Please always post backtraces with reporting crashes

Hi Antonio, thank you for fast reaction and good luck

[daniel@frisee ~]$ coredumpctl gdb -1
PID: 42822 (guitarix)
UID: 1000 (daniel)
GID: 1000 (daniel)
Signal: 11 (SEGV)
Timestamp: Mon 2023-11-06 10:57:27 CET (23s ago)
Command Line: guitarix
Executable: /usr/bin/guitarix
Control Group: /user.slice/user-1000.slice/session-1.scope
Unit: session-1.scope
Slice: user-1000.slice
Session: 1
Owner UID: 1000 (daniel)
Boot ID: ebfb84a1f85a47a8bfab2fc35e240dfa
Machine ID: f6b265e8adbc467f84819759c66919f1
Hostname: frisee
Storage: /var/lib/systemd/coredump/core.guitarix.1000.ebfb84a1f85a47a8bfab2fc35e240dfa.42822.1699264647000000.zst (present)
Size on Disk: 2.4M
Message: Process 42822 (guitarix) of user 1000 dumped core.

Stack trace of thread 42829:
#0 0x00007f5c82eb7d12 FcRuleDestroy (libfontconfig.so.1 + 0x2ad12)
#1 0x00007f5c82ec0751 n/a (libfontconfig.so.1 + 0x33751)
#2 0x00007f5c821ec63f n/a (libexpat.so.1 + 0xd63f)
#3 0x00007f5c821e9c14 n/a (libexpat.so.1 + 0xac14)
#4 0x00007f5c821eb7ed n/a (libexpat.so.1 + 0xc7ed)
#5 0x00007f5c821ef8ea XML_ParseBuffer (libexpat.so.1 + 0x108ea)
#6 0x00007f5c82eba945 n/a (libfontconfig.so.1 + 0x2d945)
#7 0x00007f5c82ebb297 n/a (libfontconfig.so.1 + 0x2e297)
#8 0x00007f5c82ebb47a n/a (libfontconfig.so.1 + 0x2e47a)
#9 0x00007f5c82ea31a8 n/a (libfontconfig.so.1 + 0x161a8)
#10 0x00007f5c82e9e15d n/a (libfontconfig.so.1 + 0x1115d)
#11 0x00007f5c82ea348d FcInit (libfontconfig.so.1 + 0x1648d)
#12 0x00007f5c82ee5412 n/a (libpangoft2-1.0.so.0 + 0x9412)
#13 0x00007f5c85b079f5 n/a (libglib-2.0.so.0 + 0x8b9f5)
#14 0x00007f5c83caa9eb n/a (libc.so.6 + 0x8c9eb)
#15 0x00007f5c83d2e7cc n/a (libc.so.6 + 0x1107cc)

