docs: Add missing GTK_ACCESSIBLE_VALUE_UNDEFINED

diff --git a/gtk/gtkenums.h b/gtk/gtkenums.h
index b0c7b9430d194053a2eac691157e21edc46b42c1..83fb4c645e9249bbd17b6962768a6a50626d3c07 100644 (file)
--- a/gtk/gtkenums.h
+++ b/gtk/gtkenums.h
@@ -1368,6 +1368,12 @@ typedef enum {
   GTK_ACCESSIBLE_STATE_SELECTED
 } GtkAccessibleState;
 
+/**
+ * GTK_ACCESSIBLE_VALUE_UNDEFINED:
+ *
+ * An undefined value. The accessible attribute is either unset, or its
+ * value is undefined.
+ */
 #define GTK_ACCESSIBLE_VALUE_UNDEFINED  (-1)
 
 /**