用于进行gcc测试

				// { dg-do compile { target arm*-*-symbianelf* } }				// Class data should not be exported.				// { dg-final { scan-hidden "_ZTI1A" } }				// { dg-final { scan-hidden "_ZTS1A" } }				// { dg-final { scan-hidden "_ZTV1B" } }				// { dg-final { scan-hidden "_ZTI1B" } }				// { dg-final { scan-hidden "_ZTS1B" } }								struct A {};				struct B : virtual public A {};				B b;