Stack trace of thread 42822:
#0 0x00007f5c83d2c73d syscall (libc.so.6 + 0x10e73d)
#1 0x00007f5c85b2f2b7 g_cond_wait (libglib-2.0.so.0 + 0xb32b7)
#2 0x00007f5c82ee9524 pango_fc_font_map_get_config (libpangoft2-1.0.so.0 + 0xd524)
#3 0x00007f5c84503237 n/a (libpangocairo-1.0.so.0 + 0x6237)
#4 0x00007f5c82ee9b7e n/a (libpangoft2-1.0.so.0 + 0xdb7e)
#5 0x00007f5c844b1586 n/a (libpango-1.0.so.0 + 0x1e586)
#6 0x00007f5c844c58b6 n/a (libpango-1.0.so.0 + 0x328b6)
#7 0x00007f5c844ba53f n/a (libpango-1.0.so.0 + 0x2753f)
#8 0x00007f5c844be2a8 pango_layout_get_pixel_extents (libpango-1.0.so.0 + 0x2b2a8)
#9 0x00007f5c85cb4f04 _gx_regler_calc_size_request (libgxw.so.0 + 0x12f04)
#10 0x00007f5c85cc245e n/a (libgxw.so.0 + 0x2045e)
#11 0x00007f5c85cc258d n/a (libgxw.so.0 + 0x2058d)
#12 0x00007f5c852925a0 n/a (libgtk-3.so.0 + 0x2925a0)
#13 0x00007f5c85292d00 gtk_widget_get_preferred_height_and_baseline_for_width (libgtk-3.so.0 + 0x292d00)
#14 0x00007f5c8538da7e n/a (libgtk-3.so.0 + 0x38da7e)
#15 0x00007f5c852925a0 n/a (libgtk-3.so.0 + 0x2925a0)
#16 0x00007f5c85292d00 gtk_widget_get_preferred_height_and_baseline_for_width (libgtk-3.so.0 + 0x292d00)
#17 0x00007f5c851aafd6 n/a (libgtk-3.so.0 + 0x1aafd6)
#18 0x00007f5c851ab5c1 n/a (libgtk-3.so.0 + 0x1ab5c1)
#19 0x00007f5c8510ad27 n/a (libgtk-3.so.0 + 0x10ad27)
#20 0x00007f5c851128f8 n/a (libgtk-3.so.0 + 0x1128f8)
#21 0x00007f5c851a755a n/a (libgtk-3.so.0 + 0x1a755a)
#22 0x00007f5c852925a0 n/a (libgtk-3.so.0 + 0x2925a0)
#23 0x00007f5c85292d00 gtk_widget_get_preferred_height_and_baseline_for_width (libgtk-3.so.0 + 0x292d00)
#24 0x00007f5c850bed9d n/a (libgtk-3.so.0 + 0xbed9d)
#25 0x00007f5c8510ad27 n/a (libgtk-3.so.0 + 0x10ad27)
#26 0x00007f5c851128f8 n/a (libgtk-3.so.0 + 0x1128f8)
#27 0x00007f5c850b64da n/a (libgtk-3.so.0 + 0xb64da)
#28 0x00007f5c852925a0 n/a (libgtk-3.so.0 + 0x2925a0)
#29 0x00007f5c85292d00 gtk_widget_get_preferred_height_and_baseline_for_width (libgtk-3.so.0 + 0x292d00)
#30 0x00007f5c850bed9d n/a (libgtk-3.so.0 + 0xbed9d)
#31 0x00007f5c8510ad27 n/a (libgtk-3.so.0 + 0x10ad27)
#32 0x00007f5c851128f8 n/a (libgtk-3.so.0 + 0x1128f8)
#33 0x00007f5c850b64da n/a (libgtk-3.so.0 + 0xb64da)
#34 0x00007f5c852925a0 n/a (libgtk-3.so.0 + 0x2925a0)
#35 0x00007f5c85292d00 gtk_widget_get_preferred_height_and_baseline_for_width (libgtk-3.so.0 + 0x292d00)
#36 0x00007f5c850bed9d n/a (libgtk-3.so.0 + 0xbed9d)
#37 0x00007f5c8510ad27 n/a (libgtk-3.so.0 + 0x10ad27)
#38 0x00007f5c851128f8 n/a (libgtk-3.so.0 + 0x1128f8)
#39 0x00007f5c850b6537 n/a (libgtk-3.so.0 + 0xb6537)
#40 0x00007f5c85291f4a n/a (libgtk-3.so.0 + 0x291f4a)
#41 0x00007f5c85292d00 gtk_widget_get_preferred_height_and_baseline_for_width (libgtk-3.so.0 + 0x292d00)
#42 0x00007f5c850bed9d n/a (libgtk-3.so.0 + 0xbed9d)
#43 0x00007f5c8510ad27 n/a (libgtk-3.so.0 + 0x10ad27)
#44 0x00007f5c851128f8 n/a (libgtk-3.so.0 + 0x1128f8)
#45 0x00007f5c850b64da n/a (libgtk-3.so.0 + 0xb64da)
#46 0x00007f5c852925a0 n/a (libgtk-3.so.0 + 0x2925a0)
#47 0x00007f5c85292d00 gtk_widget_get_preferred_height_and_baseline_for_width (libgtk-3.so.0 + 0x292d00)
#48 0x00007f5c850bed9d n/a (libgtk-3.so.0 + 0xbed9d)
#49 0x00007f5c8510ad27 n/a (libgtk-3.so.0 + 0x10ad27)
#50 0x00007f5c851128f8 n/a (libgtk-3.so.0 + 0x1128f8)
#51 0x00007f5c850b64da n/a (libgtk-3.so.0 + 0xb64da)
#52 0x00007f5c852925a0 n/a (libgtk-3.so.0 + 0x2925a0)
#53 0x00007f5c85292d00 gtk_widget_get_preferred_height_and_baseline_for_width (libgtk-3.so.0 + 0x292d00)
#54 0x00007f5c850bed9d n/a (libgtk-3.so.0 + 0xbed9d)
#55 0x00007f5c8510ad27 n/a (libgtk-3.so.0 + 0x10ad27)
#56 0x00007f5c851128f8 n/a (libgtk-3.so.0 + 0x1128f8)
#57 0x00007f5c850b64da n/a (libgtk-3.so.0 + 0xb64da)
#58 0x00007f5c852925a0 n/a (libgtk-3.so.0 + 0x2925a0)
#59 0x00007f5c85292d00 gtk_widget_get_preferred_height_and_baseline_for_width (libgtk-3.so.0 + 0x292d00)
#60 0x00007f5c850bed9d n/a (libgtk-3.so.0 + 0xbed9d)
#61 0x00007f5c8510ad27 n/a (libgtk-3.so.0 + 0x10ad27)
#62 0x00007f5c851128f8 n/a (libgtk-3.so.0 + 0x1128f8)
#63 0x00007f5c850b6537 n/a (libgtk-3.so.0 + 0xb6537)

