1 /* $NetBSD: msg_217.c,v 1.11 2022/06/22 19:23:18 rillig Exp $ */ 2 # 3 "msg_217.c" 3 4 // Test for message: function '%s' falls off bottom without returning value [217] 5 6 int 7 random(int n) 8 { 9 if (n < 0) 10 return -3; 11 } 12 /* expect-1: warning: function 'random' falls off bottom without returning value [217] */ 13 14 /* 15 * The pattern 'do { } while (0)' is often used in statement macros. 16 * Putting a 'return' at the end of such a macro is legitimate, the embracing 17 * 'do { } while (0)' is probably there to conform to a coding standard or 18 * to otherwise reduce confusion. 19 * 20 * Seen in external/bsd/libevent/dist/event_tagging.c, function 21 * encode_int_internal. 22 * 23 * Before tree.c 1.243 from 2021-03-21, lint wrongly reported that the 24 * 'while 0' was unreachable. This has been fixed by allowing the 'while 0' 25 * in a do-while-false loop to be unreachable. The same could be useful for a 26 * do-while-true. 27 * 28 * Before func.c 1.83 from 2021-03-21, lint wrongly reported that the function 29 * would fall off the bottom. 30 */ 31 int 32 do_while_return(int i) 33 { 34 do { 35 return i; 36 } while (0); 37 } 38 39 /* 40 * C99 5.1.2.2.3 "Program termination" p1 defines that as a special exception, 41 * the function 'main' does not have to return a value, reaching the bottom 42 * is equivalent to returning 0. 43 * 44 * Before func.c 1.72 from 2021-02-21, lint had wrongly warned about this. 45 */ 46 int 47 main(void) 48 { 49 } 50 51 int 52 reachable_continue_leads_to_endless_loop(void) 53 { 54 for (;;) { 55 if (1) 56 continue; 57 break; 58 } 59 } 60 61 int 62 unreachable_continue_falls_through(void) 63 { 64 for (;;) { 65 if (0) 66 /* expect+1: warning: statement not reached [193] */ 67 continue; 68 break; 69 } 70 } 71 /* expect-1: warning: function 'unreachable_continue_falls_through' falls off bottom without returning value [217] */ 72