Merge branch 'weak-notify-dispose' into 'master'

Handle the case of g_object_run_dispose() in GBinding

Closes #2265

See merge request GNOME/glib!1786

gobject/gbinding.c

@@ -388,11 +388,30 @@ weak_unbind (gpointer  user_data,
   target = g_weak_ref_get (&context->target);
 
   /* If this is called then either the source or target or both must be in the
-   * process of being finalized and their weak reference must be reset to NULL
+   * process of being disposed. If this happens as part of g_object_unref()
-   * already.
+   * then the weak references are actually cleared, otherwise if disposing
+   * happens as part of g_object_run_dispose() then they would still point to
+   * the disposed object.
    *
-   * If source==target then both will always be NULL here. */
+   * If the object this is being called for is either the source or the target
-  g_assert (source == NULL || target == NULL);
+   * and we actually got a strong reference to it nonetheless (see above),
+   * then signal handlers and weak notifies for it are already disconnected
+   * and they must not be disconnected a second time. Instead simply clear the
+   * weak reference and be done with it.
+   *
+   * See https://gitlab.gnome.org/GNOME/glib/-/issues/2266 */
+
+  if (source == where_the_object_was)
+    {
+      g_weak_ref_set (&context->source, NULL);
+      g_clear_object (&source);
+    }
+
+  if (target == where_the_object_was)
+    {
+      g_weak_ref_set (&context->target, NULL);
+      g_clear_object (&target);
+    }
 
   binding_was_removed = unbind_internal_locked (context, binding, source, target);
 
@@ -627,10 +646,6 @@ g_binding_unbind_internal (GBinding *binding,
   source = g_weak_ref_get (&context->source);
   target = g_weak_ref_get (&context->target);
 
-  /* If the binding was removed previously, source and target are both NULL.
-   * Otherwise both will not be NULL. */
-  g_assert ((source == NULL && target == NULL) || (source != NULL && target != NULL));
-
   binding_was_removed = unbind_internal_locked (context, binding, source, target);
 
   g_mutex_unlock (&binding->unbind_lock);

gobject/gobject.c

@@ -2975,7 +2975,7 @@ weak_refs_notify (gpointer data)
  * @data: extra data to pass to notify
  *
  * Adds a weak reference callback to an object. Weak references are
- * used for notification when an object is finalized. They are called
+ * used for notification when an object is disposed. They are called
  * "weak references" because they allow you to safely hold a pointer
  * to an object without calling g_object_ref() (g_object_ref() adds a
  * strong reference, that is, forces the object to stay alive).

gobject/gobject.h

@@ -227,11 +227,11 @@ typedef void (*GObjectFinalizeFunc)     (GObject      *object);
 /**
  * GWeakNotify:
  * @data: data that was provided when the weak reference was established
- * @where_the_object_was: the object being finalized
+ * @where_the_object_was: the object being disposed
  * 
  * A #GWeakNotify function can be added to an object as a callback that gets
  * triggered when the object is finalized. Since the object is already being
- * finalized when the #GWeakNotify is called, there's not much you could do 
+ * disposed when the #GWeakNotify is called, there's not much you could do 
  * with the object, apart from e.g. using its address as hash-index or the like. 
  */
 typedef void (*GWeakNotify)		(gpointer      data,