Stack trace of thread 42824:
#0 0x00007f5c83d2c73d syscall (libc.so.6 + 0x10e73d)
#1 0x00007f5c85b2f2b7 g_cond_wait (libglib-2.0.so.0 + 0xb32b7)
#2 0x00007f5c85aa11b4 n/a (libglib-2.0.so.0 + 0x251b4)
#3 0x00007f5c85b09a7e n/a (libglib-2.0.so.0 + 0x8da7e)
#4 0x00007f5c85b079f5 n/a (libglib-2.0.so.0 + 0x8b9f5)
#5 0x00007f5c83caa9eb n/a (libc.so.6 + 0x8c9eb)
#6 0x00007f5c83d2e7cc n/a (libc.so.6 + 0x1107cc)

Stack trace of thread 42826:
#0 0x00007f5c83d20f6f __poll (libc.so.6 + 0x102f6f)
#1 0x00007f5c85b34276 n/a (libglib-2.0.so.0 + 0xb8276)
#2 0x00007f5c85ad6b97 g_main_loop_run (libglib-2.0.so.0 + 0x5ab97)
#3 0x00007f5c84f3914c n/a (libgio-2.0.so.0 + 0x11214c)
#4 0x00007f5c85b079f5 n/a (libglib-2.0.so.0 + 0x8b9f5)
#5 0x00007f5c83caa9eb n/a (libc.so.6 + 0x8c9eb)
#6 0x00007f5c83d2e7cc n/a (libc.so.6 + 0x1107cc)

Stack trace of thread 42828:
#0 0x00007f5c83ca74ae n/a (libc.so.6 + 0x894ae)
#1 0x00007f5c83cb2980 n/a (libc.so.6 + 0x94980)
#2 0x000055b01da891b1 _ZN9gx_engine8SCapture11disc_streamEv (guitarix + 0x2501b1)
#3 0x000055b01da892ef _ZN9gx_engine8SCapture10run_threadEPv (guitarix + 0x2502ef)
#4 0x00007f5c83caa9eb n/a (libc.so.6 + 0x8c9eb)
#5 0x00007f5c83d2e7cc n/a (libc.so.6 + 0x1107cc)

