Crash with VLC

[sebaro]

FVWM crashes when closing VLC whle playing a video or when the video finishes playing.
The issue is with Qt version not CLI.

git-bisect:

320ae7aa230106647246d7b19b83a4630956fc93 is the first bad commit
commit 320ae7aa230106647246d7b19b83a4630956fc93
Author: Dominik Vogt <dominik.vogt@gmx.de>
Date:   Fri Nov 26 21:41:37 2021 +0100

    Fix fvwm missing DestroyNotify events that died before reparenting.

 fvwm/add_window.c | 39 ++++++++++++++++++++++++++++++---------
 1 file changed, 30 insertions(+), 9 deletions(-)

[ThomasAdam]

Hi @sebaro

I can't reproduce this. If you compile fvwm3 with debug symbols, can you get a corefile and hence a backtrace for me to analyse?

[sebaro]

How do I get this? I tried with CFLAGS="-Og -g2 -ggdb" but this causes an issue with FvwmPager "malloc:zero size".

[ThomasAdam]

How do I get this? I tried with CFLAGS="-Og -g2 -ggdb" but this causes an issue with FvwmPager "malloc:zero size".

I would say:

make CFLAGS="-O0 -ggdb"

Don't worry about FvwmPager -- if that's really a problem we can fix it after the fact.

[sebaro]

With the latest git there's no crash with VLC but with the pager, when I open an app the pager disappears and on app minimize fvwm crashes.
Attached core dumps for 1.0.5 (vlc), git (pager):
core_.tar.gz

[ThomasAdam]

@sebaro

Those files you've sent through aren't corefiles -- so I can't use them.

So are you now saying that vlc no longer crashes, but FvwmPager does?

Please heed the bug report instructions next time -- it does ask you to try the git version of fvwm3 before reporting bugs.

[ThomasAdam]

Even with your new instructions, I can't make FvwmPager segfault.

Can you send me through your entire fvwm config, please?

[sebaro]

This is in the vlc core dump:

Core was generated by `fvwm3'.
Program terminated with signal SIGSEGV, Segmentation fault.
#0  0x00007f54e91f27ef in free () from /lib64/libc.so.6
(gdb) bt
#0  0x00007f54e91f27ef in free () from /lib64/libc.so.6
#1  0x00007f54ea13b959 in XFree () from /usr/lib64/libX11.so.6
#2  0x0000557bc16fab32 in AddWindow ()
#3  0x0000557bc16e13b5 in HandleMapRequestKeepRaised ()
#4  0x0000557bc16e358e in dispatch_event ()
#5  0x0000557bc16e444c in HandleEvents ()
#6  0x0000557bc16c0513 in main ()

I don't get this with the latest git, but two issues with FvwmPager and IconBox.

FvwmPager disappears when opening an app, the problem is this option:

*FvwmPager: WindowBorderWidth 0

IconBox crashes fvwm with these two options:

Style * IconBackgroundRelief 0
Style * IconBackgroundPadding 0

My config
https://gist.github.com/sebaro/81190adcea808358938eb14d6ec391a2

[ThomasAdam]

@sebaro

Regarding the FvwmPager issue, can you try the following:

diff --git a/libs/Graphics.c b/libs/Graphics.c
index 5bf7b6628..c929338aa 100644
--- a/libs/Graphics.c
+++ b/libs/Graphics.c
@@ -119,7 +119,7 @@ void do_relieve_rectangle_with_rotation(
        }
        max_w = min((w + 1) / 2, line_width);
        max_h = min((h + 1) / 2, line_width);
-       seg = fxmalloc(sizeof(XSegment) * line_width * 2);
+       seg = fxmalloc(sizeof(XSegment) * line_width * 2 + 1);
        /* from 0 to the lesser of line_width & just over half w */
 
        /* left */

When you say "IconBox crashes fvwm with these two options" -- what do you mean? IconBox is just an area for icons to reside when an application is iconified. Are you saying fvwm3 is crashing?

[sebaro]

The patch works.

When you say "IconBox crashes fvwm with these two options" -- what do you mean? IconBox is just an area for icons to reside when an application is iconified. Are you saying fvwm3 is crashing?

Yes, fvwm3 crashes when I minimize/iconify apps. Commenting the "IconBackground" style options fixes this issue.
Edit: IconBox it's fine now, maybe related to the pager issue.