bug#26980: 25.2; Freeze & redisplay_internal & macOS

[Eli Zaretskii]

> From: Robert Vojta <rvojta@me.com>
> Date: Thu, 18 May 2017 07:57:04 +0200
> 
> What I was doing when it freezes?
> 
>  * Scroll with mouse wheel
>  * Refactor namespace
>  * Simple typing clj code
>  * Git fetch
> 
> As you can see, basically whatever can trigger this issue.
> 
> SIGUSR2 generates backtrace and it always ends up in redisplay_internal. 
> Example:
> 
> > Debugger entered--Lisp error: (quit)
> >   redisplay_internal\ \(C\ function\)()
> 
> Another example:
> 
> > Debugger entered--entering a function:
> > * command-error-default-function((quit) "" nil)
> >   recursive-edit()
> >   debug(error (quit))
> >   ...
> >   linum-after-scroll(#<window 3 on *Backtrace*> 2215)
> >   redisplay_internal\ \(C\ function\)()
> 
> Would like to solve this issue, but don’t know how. What else I can provide 
> to make this report more useful?

Please attach GDB to a freezing Emacs and show the C-level backtrace.
That will show more information, specifically below
redisplay_internal.