1 /* $NetBSD: msg_168.c,v 1.5 2021/03/25 22:53:05 rillig Exp $ */ 2 # 3 "msg_168.c" 3 4 // Test for message: array subscript cannot be > %d: %ld [168] 5 6 void print_string(const char *); 7 void print_char(char); 8 9 void 10 example(void) 11 { 12 char buf[20] = {}; /* empty initializer is a GCC extension */ 13 14 print_string(buf + 19); /* inside the array */ 15 16 /* 17 * It is valid to point at the end of the array, but reading a 18 * character from there invokes undefined behavior. 19 * 20 * The pointer to the end of the array is typically used in (begin, 21 * end) tuples. These are more common in C++ than in C though. 22 */ 23 print_string(buf + 20); 24 25 print_string(buf + 21); /* undefined behavior, not detected */ 26 27 print_char(buf[19]); 28 print_char(buf[20]); /* expect: 168 */ 29 } 30 31 void 32 array_with_c99_initializer(void) 33 { 34 static const char *const to_roman[] = { 35 ['0'] = "undefined", 36 ['5'] = "V", 37 ['9'] = "IX" 38 }; 39 40 print_string(to_roman['9']); 41 print_string(to_roman[':']); /* expect: 168 */ 42 } 43