3373 gcc >= 4.5 concerns about offsetof()

@@ -24,12 +24,10 @@
  */
 
 #ifndef _SA_STDDEF_H
 #define _SA_STDDEF_H
 
-#pragma ident   "%Z%%M% %I%     %E% SMI"
-
 /*
  * Exported interfaces for standalone's subset of libc's <stddef.h>.
  * All standalone code *must* use this header rather than libc's.
  */
 

@@ -40,11 +38,15 @@
 #ifndef NULL
 #define NULL    0
 #endif
 
 #ifndef offsetof
-#define offsetof(s, m)  (size_t)(&(((s *)0)->m))
+#if defined(__GNUC__)
+#define offsetof(s, m)  __builtin_offsetof(s, m)
+#else
+#define offsetof(s, m)  ((size_t)(&(((s *)0)->m)))
+#endif
 #endif
 
 #ifdef  __cplusplus
 }
 #endif