Stack trace of thread 42823:
#0 0x00007f5c83c5d3ca __sigtimedwait (libc.so.6 + 0x3f3ca)
#1 0x00007f5c83c5ca9c sigwait (libc.so.6 + 0x3ea9c)
#2 0x000055b01dba078c _ZN12PosixSignals20signal_helper_threadEv (guitarix + 0x36778c)
#3 0x00007f5c83ee1943 execute_native_thread_routine (libstdc++.so.6 + 0xe1943)
#4 0x00007f5c83caa9eb n/a (libc.so.6 + 0x8c9eb)
#5 0x00007f5c83d2e7cc n/a (libc.so.6 + 0x1107cc)

Stack trace of thread 42827:
#0 0x00007f5c83ca74ae n/a (libc.so.6 + 0x894ae)
#1 0x00007f5c83cb2980 n/a (libc.so.6 + 0x94980)
#2 0x000055b01da891b1 _ZN9gx_engine8SCapture11disc_streamEv (guitarix + 0x2501b1)
#3 0x000055b01da892ef _ZN9gx_engine8SCapture10run_threadEPv (guitarix + 0x2502ef)
#4 0x00007f5c83caa9eb n/a (libc.so.6 + 0x8c9eb)
#5 0x00007f5c83d2e7cc n/a (libc.so.6 + 0x1107cc)

Stack trace of thread 42825:
#0 0x00007f5c83d20f6f __poll (libc.so.6 + 0x102f6f)
#1 0x00007f5c85b34276 n/a (libglib-2.0.so.0 + 0xb8276)
#2 0x00007f5c85ad4162 g_main_context_iteration (libglib-2.0.so.0 + 0x58162)
#3 0x00007f5c85ad41b2 n/a (libglib-2.0.so.0 + 0x581b2)
#4 0x00007f5c85b079f5 n/a (libglib-2.0.so.0 + 0x8b9f5)
#5 0x00007f5c83caa9eb n/a (libc.so.6 + 0x8c9eb)
#6 0x00007f5c83d2e7cc n/a (libc.so.6 + 0x1107cc)
ELF object binary architecture: AMD x86-64

BTW, compiling from source did'nt succeed either, unfortunately. Report is on SourceForge.
Cheers
Daniel

Does from within gdb `thread apply all backtrace full` produce a backtrace with more symbols? I am assuming you allowed debuginfod [1] to fetch symbols? If you use the PKGBUILD [2] to build guitarix in a clean chroot [3] does that work?

[1]: https://wiki.archlinux.org/title/Debuginfod
[2]: https://wiki.archlinux.org/title/Arch_build_system#Usage
[3]: https://wiki.archlinux.org/title/DeveloperWiki:Building_in_a_clean_chroot

Hi Loqs, thank you for the advice. My bad. Now the result :

Program terminated with signal SIGSEGV, Segmentation fault.
#0 0x00007f90e1141d12 in FcRuleDestroy (rule=<optimized out>) at ../fontconfig/src/fcxml.c:89
Downloading source file /usr/src/debug/fontconfig/build/../fontconfig/src/fcxml.c
89 FcRule *n = rule->next;

Also, a hint towards a font problem is now printed (it did not appear previously) when starting guitarix:
[daniel@frisee ~]$ guitarix
Fontconfig error: "/usr/share/fontconfig/conf.avail/60-generic.conf", line 65: cannot get parse buffer
Segmentation fault (core dumped)

Is it a local problem in my fonts ?

