glib r6996 - in trunk: . glib

[sdroege svn gnome org]

Author: sdroege
Date: Wed Jun 11 07:37:45 2008
New Revision: 6996
URL: http://svn.gnome.org/viewvc/glib?rev=6996&view=rev

Log:
Bug 531900 â Use __builtin_offsetof for G_STRUCT_OFFSET if building
with gcc 4.0 or newer
* glib/gmacros.h: Use __builtin_offsetof for G_STRUCT_OFFSET if
building with gcc 4.0 or newer.


Modified:
   trunk/ChangeLog
   trunk/glib/gmacros.h

Modified: trunk/glib/gmacros.h
==============================================================================
--- trunk/glib/gmacros.h	(original)
+++ trunk/glib/gmacros.h	Wed Jun 11 07:37:45 2008
@@ -209,8 +209,15 @@
 /* Provide convenience macros for handling structure
  * fields through their offsets.
  */
-#define G_STRUCT_OFFSET(struct_type, member)	\
-    ((glong) ((guint8*) &((struct_type*) 0)->member))
+
+#if defined(__GNUC__)  && __GNUC__ >= 4
+#  define G_STRUCT_OFFSET(struct_type, member) \
+      ((glong) __builtin_offsetof (struct_type, member))
+#else
+#  define G_STRUCT_OFFSET(struct_type, member)	\
+      ((glong) ((guint8*) &((struct_type*) 0)->member))
+#endif
+
 #define G_STRUCT_MEMBER_P(struct_p, struct_offset)   \
     ((gpointer) ((guint8*) (struct_p) + (glong) (struct_offset)))
 #define G_STRUCT_MEMBER(member_type, struct_p, struct_offset)   \