Subject: bug#47067: 28.0.50; [feature/native-comp] Crash while scrolling through dispnew.c

From: Eli Zaretskii <[email-masked]>
Date: Sun, 14 Mar 2021 10:02:19 +0200

> From: Andrea Corallo <[email-masked]>
> Cc: Eli Zaretskii <[email-masked]>, [email-masked]
> Date: Sun, 14 Mar 2021 07:19:17 +0000
> 
> Okay with a trunk gdb I'm able to debug...

Yes, 8.2 is quite an old version.

> Here is my backtrace for the suggested reproducer on my Emacs configured
> with --with-wide-int --enable-checking=yes,glyphs and compiled with the
> default `comp-debug' 0.

Thanks.  However, your build is optimized, whereas mine isn't.  This
has a significant effect on the backtrace (static functions are
inlined and don't appear in the backtrace).  Please reconfigure with
CFLAGS='-O0 -g3' (and the rest of the switches as you used them for
this build), and show the backtrace after rebuilding.

As I established earlier, in

  https://debbugs.gnu.org/cgi/bugreport.cgi?bug=47067#80
  https://debbugs.gnu.org/cgi/bugreport.cgi?bug=47067#83

the code which GDB fails to identify with any symbols calls Emacs
primitives via freloc.link_table.  Where is the C source for this
code?  If there is no C source, then how is that code generated?

> Emacs does not crash if then I continue and scroll through down through
> in the file.

And if you type "C-s sleep"?