and it cannot be done in Lisp, AFAIU.

IOW, there's no way currently to have Guile interpreter in GDB to
"invoke" Emacs, i.e. instruct Emacs to display a buffer or file in
some specific manner that users of debuggers expect.  E.g., how would
you display breakpoint positions on the fringe?