gcc-you can use this code to learn something about gcc, and inquire further into linux,

				// `B::a' contains empty classes which may cause base classes to be				// placed at different locations in a future version of GCC.				// g++.dg/abi/empty6.C tests this with -Wabi.				// Split into pieces for binary compatibility testing October 2002								#include "empty6.h"								extern void empty6_x (void);								int				main ()				{				  empty6_x ();				}