1*67e74705SXin Li int n; 2*67e74705SXin Li 3*67e74705SXin Li #ifdef B 4*67e74705SXin Li #error B is defined 5*67e74705SXin Li #endif 6*67e74705SXin Li 7*67e74705SXin Li #define A 8*67e74705SXin Li 9*67e74705SXin Li #include "c.h" 10