1  #include <stdint.h>
       2  
       3  #define STACK_CHK_GUARD \
       4    ({ uintptr_t x; asm ("lwz %0,-28680(2)" : "=r" (x)); x; })
       5  
       6  #define POINTER_CHK_GUARD \
       7    ({												\
       8       uintptr_t x;										\
       9       asm ("lwz %0,%1(2)"									\
      10  	  : "=r" (x)										\
      11  	  : "i" (offsetof (tcbhead_t, pointer_guard) - TLS_TCB_OFFSET - sizeof (tcbhead_t))	\
      12           );											\
      13       x;												\
      14     })