[glib: 1/2] gobject: Mention quark memory usage for g_object_set_data()

[Sebastian Dröge <sdroege src gnome org>]

commit 2a570dc5af9becb4997468e9c51bddb1a6cc3404
Author: Philip Withnall <withnall endlessm com>
Date:   Thu Mar 7 10:56:47 2019 +0000

    gobject: Mention quark memory usage for g_object_set_data()
    
    g_object_set_data() should only ever be used with a small, bounded set
    of keys, or the memory usage of the quark lookup table will grow
    unbounded. Document that.
    
    Signed-off-by: Philip Withnall <withnall endlessm com>
    
    Fixes: #682

 gobject/gobject.c | 8 ++++++++
 1 file changed, 8 insertions(+)
---
diff --git a/gobject/gobject.c b/gobject/gobject.c
index 22c2cb39e..3095743c5 100644
--- a/gobject/gobject.c
+++ b/gobject/gobject.c
@@ -3629,6 +3629,11 @@ g_object_get_data (GObject     *object,
  *
  * If the object already had an association with that name,
  * the old association will be destroyed.
+ *
+ * Internally, the @key is converted to a #GQuark using g_quark_from_string().
+ * This means a copy of @key is kept permanently (even after @object has been
+ * finalized) — so it is recommended to only use a small, bounded set of values
+ * for @key in your program, to avoid the #GQuark storage growing unbounded.
  */
 void
 g_object_set_data (GObject     *object,
@@ -3707,6 +3712,9 @@ g_object_dup_data (GObject        *object,
  * or may not include using @old_destroy as sometimes replacement
  * should not destroy the object in the normal way.
  *
+ * See g_object_set_data() for guidance on using a small, bounded set of values
+ * for @key.
+ *
  * Returns: %TRUE if the existing value for @key was replaced
  *  by @newval, %FALSE otherwise.
  *