This attribute is used to force Offload™ not to duplicate the given method for SPU.

static int foo() __attribute__((no_dup));

static void func()
	offloadThread_t handle = __offload()
		int bar = foo(); // will fail at compile time, as foo is no allowed to be duplicated

It is useful to ban methods that you do not want any programmers to ever call from the SPU.