[GTK] Internal error loading image

[tmssngr]

Describe the bug
Loading a certain image fails on Ubuntu 26.04.

To Reproduce
Unpack the zip file with the image into the current directory (from the perspective of a running snippet) and run this snippet:

import java.io.*;
import java.nio.file.*;

import org.eclipse.swt.*;
import org.eclipse.swt.graphics.*;
import org.eclipse.swt.widgets.*;

public class ImageViewer {

	public static void main(String[] args) throws IOException {
		final Display display = new Display();

		final Image image;
		try (InputStream stream = Files.newInputStream(Paths.get("16-bits-channels.png"))) {
			final ImageData data = new ImageData(stream);
			image = new Image(display, data);
		}

		final Shell shell = new Shell(display);
		shell.addListener(SWT.Paint, event -> {
			event.gc.drawImage(image, 10, 10);
		});
		shell.setSize(400, 300);
		shell.open();

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

		image.dispose();

		display.dispose();
	}
}

16-bits-channels.png.zip
With the latest HEAD commit and a normal FullHD display with 100% scaling I'm getting this exception on Ubuntu 26.04 (Wayland):

Exception in thread "main" java.lang.IllegalArgumentException: Argument not valid
	at org.eclipse.swt.SWT.error(SWT.java:4915)
	at org.eclipse.swt.SWT.error(SWT.java:4849)
	at org.eclipse.swt.SWT.error(SWT.java:4820)
	at org.eclipse.swt.graphics.ImageData.<init>(ImageData.java:439)
	at org.eclipse.swt.graphics.ImageData.clone(ImageData.java:567)
	at org.eclipse.swt.internal.NativeImageLoader.load(NativeImageLoader.java:143)
	at org.eclipse.swt.graphics.ImageLoader.loadByZoom(ImageLoader.java:161)
	at org.eclipse.swt.graphics.ImageLoader.load(ImageLoader.java:154)
	at org.eclipse.swt.graphics.ImageDataLoader.load(ImageDataLoader.java:29)
	at org.eclipse.swt.graphics.ImageData.<init>(ImageData.java:334)
	at ImageViewer.main(ImageViewer.java:15)

Expected behavior
It should start - just like on Windows or Linux Mint (X11).

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)
   stock Ubuntu 26.04

[iloveeclipse]

Is this a recent regression?

[tmssngr]

Not very recent, as our customer reported it for SmartGit 25.1 which has been released 2025.