Re: Early backtrace.

[Stefan Monnier]

> So I came up with the following, which has no Lisp dependencies.  That
> is, absolutely none.  I have used it as the first Lisp file loaded,
> immediately before byte-run.el.

I have a similar hack here for the same reason ;-)
So a +1 from me (tho I'd recommend using the `debugger-` namespace
rather than `early-`).

> So, how about including this file in Emacs, amending eval.c to use it if
> backtrace.el isn't yet avaiable?  Comments and criticism are welcome.

I don't see any need for a change to `eval.c`.  Just put the

    (setq debugger #'early-debug)

and

    (setq debugger #'debug)

at the appropriate places inside `loadup.el`.


        Stefan