[Bug awt/69629] New: GTK Toolkit notifies ImageObservers in cases where it shouldn't

[guillerodriguez.dev at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=69629

            Bug ID: 69629
           Summary: GTK Toolkit notifies ImageObservers in cases where it
                    shouldn't
           Product: classpath
           Version: 0.99
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: awt
          Assignee: unassigned at gcc dot gnu.org
          Reporter: guillerodriguez.dev at gmail dot com
  Target Milestone: ---

Created attachment 37555
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=37555&action=edit
Test program

There seems to be a bug in Classpath's AWT GTK toolkit in that ImageObservers
are notified when they shouldn't. In some cases this may result in an infinite
rendering loop.

The attached example shows this bug in action. The bug is triggered by the line
that gets the image width, passing a reference to the Component ("this") as the
ImageObserver:

    int w = img.getWidth(this);

According to the spec, the ImageObserver should only be notified when the width
is not yet known (i.e. when getWidth returns -1).