Here is output from fc-cache -v

[daniel@frisee ~]$ fc-cache -v
Font directories:
/home/daniel/.local/share/fonts
/usr/local/share/fonts
/usr/share/fonts
/home/daniel/.fonts
/usr/share/fonts/100dpi
/usr/share/fonts/75dpi
/usr/share/fonts/OTF
/usr/share/fonts/TTF
/usr/share/fonts/adobe-source-code-pro
/usr/share/fonts/cantarell
/usr/share/fonts/encodings
/usr/share/fonts/frutiger
/usr/share/fonts/futura
/usr/share/fonts/garamond
/usr/share/fonts/gsfonts
/usr/share/fonts/liberation
/usr/share/fonts/misc
/usr/share/fonts/util
/usr/share/fonts/encodings/large
/home/daniel/.local/share/fonts: skipping, no such directory
/usr/local/share/fonts: skipping, no such directory
/usr/share/fonts: skipping, existing cache is valid: 0 fonts, 14 dirs
/usr/share/fonts/100dpi: skipping, existing cache is valid: 398 fonts, 0 dirs
/usr/share/fonts/75dpi: skipping, existing cache is valid: 398 fonts, 0 dirs
/usr/share/fonts/OTF: skipping, existing cache is valid: 23 fonts, 0 dirs
/usr/share/fonts/TTF: skipping, existing cache is valid: 48 fonts, 0 dirs
/usr/share/fonts/adobe-source-code-pro: skipping, existing cache is valid: 30 fonts, 0 dirs
/usr/share/fonts/cantarell: skipping, existing cache is valid: 6 fonts, 0 dirs
/usr/share/fonts/encodings: skipping, existing cache is valid: 0 fonts, 1 dirs
/usr/share/fonts/encodings/large: skipping, existing cache is valid: 0 fonts, 0 dirs
/usr/share/fonts/frutiger: skipping, existing cache is valid: 40 fonts, 0 dirs
/usr/share/fonts/futura: skipping, existing cache is valid: 15 fonts, 0 dirs
/usr/share/fonts/garamond: skipping, existing cache is valid: 10 fonts, 0 dirs
/usr/share/fonts/gsfonts: skipping, existing cache is valid: 35 fonts, 0 dirs
/usr/share/fonts/liberation: skipping, existing cache is valid: 12 fonts, 0 dirs
/usr/share/fonts/misc: skipping, existing cache is valid: 89 fonts, 0 dirs
/usr/share/fonts/util: skipping, existing cache is valid: 0 fonts, 0 dirs
/home/daniel/.fonts: skipping, no such directory
/usr/share/fonts/100dpi: skipping, looped directory detected
/usr/share/fonts/75dpi: skipping, looped directory detected
/usr/share/fonts/OTF: skipping, looped directory detected
/usr/share/fonts/TTF: skipping, looped directory detected
/usr/share/fonts/adobe-source-code-pro: skipping, looped directory detected
/usr/share/fonts/cantarell: skipping, looped directory detected
/usr/share/fonts/encodings: skipping, looped directory detected
/usr/share/fonts/frutiger: skipping, looped directory detected
/usr/share/fonts/futura: skipping, looped directory detected
/usr/share/fonts/garamond: skipping, looped directory detected
/usr/share/fonts/gsfonts: skipping, looped directory detected
/usr/share/fonts/liberation: skipping, looped directory detected
/usr/share/fonts/misc: skipping, looped directory detected
/usr/share/fonts/util: skipping, looped directory detected
/usr/share/fonts/encodings/large: skipping, looped directory detected
/var/cache/fontconfig: not cleaning unwritable cache directory
/home/daniel/.cache/fontconfig: cleaning cache directory
/home/daniel/.fontconfig: not cleaning non-existent cache directory
fc-cache: succeeded

When i tried to build from source i downloaded the code as is from SourceForge and followed the instructions. I don't have a PKGBUILD for this software.

output of 'pacman -Qkk fontconfig'?

[root@frisee daniel]# pacman -Qkk fontconfig
fontconfig: 355 total files, 0 altered files

[root@frisee daniel]# pacman -Qkk fontconfig
fontconfig: 355 total files, 0 altered files

Hi,
In the meanwhile i tested guitarix on two other Arch machines and it works like a charm there. Thus it looks like my font system is messed up. I wonder if there is a way to repair or uninstall/reinstall the font system (from a live system perhaps ?). Anyway obviously the guitarix package is not the culprit, and this task can be closed.
Many thanks for your kind attention on this issue.
Regards
Daniel