Use the alignment attribute to specify how objects of a specific type should be aligned.
For example, the following typedef declaration aligns all definitions of T1 on an 8-byte boundary.
typedef int T1 __attribute__ ((aligned (8))); T1 t1;
The following typedef declaration aligns all definitions of T2 on an 1-byte boundary.
typedef int T2 __attribute__ ((aligned (1))); T2 t2;