Using LiveChart.ThresholdLine causes critical message for null access

[ryonakano]

Summary

Using LiveChart.ThresholdLine in the code outputs the following critical message on terminal:

** (Application:111411): CRITICAL **: 21:09:11.664: gee_abstract_collection_foreach: assertion 'self != NULL' failed

Steps to Reproduce

1. Save the following code with the name Application.vala:

Code Snippet

public class App : Gtk.Application {
    public App () {
        Object (
            application_id: "com.github.ryonakano.test",
            flags: ApplicationFlags.DEFAULT_FLAGS
        );
    }

    protected override void activate () {
        var window = new Gtk.ApplicationWindow(this);
        var chart = new LiveChart.Chart();

        var serie = new LiveChart.Serie("threshold", new LiveChart.ThresholdLine(200.0));
        chart.add_serie(serie);

        window.set_child(chart);
        window.present();
    }
}

public static int main (string[] args) {
    return new App ().run ();
}

2. Compile the code with valac --pkg gtk4 --pkg livechart --pkg gee-0.8 --debug Application.vala
3. Run the code with ./Application
4. See the critical message

Expected Behavior

No critical message is shown.

GDB Stack Trace

[ryo@lb760m ~/work/tmp/test]$ G_DEBUG=fatal-criticals gdb ./Application
GNU gdb (Fedora Linux) 14.1-4.fc39
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Reading symbols from ./Application...
(gdb) r
Starting program: /home/ryo/work/tmp/test/Application

This GDB supports auto-downloading debuginfo from the following URLs:
  <https://debuginfod.fedoraproject.org/>
Enable debuginfod for this session? (y or [n]) y
Debuginfod has been enabled.
To make this setting permanent, add 'set debuginfod enabled on' to .gdbinit.
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib64/libthread_db.so.1".
[New Thread 0x7fffe84006c0 (LWP 113062)]
[New Thread 0x7fffe7a006c0 (LWP 113063)]
[New Thread 0x7fffe70006c0 (LWP 113064)]
[New Thread 0x7fffe66006c0 (LWP 113065)]
[Thread 0x7fffe66006c0 (LWP 113065) exited]
[New Thread 0x7fffe66006c0 (LWP 113066)]
[New Thread 0x7fffe4a006c0 (LWP 113067)]

** (Application:113057): CRITICAL **: 21:18:48.391: gee_abstract_collection_foreach: assertion 'self != NULL' failed

Thread 1 "Application" received signal SIGTRAP, Trace/breakpoint trap.
g_logv (log_domain=0x0, log_level=G_LOG_LEVEL_CRITICAL, format=<optimized out>, args=args@entry=0x7fffffffd6c0) at ../glib/gmessages.c:1423
1423            g_private_set (&g_log_depth, GUINT_TO_POINTER (depth));
(gdb) bt
#0  g_logv (log_domain=0x0, log_level=G_LOG_LEVEL_CRITICAL, format=<optimized out>, args=args@entry=0x7fffffffd6c0)
    at ../glib/gmessages.c:1423
#1  0x00007ffff7092463 in g_log
    (log_domain=log_domain@entry=0x0, log_level=log_level@entry=G_LOG_LEVEL_CRITICAL, format=format@entry=0x7ffff70fa280 "%s: assertion '%s' failed") at ../glib/gmessages.c:1461
#2  0x00007ffff70936dd in g_return_if_fail_warning
    (log_domain=log_domain@entry=0x0, pretty_function=pretty_function@entry=0x7ffff7ef2340 <__func__.18.lto_priv.0> "gee_abstract_collection_foreach", expression=expression@entry=0x7ffff7ef0d49 "self != NULL") at ../glib/gmessages.c:2930
#3  0x00007ffff7e78401 in gee_abstract_collection_foreach (self=<optimized out>, f=<optimized out>, f_target=<optimized out>)
    at /usr/src/debug/libgee-0.20.6-3.fc39.x86_64/gee/abstractcollection.c:269
#4  0x00007ffff7f6133d in live_chart_series_register (self=0x5033e0, serie=0x580b80) at ../src/series.vala:19
#5  0x00007ffff7f439ff in live_chart_chart_add_serie (self=0x522a70, serie=0x580b80) at ../src/chart.vala:47
Python Exception <class 'gdb.error'>: value has been optimized out
(gdb)

Versions

• live-chart: latest master branch (ecd23aa9ba110412cf433428e9e8680e4428e2eb)
• OS: Fedora Linux 39 (Workstation Edition)
• gtk4-devel: 4.12.5
• libgee-devel: 0.20.6
• Vala: 0.56.14