[Users] gdb output from latest claws-mail git showing a segfault

[Brian Morrison]

On Mon, 31 Mar 2025 09:19:45 +0300
Ivan Krylov via Users <users at lists.claws-mail.org> wrote:

> On Tue, 25 Mar 2025 13:27:59 +0000
> Brian Morrison via Users <users at lists.claws-mail.org> wrote:
> 
> > I have been suffering from a regular crash in Claws for a long
> > while, finally managed to get a backtrace.  
> 
> Unfortunately, this looks like heap corruption: something overwrote a
> pointer in the past (while parsing NNTP?), and now the program is
> crashing because of that. Would you be willing to compile Claws-Mail
> from source?

I will see what I can do, I build Claws using the Fedora spec file with
a few minor tweaks to cope with the git revision.

> If yes, it may be worth a try compiling it with
> sanitizers enabled:
> 
> LD_PRELOAD= ASAN_OPTIONS=detect_leaks=0 \
>  ./configure CC='gcc -fsanitize=address,undefined'
> # make as usual
> 
> You can then run it in a separate profile like so:
> 
> LD_PRELOAD= src/claws-mail --alternate-config-dir
> $HOME/.claws-alternate

OK, I will add this in to my spec file build section, see what I get
and will respond once I have something to add, this has been going on
for a long time so I am used to restarting Claws frequently :)

> 
> The "sanitizers" add safety checks around every pointer access.
> Hopefully one of them will catch the moment when the heap is
> corrupted. Unfortunately, this is not guaranteed to work: the memory
> corruption could be happening in a non-sanitised piece of code loaded
> into the process from outside. Valgrind may or may not help in that
> case (to be used on a normal build of Claws-Mail without sanitizers),
> but it comes at the cost of a significant slowdown.

Yes, I have used valgrind in the past, it is slow and maybe that will
not help if it is a timing-related problem.

> 
> Both sanitizers and Valgrind may complain about memory leaks. These
> are mostly due to libfontconfig, not Claws-Mail, and they wouldn't
> cause a crash.
> 


-- 

Brian Morrison

                "I am not young enough to know everything"
                                                          Oscar Wilde