bug#22519: 25.1.50; Emacs gets stuck while doing incremental search forward

[Vincent Belaïche]

Le 17/03/2016 à 17:20, Eli Zaretskii a écrit :
>> From: vincent.belaiche@gmail.com (Vincent Belaïche)
>> Cc: Vincent Belaïche <vincent.belaiche@gmail.com>,
>>   22519@debbugs.gnu.org
>> Date: Thu, 17 Mar 2016 10:14:04 +0100
>>

[...]

>
>> Would it be agreable if I make the following addition to the manual:
>
> I think this should be rewritten to go to etc/PROBLEMS instead of into
> the manual.

Ok, should I make this edit only for master branch, or for emacs-25
branch first & then merge it into master branch. In the latter case, it
would be helpful if you send me a pointer to instructions how to carry
out the merge with git.

FYI I have not tested that the bug is also there for emacs-25 branch, I
just can't imagine that it would not be there also.

VBR,
        Vincent.

PS: FYI, attached is patch to master branch.

>
> Thanks.

diff --git a/etc/PROBLEMS b/etc/PROBLEMS
index f61921a..39a5849 100644
--- a/etc/PROBLEMS
+++ b/etc/PROBLEMS
@@ -720,6 +720,20 @@ the following variables: tex-font-script-display (how much 
to
 lower/raise); tex-suscript-height-ratio (how much smaller than
 normal); tex-suscript-height-minimum (minimum height).
 
+** Screen refresh is slow when there are special characters for which no 
suitable font is available
+
+If the display is too slow in refreshing when you scroll to a new
+region, or when you edit the buffer, it may be due to this that some
+characters cannot be displayed in the default font, and Emacs is
+spending too much time in looking for a suitable font to display them.
+
+You can suspect this if you have several characters that are displayed
+as small rectangles containing a hexadecimal code inside.
+
+The solution is to install the appropriate fonts on your machine. For
+instance if you are editing a text with a lot of math symbols, then
+installing a font like 'Symbola' should solve this problem.
+
 * Internationalization problems
 
 ** M-{ does not work on a Spanish PC keyboard.