Re: git+master: c6e6503900534d939dd94b812563c27f22c49b7d crash when using gnus

[Eli Zaretskii <eliz@gnu.org>]

> From: Uwe Brauer <oub@mat.ucm.es>
> Cc: Uwe Brauer <oub@mat.ucm.es>, emacs-devel@gnu.org
> Date: Sat, 28 Apr 2018 13:56:28 +0200
> 
>    > Basically, start GDB with Emacs as the executable to debug, then run
>    > Emacs from GDB's command line.
> 
> 
> Oh well,
> 
> I tried gdb /opt/emacs27/bin/emacs
> and I obtained
> Reading symbols from /opt/emacs27/bin/emacs...(no debugging symbols
> found)...done.

Your Emacs was not built with debugging symbols.  The "Preliminaries"
section of etc/DEBUG explains how to build with debugging symbols.

> But no emacs started.

Because you didn't start it.  The GDB "run" command starts the
executable.  This is again described in etc/DEBUG.

> The message indicates that I should recompile emacs?

Yes.

>    > No need to google, the answer is under your fingertips: see the
>    > beginning of the file etc/DEBUG in the Emacs source tree.
> 
> Thanks, but just read it, but it is a bit confusing, since it is not
> clear to me whether I could start emacs first and then start gdb within
> emacs.

You can either start GDB from (another session of) Emacs, or start GDB
from the shell prompt.  In both cases, you should then start Emacs
from GDB.

> So shall I recompile emacs with debug options like
> 
>   CFLAGS='-O0 -g3' ./configure --enable-checking='yes,glyphs' --enable-check-lisp-object-type

Yes, that's a good beginning.