Warning fixes & impossible-failure improvements

- Silence a couple warnings for less-common builds.
- Use a better impossible-failure idiom than assert(0).

clientname.c

@@ -139,7 +139,7 @@ char *client_name(const char *ipaddr)
 		break;
 #endif
 	default:
-		assert(0);
+		NOISY_DEATH("Unknown ai_family value");
 	}
 	freeaddrinfo(answer);
 

flist.c

@@ -680,7 +680,9 @@ static struct file_struct *recv_file_entry(int f, struct file_list *flist, int x
 	int extra_len = file_extra_cnt * EXTRA_LEN;
 	int first_hlink_ndx = -1;
 	int64 file_length;
+#ifdef CAN_SET_NSEC
 	uint32 modtime_nsec;
+#endif
 	const char *basename;
 	struct file_struct *file;
 	alloc_pool_t *pool;
@@ -767,7 +769,9 @@ static struct file_struct *recv_file_entry(int f, struct file_list *flist, int x
 			struct file_struct *first = flist->files[first_hlink_ndx - flist->ndx_start];
 			file_length = F_LENGTH(first);
 			modtime = first->modtime;
+#ifdef CAN_SET_NSEC
 			modtime_nsec = F_MOD_NSEC_or_0(first);
+#endif
 			mode = first->mode;
 			if (atimes_ndx && !S_ISDIR(mode))
 				atime = F_ATIME(first);
@@ -803,10 +807,12 @@ static struct file_struct *recv_file_entry(int f, struct file_list *flist, int x
 		} else
 			modtime = read_int(f);
 	}
+#ifdef CAN_SET_NSEC
 	if (xflags & XMIT_MOD_NSEC)
 		modtime_nsec = read_varint(f);
 	else
 		modtime_nsec = 0;
+#endif
 	if (!(xflags & XMIT_SAME_MODE))
 		mode = from_wire_mode(read_int(f));
 	if (atimes_ndx && !S_ISDIR(mode) && !(xflags & XMIT_SAME_ATIME)) {

lib/sysacls.c

@@ -798,7 +798,7 @@ int sys_acl_free_acl(SMB_ACL_T acl_d)
 /* calls if it isn't there.                            */
 
 #ifdef __TANDEM
-inline do_acl(const char *path_p, int cmd, int nentries, struct acl *aclbufp)
+inline int do_acl(const char *path_p, int cmd, int nentries, struct acl *aclbufp)
 {
 	return acl((char*)path_p, cmd, nentries, aclbufp);
 }

main.c

@@ -1555,11 +1555,13 @@ static void sigusr2_handler(UNUSED(int val))
 	_exit(0);
 }
 
+#if defined SIGINFO || defined SIGVTALRM
 static void siginfo_handler(UNUSED(int val))
 {
 	if (!am_server && !INFO_GTE(PROGRESS, 1))
 		want_progress_now = True;
 }
+#endif
 
 void remember_children(UNUSED(int val))
 {

options.c

@@ -1358,7 +1358,7 @@ char *alt_dest_opt(int type)
 	case LINK_DEST:
 		return "--link-dest";
 	default:
-		assert(0);
+		NOISY_DEATH("Unknown alt_dest_opt type");
 	}
 }
 

rsync.h

@@ -1435,3 +1435,8 @@ char *getpass(const char *prompt);
 #ifdef MAINTAINER_MODE
 const char *get_panic_action(void);
 #endif
+
+#define NOISY_DEATH(msg) do { \
+    fprintf(stderr, "%s in %s at line %d\n", msg, __FILE__, __LINE__); \
+    exit_cleanup(RERR_UNSUPPORTED); \
+} while (0)

token.c

@@ -87,7 +87,7 @@ void init_compression_level(void)
 		break;
 #endif
 	default: /* paranoia to prevent missing case values */
-		assert(0);
+		NOISY_DEATH("Unknown do_compression value");
 	}
 
 	if (do_compression_level == CLVL_NOT_SPECIFIED)
@@ -1049,7 +1049,7 @@ void send_token(int f, int32 token, struct map_struct *buf, OFF_T offset,
 		break;
 #endif
 	default:
-		assert(0);
+		NOISY_DEATH("Unknown do_compression value");
 	}
 }
 
@@ -1076,7 +1076,7 @@ int32 recv_token(int f, char **data)
 		return recv_compressed_token(f, data);
 #endif
 	default:
-		assert(0);
+		NOISY_DEATH("Unknown do_compression value");
 	}
 }
 
@@ -1103,6 +1103,6 @@ void see_token(char *data, int32 toklen)
 		break;
 #endif
 	default:
-		assert(0);
+		NOISY_DEATH("Unknown do_compression value");
 	}
 }