void test(void (*fun)(void)); void test(void (*fun)(void)) { typedef typeof(__builtin_trap) t; // OK void (*f)(void); int i; f = __builtin_trap; f = &__builtin_trap; f = *__builtin_trap; // OK for GCC f = __builtin_trap + 0; f = __builtin_trap + 1; f = __builtin_trap - 1; // (void) __builtin_trap; f = (void*) __builtin_trap; f = (unsigned long) __builtin_trap; i = !__builtin_trap; i = (__builtin_trap > fun); i = (__builtin_trap == fun); i = (fun < __builtin_trap); i = (fun == __builtin_trap); __builtin_trap - fun; fun - __builtin_trap; } /* * check-name: builtin arithmetic * check-command: sparse -Wno-decl $file * check-known-to-fail * * check-error-start builtin-arith.c:10:xx: error: ... builtin-arith.c:11:xx: error: ... builtin-arith.c:13:xx: error: arithmetics on pointers to functions builtin-arith.c:14:xx: error: arithmetics on pointers to functions builtin-arith.c:15:xx: error: arithmetics on pointers to functions builtin-arith.c:18:xx: error: ... builtin-arith.c:19:xx: error: ... builtin-arith.c:21:xx: error: ... builtin-arith.c:22:xx: error: ... builtin-arith.c:23:xx: error: ... builtin-arith.c:24:xx: error: ... builtin-arith.c:25:xx: error: ... builtin-arith.c:27:24: error: subtraction of functions? Share your drugs builtin-arith.c:28:13: error: subtraction of functions? Share your drugs * check-error-end */