bug#17301: 24.3.90; Hang using scroll bar thumb in Compile-Log buffer after packages update

[N. Jackson]

At 16:44 -0300 on Sunday 2014-04-20, Jarek Czekalski wrote:

> Could be the bug with a patch waiting for months, marked important:
> http://debbugs.gnu.org/cgi/bugreport.cgi?bug=15801
>
> Jarek

Yes. Reading bug 15801, this seems to be the same thing.

The immediate question that occurred to me was why would it suddenly
manifest in the pretest when I haven't seen it once in the past
year. And the answer might be simple: I don't normally use the
mouse. For about a year I've been working exclusively on GNU Linux
systems and I interact with them using the keyboard. But during the last
couple of weeks I've been working at a job where we use Windows machines
and all my old mousing habits have come flooding back! Today might quite
possibly be the first time I've used a scrolling thumb in Emacs.

Inspired by the original bug report for bug 15801 I scrolled the Gnus
summary buffer up and down a few times with the scrolling thumb and
almost immediately hung Emacs 24.3.50 built from trunk in late February
(revision: 116611).

So I can hang the pretest and 24.3.50 moderately easily. (I did a few
tests and it doesn't always hang quite so fast as in the first two
cases, but it does after a bit).

I haven't been able to get Emacs 24.3.1 (x86_64-redhat-linux-gnu, GTK+
Version 3.8.2) of 2013-08-14 to hang in this way, but I'm not sure
whether it's because I was insufficiently persistent or if it doesn't
have the bug.