[glib] gobject/gtype.c: Emphasize use of priv in member and use g_return_val_if_fail

[Javier JardÃn <jjardon src gnome org>]

commit cb0566eaf3b245bf2eaa8c9e912cf240d8868193
Author: Christian Dywan <christian twotoasts de>
Date:   Sat Mar 26 14:48:54 2011 +0000

    gobject/gtype.c: Emphasize use of priv in member and use g_return_val_if_fail
    
    Fixes: https://bugzilla.gnome.org/show_bug.cgi?id=597785
    
    Signed-off-by: Javier JardÃn <jjardon gnome org>

 gobject/gtype.c |    8 +++++++-
 1 files changed, 7 insertions(+), 1 deletions(-)
---
diff --git a/gobject/gtype.c b/gobject/gtype.c
index 3732f7f..e9ed7fa 100644
--- a/gobject/gtype.c
+++ b/gobject/gtype.c
@@ -4408,6 +4408,8 @@ g_type_init (void)
  * <structname>MyObject</structname> defined in the standard GObject
  * fashion.
  * type's class_init() function.
+ * Note the use of a structure member "priv" to avoid the overhead
+ * of repeatedly calling MY_OBJECT_GET_PRIVATE().
  *
  * |[
  * typedef struct _MyObject        MyObject;
@@ -4440,7 +4442,11 @@ g_type_init (void)
  * static int
  * my_object_get_some_field (MyObject *my_object)
  * {
- *   MyObjectPrivate *priv = my_object->priv;
+ *   MyObjectPrivate *priv;
+ *
+ *   g_return_val_if_fail (MY_IS_OBJECT (my_object), 0);
+ *
+ *   priv = my_object->priv;
  *
  *   return priv->some_field;
  * }