SIGSEGV in `Tree.cellDataProc` when calling `TreeItem.setImage`

[torokati44]

Describe the bug

Virtual Tree widget crashes JVM (through GTK3) when setting Image onto TreeItem in Listener to SWT.SetData.
This is a continuation of https://bugs.eclipse.org/bugs/show_bug.cgi?id=573090.

---------------  T H R E A D  ---------------

Current thread (0x00007ffa500284a0):  JavaThread "main" [_thread_in_native, id=112372, stack(0x00007ffa57900000,0x00007ffa57a00000)]

Stack: [0x00007ffa57900000,0x00007ffa57a00000],  sp=0x00007ffa579fc318,  free space=1008k
Native frames: (J=compiled Java code, j=interpreted, Vv=VM code, C=native code)
C  [libgobject-2.0.so.0+0x3b251]  g_type_check_instance_is_fundamentally_a+0x11
C  [libswt-pi3-gtk-4958r2.so+0x4b609]  Java_org_eclipse_swt_internal_gtk_OS_g_1object_1set__J_3BJJ+0x4a

Java frames: (J=compiled Java code, j=interpreted, Vv=VM code)
J 11988  org.eclipse.swt.internal.gtk.OS.g_object_set(J[BJJ)V (0 bytes) @ 0x00007ffa491c5883 [0x00007ffa491c5820+0x0000000000000063]
J 10921 c1 org.eclipse.swt.widgets.Tree.cellDataProc(JJJJJ)J (486 bytes) @ 0x00007ffa419b8bf4 [0x00007ffa419b81e0+0x0000000000000a14]
J 10920 c1 org.eclipse.swt.widgets.Display.cellDataProc(JJJJJ)J (29 bytes) @ 0x00007ffa41f4ac5c [0x00007ffa41f4aa60+0x00000000000001fc]
v  ~StubRoutines::call_stub
J 11619  org.eclipse.swt.internal.gtk3.GTK3.gtk_main_iteration_do(Z)Z (0 bytes) @ 0x00007ffa49380e69 [0x00007ffa49380e20+0x0000000000000049]
J 11623 c1 org.eclipse.swt.widgets.Display.readAndDispatch()Z (88 bytes) @ 0x00007ffa423e622c [0x00007ffa423e6060+0x00000000000001cc]

To Reproduce

package swt_tree_crash;

import org.eclipse.swt.SWT;
import org.eclipse.swt.graphics.Image;
import org.eclipse.swt.layout.FillLayout;
import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.Event;
import org.eclipse.swt.widgets.Listener;
import org.eclipse.swt.widgets.Shell;
import org.eclipse.swt.widgets.Tree;
import org.eclipse.swt.widgets.TreeItem;

public class Main {
    public static void main(String[] args) {
        Display display = new Display();
        Shell shell = new Shell(display);
        shell.setLayout(new FillLayout());

        Tree tree = new Tree(shell, SWT.VIRTUAL);
        tree.addListener(SWT.SetData, new Listener() {
            public void handleEvent(final Event e) {
            	TreeItem item = (TreeItem)e.item;
                item.setText(0, "A");
                item.setImage(new Image(display, 20, 20)); // <-- this is the critical line!
            }
        });
        tree.setItemCount(1);
        
        shell.setSize(400, 300);
        shell.open();

        while (!shell.isDisposed()) {
            if (!display.readAndDispatch()) {
                display.sleep();
            }
        }
        display.dispose();
    }
}

Expected behavior

The application always shows a window with a tree widget in it, containing one item, with a small white icon.

Screenshots

Not applicable.

Environment:

1. Select the platform(s) on which the behavior is seen:

• • All OS
• • Windows
• • Linux
• • macOS

2. Additional OS info (e.g. OS version, Linux Desktop, etc)

Operating System: Fedora Linux 38
KDE Plasma Version: 5.27.4
KDE Frameworks Version: 5.105.0
Qt Version: 5.15.9
Kernel Version: 6.2.15-300.fc38.x86_64 (64-bit)
Graphics Platform: Wayland
Processors: 16 × AMD Ryzen 7 3800X 8-Core Processor
Memory: 31.2 GiB of RAM
Graphics Processor: AMD Radeon RX 550 Series

org.eclipse.swt.internal.gtk.version=3.24.37

3. JRE/JDK version

JRE version: OpenJDK Runtime Environment Temurin-17.0.7+7 (17.0.7+7) (build 17.0.7+7)
Java VM: OpenJDK 64-Bit Server VM Temurin-17.0.7+7 (17.0.7+7, mixed mode, tiered, compressed oops, compressed class ptrs, g1 gc, linux-amd64)

Version since

Tested on Eclipse 4.27 (SWT 4.958).

Workaround (or) Additional context

The crash doesn't always happen, but fairly often.
Removing the TreeItem.setImage call avoids the crash entirely.

[SyntevoAlex]

Sorry about the waiting time, SWT currently has few active maintainers.
I'm generally interested in JVM crashes, and plan to have a look at this eventually. Unfortunately the waiting time could be around a month.

[torokati44]

Hello, just a ping on this issue: We are still often encountering this crash on an almost daily basis... :/

[SyntevoAlex]

SWT is currently low on active contributors.
It would be nice if you can debug the problem yourself and prepare a fix.
Otherwise, alas, you'll have to wait more, and there's no ETA.

[torokati44]

Otherwise, alas, you'll have to wait more, and there's no ETA.

Of course, I understand, FOSS is what it is...

It would be nice if you can debug the problem yourself and prepare a fix.

Actually we ended up tossing the problematic pieces of code (in this one and #697) into a Display.asyncExec callback, so they can be done at a time when Gtk is hopefully no longer confused. It's dumb, but appears to be working so far.

[Mailaender]

I found a way to reproduce all the time in a @flatpak runtime, where also all workarounds fail.

[SyntevoAlex]

It would be useful if you describe how exactly do you reproduce.

[Mailaender]

Sorry, I thought that it won't be that helpful because you need to build a package to test.

Here it is https://github.com/Mailaender/flathub/compare/chemclipse Check the README for the commands to build it.

Click Demo on the green intro screen to trigger the crash.

Use

runtime-version: 20.08

and rebuild to see how the application looked before the crash was introduced.