if and only if an Error message (was: Re: Emacs hangs with 100pc CPU during query-replace)

[Emanuel Berg <embe8573@student.uu.se>]

Emanuel Berg <embe8573@student.uu.se> writes:

>> If you "let Emacs do something" you really should
>> get a debugger with SIGUSR2.  E.g. try just to type
>> M-: or M-x and leave the minibuffer open.
>
> For me, it is the same there. But turns out, it is a
> configuration problem. With 'emacs -Q', it works as
> you say.

OK, that wasn't it, either.

The _first_ time I do it, namely

(progn
  (setq debug-on-quit t)
  (signal 'quit nil) )

it brings up the *Backtrace* buffer. Second time and
forever after, it is just "Quit" in the echo area. The
same actually for any error: for example,

(message 'not-a-string)

- first time the buffer, thereafter a message saying:

    eval: Wrong type argument: stringp, not-a-string

So the error doesn't have to be the same. Only the
first gets the backtrace. Even with `M-x debug' (which
shows the backtrace buffer), the new error(s) doesn't
seem to be documented there.

Isn't there like an *Errors* buffer were only error
messages gets stored, and all of them?

-- 
underground experts united