Re: [Pan-users] pan always crashing fast again

[Duncan]

dchmelik-Re5JQEeQqe8AvxtiuMwx3w posted on Fri, 2 Sep 2022 19:37:53 -0700
as excerpted:

> Like for past few years until earlier this year, pan always crashes fast
> again (on Slackware64 15+current GNU/Linux).
> 
> Pan always says something like this before crashing: (pan:16759):

> Gtk-CRITICAL **: 19:23:47.724: IA__gtk_tree_view_column_set_fixed_width:
> assertion 'fixed_width > 0' failed

What version of pan (FWIW I'm running live-git-master pan at the commit 
shown in my headers, here)?  And do you know or can you check whether it's 
built against gtk2 or gtk3?  (If you can't check the package deps try 
running ldd /usr/bin/pan | grep gtk in a terminal, changing the path if 
appropriate of course.  Here I get libgtkspell3-3.so.0 and libgtk-3.so.0, 
so it's a gtk3 build, not gtk2.)

Until quite recently pan was built by default against gtk2, and that looks 
like a bug I had somewhat frequently with it.  However, while it *DID* 
mess up the UI, it did *not* crash pan, which would continue to run, just 
with the UI messed up (only showing one column in the overview/header 
pane).  So while you might have that bug too, it shouldn't be triggering 
the crash, just by coincidence happening before whatever does trigger the 
crash.

Meanwhile, gtk2 is being phased out and some distros don't even have it 
available any longer, so those it's quite likely a recent pan is built 
against gtk3.  The problem there is that only /quite/ recently were a 
number of critical gtk3 and other newer library bugs fixed (while pan has 
a new maintainer now, it was effectively frozen for a few years, during 
which it unfortunately got pretty stale against current libraries, and all 
those accumulated new-version ports and associated bugs took some time to 
fix), so unless you have a *really* new version, you're likely seeing a 
now fixed crash related to the first still-quite-buggy gtk3 and other 
library upgrade ports.

Pan version 0.151, "Butcha", was released in late June.  That should have 
most of the fixes and be pretty stable (tho a quick look says there's more 
than translations committed since then, but I'd say I've been stable since 
about then or a bit earlier), but given distro release cycles and the fact 
that (as a Gentooer) I don't know how current Slackware 15+current 
actually is, I'd say 50/50 you're on something before that, and the fact 
that you're still crashing increases the odds further, to I'd say 70/30 
that you're running something without those bugfixes.

Of course it could be a problem with a specific library you're running, 
too.  At least one of the problems I had for a few months was I suspect a 
gmime library issue.  I'm now stable but my gmime (3.2.13) was last 
updated Aug 22 (tho pan was stable for me somewhat before that, so it 
wasn't that version that fixed it for me) so...

Anyway, the most frustrating crashing bug I did have recently, from the 
switch to building to gtk3 until just a few months ago (sometime early 
this year), was somewhat reliably triggered by mouse-move over pan's body 
pane.  As long as I was very careful to keep the mouse away from the body 
pane, pan would normally stay running, and just a quick stray over the 
body pane often wouldn't trigger a crash either, but if I lingered and 
especially if I tried to scroll the body pane (which had been and is now 
again a habit, so I was doing it quite a bit... until this bug forced me 
out of the habit for a few months), it'd generally only be seconds until 
pan crashed.

Unfortunately for pinning down the fix, I learned to keep the mouse well 
away from the body pane for awhile, and only fairly recently discovered 
that mouse over the body pane didn't crash pan any longer, so I really 
don't know what fixed it, only that /something/, /maybe/ libgmime related 
(I know a couple other non-crash bugs were gmime related, not sure about 
this one), did indeed fix it, and I've not had a pan crash in some months 
now.

So assuming pan isn't crashing so fast you don't have the chance, try 
keeping the mouse out of the body pane and see if that helps it keep 
running.  If it does, you very likely have the same bug I did, and 
/something/ I updated recently fixed it.  If pan crashes before you get 
that far or when the mouse is elsewhere, you probably have a different 
bug.


-- 
Duncan - List replies preferred.   No HTML msgs.
"Every nonfree program has a lord, a master --
and if you use the program, he is your master."  Richard Stallman