Re: Crash when using scroll bar in Carbon port (keyboard.c:3010)

[David Reitter]

On Jan 7, 9:30 am, YAMAMOTO Mitsuharu <mituh...@math.s.chiba-u.ac.jp>
wrote:

> Does this mean the problem also occurs with the (unmodified) Carbon
> port of Emacs 22?

Probably not, given that the bug seems to depend on frame parameters
being modified in after-change-major-mode-hook, as is done by
`aquamacs-styles-mode'.

> (Note thatAquamacsEmacs and Carbon Emacs Package
> have some modifications in common, so even if the problem happens on
> both of them, that does not necessarily imply that it is a bug in
> Carbon Emacs.

Likewise, if the bug has only been reproduced in one of them, it
doesn't mean that it is a bug in these distributions. It's a crash,
and pure ELisp code should never crash Emacs. Of course it could be a
bug in one of the patches to the C core.
This one is a bit difficult to home in on. Chances are there is a
problem with the code that sets the frame's parameters (but that
shouldn't lead to a crash).

> If so, could you describe the concrete step-by-step procedure to
> reproduce the problem?  For example, `scrolls around a buffer with the
> scroll bar' in the original report is not sufficiently concrete
> because there are multiple ways to scroll the window using the scroll
> bar (i.e., dragging the thumb, clicking above or below the thumb,
> clicking arrows).

It was enough to visit the .Rnw file (as added below in this e-mail),
resize the frame so that there is a vertical scroll bar and one can
scroll around, and then drag the thumb back and forth.

The OP has since added that scrolling with the mouse wheel alone, with
the scroll bar hidden, avoids the bug.

I found that scrolling with the keys or the mouse wheel generally
avoids reproduce the bug, and clicking above and below the thumb
doesn't bring it up either. It's only if you drag it (keep dragging up
and down).

- David


===
Hank Stevens wrote:
Hi folks,
I reported previously crashes when I used the scrollbar to move
quickly around .Rnw documents that include both LaTeX and R code. Of
course the problem didn't arise if I never used the scrollbar, but
that prevented me from moving quickly through long files. My work
around has been to hide the scrollbar (to prevent old habits) and to
rely on the mouse "wheel" in the new Mac mouse. It works very
nicely.
I suppose there must also be a quick keystroke that would allow me
to
page through a long file, but I don't know it but would like to know
what it is.

Thanks for all your efforts,
Hank



---
test.Rnw:

\documentclass{article}

\SweaveOpts{eval=true, echo=true}

%

\begin{document}

type stuff here.

Switch to R
<<>>=
2+2
@
Switch back to latex.
\end{document}