Segfault while trying to interact with UI when file is loading

[myrrc]

Sfizz version: latest master, also reproduced on 1.2.3 and 1.2.2
How to reproduce:

• Load a file in sfizz (either via zenity or with SFZ > browse without UI).
• Do not wait till this message

[sfizz] File changed to: ...
[sfizz] Number of masters: 2
[sfizz] Number of groups: 6
[sfizz] Number of regions: 220

• Try to interact with UI (e.g. press some button)

Message:

../../../src/cairo-xcb-screen.c:219: _get_screen_index: Assertion `!"reached"' failed.

Host: Reaper 7.15 on Debian 13.

Another way to reproduce (Reaper-specific):

• When plugin loaded, select "Window float selected FX". Plugin will tear down the window and then crash.
• (Alternative) Press "UI" button (toggle between native UI and Reaper's drawn UI) multiple times

I'll try to build sfizz-ui with debug info and provide detailed reports shortly

[myrrc]

#0  __pthread_kill_implementation (threadid=<optimized out>, signo=signo@entry=6, no_tid=no_tid@entry=0) at ./nptl/pthread_kill.c:44
#1  0x00007ffff799c1cf in __pthread_kill_internal (signo=6, threadid=<optimized out>) at ./nptl/pthread_kill.c:78
#2  0x00007ffff794e472 in __GI_raise (sig=sig@entry=6) at ../sysdeps/posix/raise.c:26
#3  0x00007ffff79384b2 in __GI_abort () at ./stdlib/abort.c:79
#4  0x00007ffff79383d5 in __assert_fail_base
    (fmt=0x7ffff7aacdc8 "%s%s%s:%u: %s%sAssertion `%s' failed.\n%n", assertion=assertion@entry=0x7ffff6c2e56f "!\"reached\"", file=file@entry=0x7ffff6c295d8 "../../../src/cairo-xcb-screen.c", line=line@entry=219, function=function@entry=0x7ffff6c3c990 "_get_screen_index") at ./assert/assert.c:92
#5  0x00007ffff79473a2 in __assert_fail
    (assertion=0x7ffff6c2e56f "!\"reached\"", file=0x7ffff6c295d8 "../../../src/cairo-xcb-screen.c", line=219, function=0x7ffff6c3c990 "_get_screen_index")
    at ./assert/assert.c:101
#6  0x00007ffff6bf418d in  () at /lib/x86_64-linux-gnu/libcairo.so.2
#7  0x00007ffff6bf68e3 in cairo_xcb_surface_create () at /lib/x86_64-linux-gnu/libcairo.so.2
#8  0x00007fffcdd8b9be in VSTGUI::X11::DrawHandler::DrawHandler(VSTGUI::X11::ChildWindow const&) (this=0x49bfca8, window=...)
    at /home/myrrc/src/sfizz-ui/plugins/editor/external/vstgui4/vstgui/lib/platform/linux/x11frame.cpp:171
#9  0x00007fffcdd8c424 in VSTGUI::X11::Frame::Impl::Impl(unsigned long, VSTGUI::CPoint, VSTGUI::IPlatformFrameCallback*)
    (this=0x49bfc80, parent=23072614, size=..., frame=0xe0c7140)
    at /home/myrrc/src/sfizz-ui/plugins/editor/external/vstgui4/vstgui/lib/platform/linux/x11frame.cpp:327
#10 0x00007fffcdd8aa26 in VSTGUI::X11::Frame::Frame(VSTGUI::IPlatformFrameCallback*, VSTGUI::CRect const&, unsigned int, VSTGUI::IPlatformFrameConfig*)
    (this=0xe10fb20, frame=0xe0c7140, size=..., parent=23072614, config=0x7fffffffc590, __in_chrg=<optimized out>, __vtt_parm=<optimized out>)
    at /home/myrrc/src/sfizz-ui/plugins/editor/external/vstgui4/vstgui/lib/platform/linux/x11frame.cpp:643
#11 0x00007fffcdd84d09 in VSTGUI::makeOwned<VSTGUI::X11::Frame, VSTGUI::IPlatformFrameCallback*&, VSTGUI::CRect const&, unsigned long&, VSTGUI::IPlatformFrameConfig*&>(VSTGUI::IPlatformFrameCallback*&, VSTGUI::CRect const&, unsigned long&, VSTGUI::IPlatformFrameConfig*&) ()
    at /home/myrrc/src/sfizz-ui/plugins/editor/external/vstgui4/vstgui/lib/platform/linux/../../vstguibase.h:469
#12 0x00007fffcdd83d22 in VSTGUI::LinuxFactory::createFrame(VSTGUI::IPlatformFrameCallback*, VSTGUI::CRect const&, void*, VSTGUI::PlatformType, VSTGUI::IPlatformFrameConfig*) const (this=0x7286be0, frame=0xe0c7140, size=..., parent=0x1600f66, parentType=VSTGUI::PlatformType::kDefaultNative, config=0x7fffffffc590)
    at /home/myrrc/src/sfizz-ui/plugins/editor/external/vstgui4/vstgui/lib/platform/linux/linuxfactory.cpp:96
#13 0x00007fffcdd3bca7 in VSTGUI::CFrame::open(void*, VSTGUI::PlatformType, VSTGUI::IPlatformFrameConfig*)
    (this=0xe0c7120, systemWin=0x1600f66, systemWindowType=VSTGUI::PlatformType::kDefaultNative, config=0x7fffffffc590)
    at /home/myrrc/src/sfizz-ui/plugins/editor/external/vstgui4/vstgui/lib/cframe.cpp:209
#14 0x00007fffcdc7a512 in instantiate(LV2UI_Descriptor const*, char const*, char const*, LV2UI_Write_Function, LV2UI_Controller, LV2UI_Widget*, LV2_Feature const* const*)
    (descriptor=0x7fffce106da0 <descriptor>, plugin_uri=0x7ffff4de3038 "http://sfztools.github.io/sfizz", bundle_path=0x4d55910 "/home/myrrc/.lv2/sfizz.lv2/", write_function=0xb76820, controller=0x578b960, widget=0x578cbb0, features=0x5795050) at /home/myrrc/src/sfizz-ui/plugins/lv2/sfizz_ui.cpp:292
#15 0x0000000000b76c59 in  ()
#16 0x0000000000b76f67 in  ()
#17 0x000000000081f85f in  ()
#18 0x0000000000824315 in  ()
#19 0x00000000007fad9e in  ()
#20 0x0000000000814367 in  ()
#21 0x00007ffff762b4d6 in  () at /opt/reaper/libSwell.so
#24 0x000000000040b04e in  ()
#25 0x00007ffff79396ca in __libc_start_call_main (main=main@entry=0x40a5b0, argc=argc@entry=1, argv=argv@entry=0x7fffffffe7f8)
    at ../sysdeps/nptl/libc_start_call_main.h:58
#26 0x00007ffff7939785 in __libc_start_main_impl
    (main=0x40a5b0, argc=1, argv=0x7fffffffe7f8, init=<optimized out>, fini=<optimized out>, rtld_fini=<optimized out>, stack_end=0x7fffffffe7e8)
    at ../csu/libc-start.c:360
#27 0x0000000000418b1a in _start ### ()

[myrrc]

I assume the bug is not in sfizz but the vstgui4 library. I'll try to investigate (there have been reports of crashes that I've linked)

[myrrc]

This issue also reproduces while building against latest vstgui from Steinberg

[paulfd]

This happened before, and it was at some point one of the reason for me to pin VSTGUI. I think we "had" to unpin it some time ago for other reasons. If I find some time I'll investigate, thanks for reporting.