RE: Emacs hangs with 100pc CPU during query-replace

[Drew Adams]

> > One more question: the backtraces I get contain ascii-control characters
> > - how can I copy/insert them into an email with these chars replaced (by
> > their string representation -> ^K e.g.)?
> 
> You shouldn't bother, as those characters are not helpful anyway.
> 
> If you want to produce a more helpful backtrace, manually load each
> library as .el file, then the backtrace will not include byte code.

Yes, as Eli says, loading source code provides a more helpful
backtrace (more and better information).  And yes, characters
introduced by byte code are not helpful/useful.

But see Emacs bug #6991:
http://debbugs.gnu.org/cgi/bugreport.cgi?bug=6991/

This is what jidanni reported in #6991:

  Please keep bytecode out of *Backtrace* buffers.
  * It is unreadable.
  * It will cause problems when sent via email. Even if one runs
    col(1) and strings(1) on it, nobody can read it anyway.
  * The mountain of gobbledygook makes people reading give up on
    trying to help. E.g., http://article.gmane.org/gmane.emacs.w3m/8695

Emacs users should be able to paste a backtrace that does contain
byte-code chars, and have those chars elided or removed, rather
than have the pasted text be truncated at some point because of
a byte-code char.

IOW, users should not need to fiddle with a backtrace to try to
piece together its non byte-code parts when trying to report it.

In addition, it is not very practical to ask users to find and
load each and every source file that might contribute to a backtrace.
Especially if the trace appeared because of `debug-on-error' and it
might not be easy to reproduce the error.

And even if only source code is loaded, there can be some code
parts that are byte-compiled (programmatically).  Byte-compiling
is not limited to a whole file.

No reason was given for not fixing bug #6991, or even for keeping
it open but relegating it to the `wishlist' until someone can get
around to fixing it.  What was the response to jidanni's bug filing?
This one-liner:

  From: Glenn Morris
  No. Closed as wontfix.

That is not very helpful.

With some struggle, we eventually got the `wontfix' tag removed, the
bug moved to `wishlist' and tagged `patch' (Stefan provided a patch
that he says does not work for him).  But other than that, no progress.