Subject: Re: bug#34138: 27.0.50; Delayed display of PDF file images

From: Stephen Berman <[email-masked]>
Date: Sun, 20 Jan 2019 17:31:13 +0100

On Sun, 20 Jan 2019 18:08:05 +0200 Eli Zaretskii <[email-masked]> wrote:

>> From: Stephen Berman <[email-masked]>
>> Cc: [email-masked], [email-masked], [email-masked],
>> [email-masked]
>> Date: Sun, 20 Jan 2019 16:51:41 +0100
>> 
>> That makes sense.  (Actually, I had mentioned keyboard input with
>> reference to pdf-view-mode, where the delay is quite long; with
>> doc-view-mode the delay is only a few seconds, so I hadn't try using the
>> keyboard, but now I did and it did in fact then immediately switch to
>> the "Welcome to DocView!" display briefly before displaying the image,
>> so keyboard input appears to have an effect with doc-view-mode as well.)
>> 
>> > If you configure blink-cursor-mode to never stop blinking, does the
>> > problem go away, per chance?
>> 
>> No, that made no difference either with doc-view-mode or with
>> pdf-view-mode.
>
> Hmm... can you attach the debugger to Emacs during that delay, and
> show both C backtrace and Lisp backtrace?

I'm not sure what "attach the debugger to Emacs during that delay"
means, but what I did is to start emacs under gdb with my
initializations, then I opened a PDF file in pdf-view-mode, it showed
the raw PDF, at which point I typed C-z in gdb, then bt, then
xbacktrace, which showed nothing, then c, upon which the PDF image was
immediately shown, then I called bt again, but it looks like the same
backtrace, and xbacktrace again returned nothing.  I've attached the
complete transcript.  If you wanted me to do something else, please give
me step by step instructions.

Steve