Subject: bug#16526: 24.3.50; scroll-conservatively & c-mode regression

From: martin rudalics <[email-masked]>
Date: Thu, 30 Jan 2014 08:37:08 +0100

> I don't think this happens.  back_comment (in syntax.c) assumes it
 > starts outside a comment.

Does it?

 >> In any case, please provide an option say
 >> `c-open-paren-in-column-0-is-defun-start' which people can set to
 >> avoid those scans.  The doc-string should mention that things like
 >> Michael's commented out code are handled correctly iff this option is
 >> nil and that long delays while working with c-mode can be sometimes
 >> avoided by setting this option to t.  The default value could be
 >> obviously nil.
 >
 > I'm hoping that the (rough) patch in one of my other emails from this
 > evening will have solved the bug, so that playing around with
 > open-paren-in-column-0-etc. won't be needed.
 >
 > As a matter of interest, with my patch applied, running your recipe on
 > xdisp.c took me 4.4 seconds (including the (sit-for 3)).

Less than 8 seconds here which is quite remarkable.  Unfortunately, I
seem to have another problem now which makes `beginning-of-buffer' in
xdisp.c extremely slow with my setup (~ 30 secs).  Have to bisect my
.emacs again ...

Thanks so far, martin